Article

Phylogeny and biogeography of tropical carnivorous land‐snails (Pulmonata: Streptaxoidea) with particular reference to East Africa and the Indian Ocean

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Rowson, B., Tattersfield, P. & Symondson, W. O. C. (2010). Phylogeny and biogeography of tropical carnivorous land-snails (Pulmonata: Streptaxoidea) with particular reference to East Africa and the Indian Ocean. —Zoologica Scripta, 40, 85–98. A phylogeny is presented for the speciose, near pan-tropical, carnivorous achatinoid land-snail superfamily Streptaxoidea inferred from DNA sequences (two nuclear and two mitochondrial regions) from 114 taxa from Africa, the Indian Ocean, Asia, South America and Europe. In all analyses, Streptaxidae are monophyletic, while the (two to six) previously recognised subfamilies are polyphyletic, as are several genus-level taxa including the most speciose genus Gulella, necessitating major taxonomic review. The Asian Diapheridae are sister to Streptaxidae, which forms several well-supported clades originating in a persistent basal polytomy. Divergence dating estimates, historical biogeography, and the fossil context suggest a Cretaceous origin of these families, but suggest Gondwanan vicariance predated most radiation. The basal polytomy dates to the Paleogene and may correspond to a rapid radiation in Africa. There is evidence for multiple Cenozoic dispersals followed by radiation, including at least two from Africa to South America, at least two from Africa to Asia and at least two from Africa to Madagascar, indicating Cenozoic turnover in tropical snail faunas. The endemic Seychelles and Mascarene streptaxid faunas each are composites of early Cenozoic lineages and more recent dispersals from Africa, with no direct evidence for an Asian origin as currently proposed. Peak streptaxid diversity in East Africa is explained by Neogene speciation among a large number of coexisting ancient lineages, a phenomenon most pronounced in the Eastern Arc-Coastal Forests centre of endemism. This includes Miocene diversification in Gulella, a primarily East and South-East African group which remains strikingly diverse even after unrelated ‘Gulella’ species are reclassified.

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... Understanding the biogeographic processes leading to endemic diversity is crucial both to interpretation of their evolutionary history and to the establishment of conservation strategies [9]. The majority of the extant species diversity of the Mascarene Islands has been described as the result of recent colonisations from outside the archipelago and divergence within the contemporary island system, often with immigrating lineages derived from Madagascar and Africa [10][11][12][13][14]. Yet, unexpectedly, numerous faunal elements are related to more remote regions such as Asia and the Indo-Pacific [7,[15][16][17][18]. ...
... Usually, islands are colonised from the nearest land source, and not surprisingly the Mascarene biota shows close affinities to Madagascar, which is approximately 700 km away. Terrestrial vertebrates like giant tortoises [36], Phelsuma day geckos [10] and slit-eared skinks [11] and also recently studied invertebrates such as carnivorous land-snails [12] and the golden orb spider Nephila [13] are few examples among many others [7,8,14]. We, in contrast, found no close relationships between any Malagasy (See figure on previous page.) ...
... The Mascarene archipelago is considered to be the product of an age-progressive trend of north-to-south volcanic activity, the Réunion hot spot chain, with a northward increase in age of volcanic activity [5]. It is assumed that many parts of the Réunion hot spot chain were above sea level over the last 65 million years at the time of their formation (Fig. 3) and that these islands would have been temporarily available as stepping-stones for lineages dispersing between India and Madagascar [12,17]. The next major islands that emerged prior to the rise of Mauritius were Saint Brandon (Cargados-Carajos), 385 km north-east of Mauritius, dated 31 mya, and Nazareth Bank, which is nearly contiguous with St. Brandon bank at its northern margin, dated at 35 mya [8]. ...
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Background: The study of islands as model systems plays a key role in understanding many evolutionary processes. Knowledge of the historical events leading to present-day island communities is pivotal for exploring fundamental mechanisms of speciation and adaptation. The remote Mascarene archipelago (Mauritius, Réunion, Rodrigues), considered to be the product of an age-progressive trend of north-to-south volcanic activity in the Indian Ocean, hosts a remarkably diverse, endemic and threatened concentration of flora and fauna that has traditionally been considered to be biogeographically related to Madagascar and Africa. To explore the evolutionary diversity of the Mascarene stick insects (Phasmatodea), we constructed a global phylogeny from approximately 2.4 kb of mitochondrial and nuclear sequence data of more than 120 species representing all major phasmatodean lineages. Results: Based on the obtained time-calibrated molecular tree we demonstrate that the current phasmid community of the Mascarene archipelago, which consists of members of four presumably unrelated traditional subfamilies, is the result of a single ancient dispersal event from Australasia and started radiating between 16–29 million years ago, significantly predating the age of Mauritius (8–10 million years). Conclusions: We propose that the Mascarene stick insects diversified on landmasses now eroded away, presumably to the north of Mauritius. In consequence, ancient islands have probably persisted in the Indian Ocean until the emergence of Mauritius and not only served as stepping stones for colonisation events during sea-level lowstands, but as long-lasting cradles of evolution. These ancient landmasses most likely allowed for adaptive speciation and served as significant sources of diversity that contributed to the biomes of the Mascarene archipelago and the megadiverse Madagascar.
... They have also found that many of its species cannot confidently be attributed to any subgenus (scHiLeyko 2000). A complete revision is currently impractical, but Rowson et al. (2010) recently sequenced conserved nuclear ribosomal DNA from many streptaxids, their analyses strongly supporting the view that "Gulella" is polyphyletic, with some nominal "Gulella" species even occurring in separate subfamilies. However, the pool of sequenced and unsequenced species remaining in the genus Gulella s.l. is still likely to be highly diverse. ...
... PfeiffeR 1853). The species sequenced by Rowson et al. (2010) included the South African endemic species then known as G. menkeana (e.g. by con-noLLy 1939, HeRBeRt & kiLBuRn 2004, etc.). However, we subsequently discovered that this name was consistently misapplied since connoLLy's (1939) redescription of G. menkeana, which had been based on misidentified specimens of G. albersi (L. ...
... We also attempt to investigate relationships between it and other South African and East African nominal "Gulella" species using COI mtDNA sequences. Although only a single mtDNA marker, this widely used "barcoding" region is additionally relevant since Rowson et al. (2010) found a 3-bp deletion in COI sequences from many species of Gulella s.l. that is potentially diagnostic. ...
Article
The megadiverse genus Gulella L. Pfeiffer 1856 is currently the most species-rich genus of Afrotropical land snails. Although currently polyphyletic, and treated partly as a "wastebasket taxon", the genus is likely to remain large even when this is resolved by revision. As a step towards this, the first data are provided on the anatomy of the type species, the South African G. menkeana (L. Pfeiffer 1853). Potentially diagnostic anatomical features, and the shell and radula of the genus Gulella sensu lato are discussed. COI mtDNA sequence data are provided from the neotype population of G. menkeana and from 24 other South African streptaxid species and populations. A strongly supported clade is recognised as the genus Gulella s. l. Lack of resolution still hampers the definition of the type subgenus, Gulella sensu stricto, but other subgenera within Gulella s. l. can be recognised. One South African clade of large species differs from G. menkeana in the radula. The name G. (Zulugulella) n. subgen. is introduced for this group, with G. (Z.) albersi (L. Pfeiffer 1855) (a species previously misidentified as G. menkeana) as type species. The Mauritian type species of Maurennea Schileyko 2000 and the Asian type species of Huttonella L. Pfeiffer 1856 clearly belong in Gulella s. l. on molecular and morphological grounds, and so these taxa may prove to be useful subgenera of Gulella. The Comoros taxon Pseudelma Kobelt 1904 shares the anatomical features of Gulella s. l. and may also be related. The type species of Aenigmigulella Pilsbry & Cockerell 1933 and Primigulella Pilsbry 1919 are shown to belong outside the genus Gulella s. l. and so are raised to generic rank. The analysis also shows three South African "Gulella " species in fact belong to other streptaxid genera with their centres of diversity elsewhere.
... According to our results these divergences probably date between 54.6 and 76.3 Ma (range of mean ages of stem lineages, see Table 4), most of them at or shortly after the Cretaceous-Cenozoic boundary. Early Cenozoic radiations have been inferred in other groups of stylommatophoran land snails (Wade et al., 2006;Rowson et al., 2010) and may have been triggered by the extinction of much of the terrestrial biota at the Cretaceous-Cenozoic boundary (Wade et al., 2006;Mordan and Wade, 2008;Rowson et al., 2010). ...
... According to our results these divergences probably date between 54.6 and 76.3 Ma (range of mean ages of stem lineages, see Table 4), most of them at or shortly after the Cretaceous-Cenozoic boundary. Early Cenozoic radiations have been inferred in other groups of stylommatophoran land snails (Wade et al., 2006;Rowson et al., 2010) and may have been triggered by the extinction of much of the terrestrial biota at the Cretaceous-Cenozoic boundary (Wade et al., 2006;Mordan and Wade, 2008;Rowson et al., 2010). ...
... caviomorph rodents, Poux et al., 2006;Sallam et al., 2009;platyrrhine anthropoids, Poux et al., 2006; seven lineages of gecko's, Gamble et al., 2011; the lizard genus Mabuya, Carranza and Arnold, 2003;and opisthocomiform birds, Mayr et al., 2011). Transatlantic dispersal from Africa to South America was invoked as an explanation for the presence of the Paleocene land snail genus Brasilennea, with supposedly African affinities, in the South American fossil record (Rowson et al., 2010). However, that genus is now considered part of the New World clade Urocoptoidea, based on conchological similarities . ...
Article
Clausiliidae is one of the most speciose and best-studied families of land snails. The family contributes to land snail diversity on a global scale, with three main centres of diversity: 1) western Eurasia (6 subfamilies recognized), 2) East Asia (2 subfamilies recognized) and 3) the neotropics (1 subfamily recognized i.e. Neniinae). Despite a wealth of shell-morphological and anatomical studies, a well-supported phylogeny is lacking for the family. To provide a phylogenetic framework and reevaluate morphological and biogeographic observations on the family, we compiled a dataset consisting of partial 28S rRNA, histone H3 and histone H4 nucleotide sequences covering all clausiliid subfamilies, and 23 out of 25 tribes. Our analyses (MrBayes, BEAST, PhyML) divide the family into seven highly supported clades, which were retrieved by at least two of the three markers used, and which are more or less geographically confined. Three of these clades coincide with subfamilies recognized in the current classification (Alopiinae, Garnieriinae, Laminiferinae). The monophyly of four of the remaining six hitherto accepted subfamilies is not supported, with the New World subfamily Neniinae divided across two clades. All shell-morphological characters used in classical clausiliid classification were homoplasious at the subfamily level, with the exception of the type of shell aperture formation. In contrast to previous interpretations, our results suggest that the so-called 'apostrophic' aperture found in the neotropical clausiliids, and in a European (Laminiferinae) and a SE Asian (Garnieriinae) subfamily, is in fact the plesiomorphic condition among extant Clausiliidae. The widespread and fragmented geographic distribution of this type of aperture may therefore be considered relictual. Based on an inferred Late Cretaceous or Early Cenozoic European origin of the clade of extant Clausiliidae, the ancestor(s) of the neotropical Clausiliidae must have colonized the New World after the Atlantic Ocean had opened. A taxonomic revision is proposed.
... However, as presently conceived, it includes a diverse array of species and much of the supraspecific taxonomy of genus is based on very limited evidence, with little consensus concerning the characterisation, distinctness and usage of the described subgeneric entities. Furthermore, given recent systematic work (Rowson et al. 2010) and the diversity of form exhibited in Gulella s.l., it seems probable that it is not a monophyletic radiation, instead comprising a polyphyletic assemblage of variously related lineages. ...
... Thus Connolly's concept of G. menkeana was based on misidentified specimens with no type status. Consequently, material collected subsequent to his monograph (Connolly 1939) and identified in accor dance with his description of G. menkeana is misidentified and in fact represents G. albersi (Aiken 1995;Herbert & Kilburn 2004;Rowson et al. 2010). The question that then arises is -what is the real Gulella menkeana? ...
... However, the species has been rarely mentioned in the literature, beyond mere mention of the name as the type species of Gulella. We are aware of only three instances where the species, as conceived by Connolly (1939), has been cited subsequently in print (Aiken 1995;Herbert & Kilburn 2004;Rowson et al. 2010). Conversely, the original concept of the species has not completely fallen out of use and was employed by Schileyko (2000). ...
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Gulella menkeana (Pfeiffer, 1853) is the type species of the highly diverse genus Gulella Pfeiffer, 1856 and study of its morphology and DNA is critical to our ability to define the genus sensu stricto in relation to research on the systematics of this complex genus. However, we have established that current use of the name is inconsistent with both the original description and first figure of the species. The name-bearing type is lost, and purported paratypes in the Museum für Naturkunde der Humboldt-Universität, Berlin, on which Connolly's widely-followed redescription was based, are not authentic. They have no type status and are instead specimens of Gulella albersi (Pfeiffer, 1855). Recently collected specimens conforming to Pfeiffer's description and figure of G. menkeana have been identified and a neotype is designated. This material also corresponds with the current broad interpretation of G. adamsiana (Pfeiffer, 1859), which, with its several established synonyms, we include in the synonymy of G. menkeana. There is also considerable resemblance to G. wahlbergi (Krauss, 1848), a name based on composite material and for which the lectotype is lost. We also designate a neotype for this species so as to preserve current application of the name. The possible synonymy of G. menkeana and G. wahlbergi, an older name, is of nomenclatural concern, but is not critical to the issue of defining Gulella s.s.
... The family Streptaxidae have a wide distribution in tropical and sub-tropical areas from South America to Africa and Asia (Schileyko, 2000;van Bruggen, 1972). They are particularly diverse in Africa, with $1000 described species (de Winter & Gittenberger, 1998;Rowson & Tattersfield, 2013;Rowson et al., 2011;van Bruggen, 1967). The majority of taxonomic and systematic studies of the Streptaxidae have been carried out on African taxa ( de Winter, 2008;Rowson et al. 2019;Rowson & Herbert, 2016), with few publications focused on South American or Asian groups (Barbosa et al., 2008;Clements, 2006). ...
... In contrast, the shell morphological characters in some species, e.g., the apertural teeth in Carinartemis vesperus Siriboon & Panha, 2014, are found to be variable (Siriboon et al., 2014b), demonstrating that the use of shell characters alone may be insufficient for species discrimination and classification. Most significantly, molecular phylogenetic studies of the Streptaxidae were conducted mostly on African taxa (Rowson et al., 2011;Rowson & Herbert, 2016), while the phylogenetic analyses of taxa outside of Africa are still limited and only two streptaxid species from the Indian Ocean were included in the analyses among Stylommatophora (Saadi & Wade, 2019;Wade et al., 2001Wade et al., 2006. This means the composition of streptaxid genera from other parts of the world, the relationships among those genera and species and even the position of the other streptaxid taxa within Stylommatophora still remain unclear. ...
... Molecular phylogenetic studies of the Streptaxidae to date are rather limited in scope (Sutcharit et al., 2010), with the only detailed work so far conducted on African streptaxid taxa (Rowson et al., 2011). Although within the family Streptaxidae the taxa from Southeast Asia are the second most diverse in terms of genera and species numbers (Richardson, 1988;Schileyko, 2000;Sutcharit et al., 2010), they have as yet been poorly studied. ...
Article
Southeast Asia boasts a high diversity of carnivorous terrestrial snails in the family Streptaxidae. Six genera are now recognized in this region, mainly classified by the traditional characters of shell morphology, especially the configuration of the apertural dentition and eccentric shell shape. More recently, genital characters have been used to reveal new species and genera. However, the monophyly of genera and the relationships among different genera and species have not yet been determined. In this regard, we constructed a molecular phylogeny of 89 streptaxid specimens from Thailand, Malaysia and Laos, representing 36 morphospecies in six genera using the COI and 16S rRNA mitochondrial DNA genes. Our findings revealed at least 10 clades with distinct geographic distributions. These clades were both concordant and discordant with traditional classification based on shell morphology. Both Discartemon and Perrottetia are monophyletic with strong statistical support, and congruent with the morphological classification. However, Carinartemis was retrieved as paraphyletic, and Haploptychius and Oophana were retrieved as polyphyletic. Within the genus Discartemon, the D. roebeleni species group shows differentiation between the mainland peninsula and the islands in Southern Thailand. This study is the first evolutionary hypothesis from molecular evidence helping us to assess the status of Thai streptaxid genera, revealing high species diversity amongst the Thai taxa and further complementing our understanding of the biogeographic relationships among different lineages.
... species occur in some Gulella, especially where the dentition is simple, but not in combination with the above mentioned features. A possible exception is the South African G. (Rowson et al. 2010a;Rowson & Herbert, unpublished). The shells of Dadagulella gen. ...
... Verdcourt (1953) described the radula of the Tanzanian Gulella usambarica (Craven, 1880) as consisting almost entirely of multicuspid teeth (formula 26-1-26); again, the cusps are nearly equal in size. Sequence data (Rowson et al. 2010a) show that Dadagulella gen. nov. is only distantly related to G. usambarica. ...
... The available DNA sequence data suggest that Dadagulella gen. nov. is a sister lineage to the one that contains Gulella, and that the two became separated in the Cenozoic (Rowson et al. 2010a). Further sequence data from additional species of Dadagulella gen. ...
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The genus Dadagulella gen. nov. is described to include 16 species of small, dentate, ovate-acuminate Afrotropical snails. An identification key is provided and biogeography, anatomy and systematics are discussed. The type species is the Kenyan D. radius (Preston, 1910) comb. nov., whose name has informally been used for part of the group in the past. Substantial intraspecific variation occurs in three species: D. radius itself, D. browni (van Bruggen, 1969) comb. nov. and D. minuscula (Morelet, 1877) comb. nov. (= Ennea fischeriana Morelet, 1881) (non Gulella minuscula Emberton & Pearce, 2000) . We recognise subspecies within each of these: D.radius radius (Preston, 1910) comb. nov., D. r. calva (Connolly, 1922) comb. et stat. nov., D. browni browni (van Bruggen, 1969) comb. nov., D. b. mafiensis subsp. nov., D. b. semulikiensis subsp. nov., D. minuscula minuscula (Morelet, 1877) comb. nov., D. m. mahorana subsp. nov. Six new Tanzanian species are described: D. cresswelli sp. nov., D. delta sp. nov., D. ecclesiola sp. nov., D. frontierarum sp. nov., D. minareta sp. nov., and D. pembensis sp. nov. The genus includes seven other previously described species: D. cuspidata (Verdcourt, 1962) comb. nov.; D. rondoensis (Verdcourt, 1994) comb. nov.; D. conoidea (Verdcourt, 1996) comb. nov.; D. selene (van Bruggen & Van Goethem, 1999) comb. nov.; D. meredithae (van Bruggen, 2000) comb. nov.; D. nictitans (Rowson & Lange, 2007) comb. nov.; and D. delgada (Muratov, 2010) comb. nov.
... Streptaxids have a wide distribution from South America to Africa and Asia (Bruggen, 1967;Schileyko, 2000;Sutcharit et al., 2010). The major radiation of streptaxids in Africa is particularly notable with approximately 1,000 described species (Bruggen, 1967;de Winter & Gittenberger, 1998;Rowson et al., 2010) and evidence from the East African fossil record that streptaxid genera, as with other extant East African stylommatophoran genera, were established by the Miocene, with the presence of species morphologically similar to extant taxa (Pickford, 1995(Pickford, , 2009. In Southeast Asia, species diversity within the Streptaxidae consists of approximately 130 nominal species in 13 genera (Bruggen, 1967(Bruggen, , 1972Richardson, 1988;Schileyko, 2000) but Asian streptaxids include deep Taxonomy & Systematics level structure and have an Asian sister group, the family Diapheridae (Sutcharit, et al., 2010). ...
... Indoartemon has been included in two molecular phylogenetic studies (Rowson et al., 2010;Sutcharit et al., 2010). Rowson et al. (2010) came to the conclusion that the Streptaxoidea were of Laurasian Mesozoic origin and Indoartemon came within a 'Streptaxines' clade with Early Cenozoic origin and a current distribution ranging from South America, Africa and Madagascar to Southeast Asia. ...
... Indoartemon has been included in two molecular phylogenetic studies (Rowson et al., 2010;Sutcharit et al., 2010). Rowson et al. (2010) came to the conclusion that the Streptaxoidea were of Laurasian Mesozoic origin and Indoartemon came within a 'Streptaxines' clade with Early Cenozoic origin and a current distribution ranging from South America, Africa and Madagascar to Southeast Asia. Thus the 'Streptaxine' clade has established distinct lineages over an extremely wide geographical range. ...
Article
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Carnivorous land snails attributed to the genera Indoartemon Forcart, 1946 and Carinartemis, new genus, are recorded from Thailand for the first time. Indoartemon eburneus (Pfeiffer, 1861), I. prestoni (Gude, 1903) and I. medius, new species, were collected from central and northeastern Thailand. These two genera are easily distinguished: Carinartemis, new genus, possesses a distinctive sharp and wide peripheral keel that does not occur in Indoartemon. We provide the first description of the internal anatomy of Indoartemon and Carinartemis, new genus, and establish the presence of several distinctive characters. The new genus has two new distinctive species, Carinartemis vesperus, new species, and Carinartemis striatus, new species, from isolated limestone hills in western Thailand.
... There are, however, conceptual issues embedded in these questions. Many species are defi ned on shell characters alone; anatomical and molecular studies frequently challenge established taxonomy (e.g., Giokas 2000, van Moorsel et al. 2000, Duda et al. 2011) even at levels higher than that of species (Rowson et al. 2011). In large scale comparisons, can we equate the 22 species of shell-defi ned species of Cochlicopa A. Férussac, 1821 within the former U.S.S.R. (listed, with doubts, by Sysoev and Schileyko 2009) with the possibly three largely selfi ng clades of the same genus delimited by Armbruster (1997) (Bank 2010). ...
... Some generic designations are extraordinarily unstable. They often refl ect radically different approaches to taxonomic practice, and recent molecular studies have overturned as convergent some characters used in their defi nition (van Moorsel et al. 2000, Rowson et al. 2011. Subgeneric divisions are even worse. ...
... Subgeneric divisions are even worse. Genus or higher group cladograms based on molecular data are far better (e.g., Rundell 2008;Jordaens et al. 2009, Rowson et al. 2011, especially for any study of differentiation over time. ...
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sees sustainable scholarly publishing as an inherently collaborative enterprise connecting authors, nonprofit publishers, academic institutions, research libraries, and research funders in the common goal of maximizing access to critical research. BioOne (www.bioone.org) is a nonprofit, online aggregation of core research in the biological, ecological, and environmental sciences. BioOne provides a sustainable online platform for over 170 journals and books published by nonprofit societies, associations, museums, institutions, and presses. Your use of this PDF, the BioOne Web site, and all posted and associated content indicates your acceptance of BioOne's Terms of Use, available at www.bioone.org/page/terms_of_use. Usage of BioOne content is strictly limited to personal, educational, and non-commercial use. Commercial inquiries or rights and permissions requests should be directed to the individual publisher as copyright holder. Abstract. Studies on the diversity of land molluscs raise a number of crucial questions that remain unanswered, or in some cases have not been asked. At the most fundamental level, we need to question the comparability of species concepts used in different studies, which infl uence our assessment of overall diversity and of regional differentiation. Current estimates of global diversity are likely to be too low. Beyond that, the assumption that all species can be represented by equivalent digits needs to be challenged: the range of size, habits and trophic levels needs to be taken into account. While higher taxonomic categories can be used as rough proxies for similar ecology, we have very little detailed information other than for shell size and shape, where the huge range suggests some radical differences within and among faunas. The range of niches occupied may differ among faunas: are we dealing with comparable taxonomic entities? Our knowledge of microhabitat requirements is severely defi cient.
... In coastal lizards Madagascar was colonized from Australasia, followed by colonization of Comoros and Mauritius from Madagascar (Rocha et al. 2006). There are, however, also cases of direct colonization of Mascarenes or Comoros from Africa, for example in birds (Warren et al. 2006), land snails (Rowson, Tattersfield, and Symondson 2011), and plants (Anthony et al. 2010). Similarly, East Africa is an important source of colonizers of the Seychelles, as seen in Archaius chameleons (Townsend et al. 2011), freshwater crabs (Daniels 2011) and land snails (Rowson, Tattersfield, and Symondson 2011). ...
... There are, however, also cases of direct colonization of Mascarenes or Comoros from Africa, for example in birds (Warren et al. 2006), land snails (Rowson, Tattersfield, and Symondson 2011), and plants (Anthony et al. 2010). Similarly, East Africa is an important source of colonizers of the Seychelles, as seen in Archaius chameleons (Townsend et al. 2011), freshwater crabs (Daniels 2011) and land snails (Rowson, Tattersfield, and Symondson 2011). ...
Article
ABSTRACT A preliminary population genetic study based on molecular markers,in Lycengraulis grossidens and Pimelodus albicans species,from “Río de la,Plata” and its “Frente Marítimo” was,carried out within FREPLATA Project. The null hypothesis assume anextensive,and ,panmictic ,population ,and ,the present ,study try to detect subpopulations or stock structure within the taxa analyzed from Río de la Plata, Frente Marítimo and its associated basins. Cytochrome ,b sequences ,(≅ 700 bp) showed,and ,important ,informative content of ,the ,genetic ,diversity and ,the population,structure. The genetic variability was ,not homogeneous ,among ,all collection sites. While both species have migratory habits, they showed structured population among,samples,belonging to distant distribution localities. The genetic estimates,of the ,population ,polymorphism ,and ,the ,phylogenetic ,analyses performed,from haplotypes provided valuables tools for fisheries management,and conservation purposes,concerning these species. INTRODUCCION Elpresente trabajo aborda de manera preliminar, la detección de poblaciones locales y "stocks" en dos,especies distribuidas en el,Río de la,Plata y su Frente Marítimo: Licengraulis,grossidens,(Clupeiformes: Engraulidae) y de Pimelodus albicans , (Siluriformes: Pimelodidae). Se ha mencionado (Scverlij et al. 1998) que ambas ,especies realizan migraciones ,en áreas ,más o menos extensas del Río de la Plata y su sistema de ríos asociados, pero se desconoce,en profundidad ,aspectos ,de la ,dinámica poblacional ,en ambos taxones. Los marcadores ,elegidos (secuencias ,de ADN mitocondrial) permiten inferir los niveles de flujo génico y de,divergencia genética entre individuos de las localidades muestreadas ,permitiendo ,definir si se ,trata de una ,única población suficientemente extensa o de,subpoblaciones diferenciadas,localmente dentro de estas dos especies que constituyen recursos,compartidos. MATERIAL Y METODOS Muestras Este trabajo incluyó 34 ejemplares ,(juveniles y adultos) ,de ,Licengraulis
... Currently, the Streptaxidae are divided into 6 subfamilies comprising some 60 genera and about a thousand nominal species (Zilch 1960, Richardson 1988, Schileyko 2000. In the recent decades, most of the taxonomic and systematic research on streptaxids has been performed on sub-Saharan African taxa, where the species diversity reaches its maximum (Rowson et al. 2010). Only a few publications focus on South American or Asian groups (Barbosa et al. 2008, references therein;Clements 2006). ...
... Only a few publications focus on South American or Asian groups (Barbosa et al. 2008, references therein;Clements 2006). Recently, the deep phylogenetic structure of the Streptaxoidea has been revealed, resulting amongst others in the recognition of a Southeast Asian lineage as a distinct family, the Diapheridae Panha and Naggs, 2010(Sutcharit et al. 2010, Rowson et al. 2010. ...
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AbstractThree new species of the streptaxid snail genus Perrottetia are described from north and northeastern Thailand, Perrottetia aquilonaria sp. n., Perrottetia dermapyrrhosa sp. n. and Perrottetia phuphamanensis sp. n. Each species is endemic to a single or a few limestone mountain ranges. The species are characterized by the morphology of their genital organs, as well as by shell characters. Perrottetia aquilonaria sp. n. has a club shaped distal penis and large penial hooks are present and penial papillae cover almost the entire penial hook portion; adjacent areas possess low reticulated folds. Perrottetia dermapyrrhosa sp. n. has a long genital atrium and the penial sheath is about two-thirds of the penis length. Penial hooks are long, scattered and sunken into deep ovate hollows; vaginal hooks are present. Perrottetia phuphamanensis sp. n. has a rounded and protruded shell periphery. The aperture is subcircular, peristome is thick and the second parietal lamella is adjacent to the first parietal lamella; a basal lamella is the smaller than in the other Thai species.
... The Streptaxoidea is divided into two sister families, Streptaxidae Gray, 1860and Diapheridae Panha & Naggs, 2010(Sutcharit et al. 2010). The superfamily is thought to have originated on the Laurasian continent during the Mesozoic era (Rowson et al. 2010). The Streptaxidae are carnivorous land snails occurring in tropical and subtropical areas from South America to Africa and Asia (Bruggen 1967, Schileyko 2000, Sutcharit et al. 2010. ...
... Most appear to be active predators feeding on other snails or other soil invertebrates, and may also be cannibalistic (Gray 1860, Blanford and Godwin-Austen 1908, Benthem Jutting 1954, Berry 1963. Streptaxids are particularly diverse in Africa, with hundreds of described species (Bruggen 1967, Winter and Gittenberger 1998, Rowson et al. 2010, Rowson and Tattersfield 2013. They are also diverse in Southeast Asia, comprising more than 130 nominal species in 15 genera (Blanford and Godwin-Austen 1908, Benthem Jutting 1954, Zilch 1960, Richardson 1988, Schileyko 2000, Siriboon et al. 2013. ...
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Twelve new species of the streptaxid snail genus Discartemon Pfeiffer, 1856 are described from southern Thailand and western Malaysia, D. afthonodontia sp. n., D. circulus sp. n., D. deprima sp. n., D. discadentus sp. n., D. discamaximus sp. n., D. expandus sp. n., D. flavacandida sp. n., D. kotanensis sp. n., and D. megalostraka sp. n. from southern Thailand, as well as D. conicus sp. n., D. epipedis sp. n. and D. triancus sp. n. from western Malaysia. All 15 previously described species are revised and commented upon based on examined material. Streptaxis paradiscus Möllendorff, 1900 is considered a junior subjective synonym of the type species D. discus (Pfeiffer, 1853). Details of the genital anatomy of twelve species, and the radula and pallial system, are provided for the first time. An identification key is provided.
... However, there were significant bivariate correlations between species richness and sampling effort and amount of leaf litter. Only amount of leaf litter was included in a 'Gulella' is polyphyletic and none of the West African endemics for which DNA sequences are available proved to be a Gulella sensu stricto (Rowson, Tattersfield & Symondson, 2010). Thus, these species have to be classified in separate genera (see also de Winter, 2008). ...
... However, we hardly know anything about the niches of individual snail species, so we cannot exclude that congeneric species are adapted to different niches. Moreover, several of the larger generic entities used here are in need of revision and are probably composed of various distantly related groups (de Winter & Gittenberger, 1998;Rowson, Tattersfield & Symondson, 2010) so that the attribute 'congeneric' may be of limited value. ...
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We investigated the land-snail fauna of rain forests on the eastern slopes of Pico Biao on Bioko Island in the Gulf of Guinea. Thirty-seven plots were studied along an altitudinal transect reaching from sea level (lowland rain forest) to an altitude of 1,830 m (mossy forest). A total of 1,755 specimens were collected and were assigned to 68 land-snail species. Eleven species were new records for Bioko. At least 15 of the recorded species are endemic to Bioko. The degree of endemism was high in mossy forest (23%) and in lowland rain forest (20%), but lower in montane forest (8%). Species richness showed a hump-shaped distribution along the altitudinal gradient with a maximum at 500 m a.s.l. Species richness peaked in forests in which there had been selective logging more than 50 years ago, indicating that some disturbance may have beneficial effects on biodiversity. Species richness was correlated with the thickness of leaf litter. The availability and quality of suitable microhabitats is more important for the occurrence of snail species than gradients of otherwise often decisive environmental parameters like temperature, which are strongly correlated with altitude. A lack of clustering of the occurrences of different snail species along the altitudinal gradient indicated a Gleasonian meta-community structure with individualistic responses of the various species to environmental parameters. No negative co-occurrence patterns that might provide evidence for interspecific competition could be detected. The frequent coexistence of morphologically similar, and presumably ecologically equivalent, congeneric species may indicate that such equivalents do not exclude each other as predicted by the neutral theory of biodiversity. However, current knowledge about individual snail species is too scanty to exclude the possibility that niches of congeneric species differ in some details.
... However, G. dautzenbergi clearly does not belong to Avakubia, lacking typical characters for the genus, such as the spiral sculpture on the apex (see Connolly 1928;Degner 1934a), and belongs to a rather different streptaxid radiation. Recent molecular work by Rowson et al. (2011) indicates that A. avakubiensis is not related to the genus Gulella and even occupies a basal position within the Streptaxidae. In the present study, Avakubia is for the first time treated as an independent genus. ...
... Traditionally postulated biogeographic barriers like the Dahomey Gap and Cross River have apparently not restricted the distribution of the genus, which might suggest a considerable age for the taxon. On molecular grounds Rowson et al. (2011) suggested Avakubia to be an ancient taxon that possibly survived the Mesozoic ⁄ Cainozoic mass extinctions, whilst the streptaxid diversity is otherwise known from the Cainozoic only. Etymology: The species is named after Adolfo Ortiz de Zárate Lopez and his son Antonio Ortiz de Zárate Rocandio, who collected and described this peculiar form without formally naming it. ...
Article
A revision of the world-wide available material of the Afrotropical streptaxid subgenus Avakubia Pilsbry, 1919, prompted the change in status to independent genus and the detection of undescribed species. In addition to the two earlier described species, A. avakubiensis (Pilsbry, 1919) and A. acuminata (Thiele, 1933), the genus Avakubia is found to embrace at least seven new species, viz., A. crystallum de Winter, sp.n. from Gabon; A. fruticicola de Winter & Vastenhout, sp. n., A. semenguei de Winter & Vastenhout, sp. n. and A. subacuminata de Winter & Vastenhout, sp. n. from Cameroon; A. ortizdezarateorum de Winter & Vastenhout, sp. n. and A. biokoensis de Winter & Vastenhout, sp. n. from Bioko I., Equatorial Guinea, and A. occidentalis de Winter, sp. n. from Ghana. Of some other potentially new Avakubia species insufficient material is available to allow a formal description. For a West African radiation with remarkably similar shells, but differing from true Avakubia in protoconch and teleoconch characters, a new genus Pseudavakubia de Winter & Vastenhout, gen. n. is erected with four new species, viz., P. atewaensis de Winter, sp. n., P. majus de Winter & Vastenhout, sp. n. (type species), P. ghanaensis de Winter, sp. n., and P. liberiana de Winter, sp. n. Avakubia avakubiensis has been reported in the literature from Uganda to Liberia, a range of 4750 km. Study of this material restricts the range of this species to the eastern Democratic Republic of the Congo and Uganda, the remaining records were found to refer to five other species of Avakubia or Pseudavakubia described in this paper, each with a much more restricted range. The genital anatomy of both Avakubia and Pseudavakubia is found to deviate from most other members of the family Streptaxidae in the absence of chitinous spines in the penis. Both genera are ovoviviparous. In the penis of a specimen of A. acuminata a spermatophore-like structure was found. Some aspects of the ecology of these rainforest-dwelling snails are described. An identification key to the species of Avakubia and Pseudavakubia is provided.
... Gulella infans (Craven, 1880), which differs in the presence of a labral tooth. In addition, the Eocene occurrence fits well with the molecular phylogeny of the Streptaxidae published by Rowson et al. (2011), who discussed a major radiation of the group during the Palaeocene and Eocene including the appearance of Gulella sensu lato. Interestingly, Van Bruggen and Van Goethem (1997) considered an aperture type with no or simple dentition a plesiomorphic trait, which would also fit to the Omani species. ...
... Among these, the occurrences of Lanistes, Pila and Gulella s.l. are rather reliable and are most probably not just a result of convergences. Especially Gulella fits also to expected radiations Terrestrial and lacustrine gastropods from the Priabonian (upper Eocene) of the Sultanate of… based on molecular data (Rowson et al. 2011). In addition, the Pomatiidae, herein united in the new genus Omanitopsis, might be closely related to extant taxa such as Cyclotopsis, as discussed also by Neubert and Van Damme (2012). ...
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Terrestrial and aquatic gastropods from the upper Eocene (Priabonian) Zalumah Formation in the Salalah region of the Sultanate of Oman are described. The assemblages reflect the composition of the continental mollusc fauna of the Palaeogene of Arabia, which, at that time, formed parts of the southeastern Tethys coast. Several similarities with European faunas are observed at the family level, but are rarer at the genus level. These similarities point to an Eocene (Priabonian) rather than to a Rupelian age, although the latter correlation cannot be entirely excluded. At the species level, the Omani assemblages lack any relations to coeval faunas. This suggests the possible presence of a distinct biogeographic province during the Palaeogene or may simply reflect the extremely sparse non-marine fossil record of the Eocene in the Tethys region. The occurrence of the genera Lanistes, Pila, and Gulella along with some pomatiids, probably related to extant genera, suggests that the modern African–Arabian continental faunas can be partly traced back to Eocene times and reflect very old autochthonous developments. In contrast, the diverse Vidaliellidae went extinct, and the morphologically comparable Neogene Achatinidae may have occupied the equivalent niches in extant environments. Carnevalea Harzhauser and Neubauer nov. gen., Arabiella Kadolsky, Harzhauser and Neubauer nov. gen., Pyrgulella Harzhauser, Kadolsky and Neubauer nov. gen., Salalahia Kadolsky, Harzhauser and Neubauer nov. gen., Omanitopsis Harzhauser and Neubauer nov. gen., Arabicolaria Harzhauser and Neubauer nov. gen., Pacaudiella Harzhauser and Neubauer nov. gen., Goniodomulus Harzhauser and Neubauer nov. gen., Eoquickia Harzhauser and Neubauer nov. gen., Omanillya H. Nordsieck nov. gen. and Omanifera H. Nordsieck nov. gen. are introduced as new genera. Pila neuberti Harzhauser and Neubauer nov. sp., Arabiella arabica Kadolsky, Harzhauser and Neubauer nov. sp., Pyrgulella parva Harzhauser, Kadolsky and Neubauer nov. sp., Salalahia thaytinitiensis Kadolsky, Harzhauser and Neubauer nov. sp., Omanitopsis vandammei Harzhauser and Neubauer nov. sp., Procyclotopsis eocenica Harzhauser and Neubauer nov. sp., Palaeocyclotus kuehschelmi Harzhauser and Neubauer nov. sp., Arabicolaria arabica Harzhauser and Neubauer nov. sp., Pacaudiella omanica Harzhauser and Neubauer nov. sp., Pacaudiella flammulata Harzhauser and Neubauer nov. sp., Goniodomulus solaniformis Harzhauser and Neubauer nov. sp., Cerastus hyznyi Harzhauser and Neubauer nov. sp., Omanillya lunellifera H. Nordsieck nov. sp., Omanillya costellata H. Nordsieck nov. sp., and Omanifera euclista H. Nordsieck nov. sp. are described as new species.
... In coastal lizards Madagascar was colonized from Australasia, followed by colonization of Comoros and Mauritius from Madagascar (Rocha et al. 2006). There are, however, also cases of direct colonization of Mascarenes or Comoros from Africa, for example in birds (Warren et al. 2006), land snails (Rowson, Tattersfield, and Symondson 2011), and plants (Anthony et al. 2010). Similarly, East Africa is an important source of colonizers of the Seychelles, as seen in Archaius chameleons (Townsend et al. 2011), freshwater crabs (Daniels 2011) and land snails (Rowson, Tattersfield, and Symondson 2011). ...
... There are, however, also cases of direct colonization of Mascarenes or Comoros from Africa, for example in birds (Warren et al. 2006), land snails (Rowson, Tattersfield, and Symondson 2011), and plants (Anthony et al. 2010). Similarly, East Africa is an important source of colonizers of the Seychelles, as seen in Archaius chameleons (Townsend et al. 2011), freshwater crabs (Daniels 2011) and land snails (Rowson, Tattersfield, and Symondson 2011). ...
... Lunged, air-breathing gastropod species belong to the informal group Pulmonata (Cuvier in Blainville 1814) and are primarily terrestrial (Bouchet and Rocroi 2005). Three major tropical snail families within the achatinoid (Stylommatophora) clade are prevalent throughout sub-Saharan Africa (Rowson et al. 2011). These include the carnivorous hunter snail family Streptaxoidea (Gray 1860), the awl snails of Subulinidae (Fischer and Crosse 1877), and the giant African land snail family, Achatinidae (Swainson 1840). ...
... Plotting the coordinates of known sites (refer again to Fig. 1) reveals another pattern: LSS bead sites cluster in the Afromontane belt along the eastern extent of the continent even though land snail species occupy a much broader range. Land snails are found from sea level to over 3,000 m in elevation and can live in a wide variety of biomes from coastal shores to savannah grassland to rainforest and mountainous range (Boxnick et al. 2015;Chukwuka et al. 2014;Rowson et al. 2011). If LSS raw material was more widely available, why were LSS beads seemingly restricted geographically? ...
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Shell beads are well established in the archaeological record of sub-Saharan Africa and appear as early as 75,000 BP; however, most research has focused on ostrich eggshell (OES) and various marine mollusc species. Beads made from various land snails shells (LSS), frequently described as Achatina, also appear to be widespread. Yet tracking their appearance and distribution is difficult because LSS beads are often intentionally or unintentionally lumped with OES beads, there are no directly dated examples, and bead reporting in general is highly variable in the archaeological literature. Nevertheless, Achatina and other potential cases of LSS beads are present at over 80 archaeological sites in at least eight countries, spanning the early Holocene to recent past. Here, we collate published cases and report on several more. We also present a new case from Magubike Rockshelter in southern Tanzania with the first directly dated LSS beads, which we use to illustrate methods for identifying LSS as a raw material. Despite the long history of OES bead production on the continent and the abun- dance of land snails available throughout the Pleistocene, LSS beads appear only in the late Holocene and are almost exclusively found in Iron Age contexts. We consider possible explanations for the late adoption of land snails as a raw material for beadmaking within the larger context of environmental, economic, and social processes in Holocene Africa. By highlighting the existence of these artifacts, we hope to facilitate more in-depth research on the timing, production, and distribution of LSS beads in African prehistory.
... The former group ranges through tropical Asia, Africa and South America. In contrast, the Gibbinae (at least the group probably containing Gibbus Montfort, 1810, see Rowson et al., 2010 andPáll-Gergely et al., 2015) are mostly distributed in the Seychelles and the Mascarene islands, while the extinct type genus Gibbus is known form Mauritius. An Indoartemon Forcart, 1946 species from Sri Lanka clustered together with the South American Streptartemon Kobelt, 1905, andStreptaxis Gray, 1837 in the phylogenetic tree of Rowson et al. (2010). ...
... In contrast, the Gibbinae (at least the group probably containing Gibbus Montfort, 1810, see Rowson et al., 2010 andPáll-Gergely et al., 2015) are mostly distributed in the Seychelles and the Mascarene islands, while the extinct type genus Gibbus is known form Mauritius. An Indoartemon Forcart, 1946 species from Sri Lanka clustered together with the South American Streptartemon Kobelt, 1905, andStreptaxis Gray, 1837 in the phylogenetic tree of Rowson et al. (2010). Indoartemon ranges to SE Asia, and several genera of similar conchological and anatomical traits inhabit that area. ...
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Nagyelma n. gen. is erected for the northern Vietnamese Ennea aliena Bavay and Dautzenberg, 1912. The most closely related genus is probably Elma H. Adams, 1866, which also has a high-spired shell but differs from the new genus in the absence of a parietal tooth, the pointed-ovoid shell shape, and the penial sheath, which covers only half of the penis.
... The members of family Streptaxidae Gray, 1860 are known as carnivorous land snails and are characterized by an eccentric to cylindrical shell with complex apertural dentition, genitalia with hook-like structures, and living animals usually having bright yellow to red or greenish bodies (Blanford and Godwin-Austen 1908;van Benthem Jutting 1954;Berry 1963;Schileyko 2000;Verdcourt 2000;Rowson et al. 2009;Siriboon et al. 2013Siriboon et al. , 2014a. This group is distributed worldwide across the tropical and subtropical areas of South America, Africa, and Asia (van Bruggen 1967;Schileyko 2000;Sutcharit et al. 2010;Rowson et al. 2010). As in many predator-prey relationships, most streptaxid taxa are abundant in limestone microhabitats where their preferred food items are also abundant (Siriboon et al. 2013(Siriboon et al. , 2014aInkhavilay et al. 2016). ...
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The carnivorous terrestrial snail family Streptaxidae, recognized by having a regular to eccentric shell with complex apertural dentition, remains little-known and largely unexplored in Myanmar. This article presents historically recorded species and provides new data on this family. A total of eighteen species in five genera, namely Carinartemis , Discartemon , Haploptychius , Oophana , and Perrottetia from the southeastern and eastern parts of Myanmar, is examined herein. Among these, Haploptychius is the most diverse with eight species, while the remaining genera are comprised of fewer than five species each. Streptaxis birmanica and Streptaxis blanfordianus are herein synonymized with Haploptychius blanfordi , while Streptaxis hanleyanus is synonymized with Carinartemis sankeyi . Furthermore, the first genitalia and radula descriptions for three previously known species, D. tonywhitteni , C. exacutus , and C. sankeyi , are provided. Using comparative morphological and anatomical approaches, four new species are described: D. paurodeviatus sp. nov. , H. heliakosus sp. nov. , H. tenasserimicus sp. nov. , and H. karenorum sp. nov. This present study enhances the understanding of the land snail fauna in Myanmar, specifically the streptaxids, and highlights that limestone areas are important for biodiversity conservation.
... It is widely known that the Cretaceous-Tertiary boundary had a major impact on terrestrial biotas, including several terrestrial gastropod families thought to have disappeared during this period (Benton, 1993;Vajda et al., 2001;McCleod, 2004). However, this event opened a new opportunity for posterior radiation events during the early Cenozoic as is also well documented for many taxa, including different groups of Stylommatophoran land snails (Wade et al., 2006;Rowson et al., 2010;Uit de Weerd and Gittenberger, 2013). The current presence of some Hygromiidae s.l. ...
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The Helicoidea is one of the most diverse superfamilies of terrestrial land snails. In this study we present a molecular phylogeny of the western Palaearctic Helicoidea obtained by means of Neighbor Joining, Maximum Likelihood and Bayesian analysis of the mitochondrial 16S rRNA gene fragment and the nuclear rRNA gene cluster including the 3'end of the 5.8S gene, the complete ITS2 region and 5'end of the large subunit 28S. Most of the morphologically-defined families were confirmed. We propose a revised phylogenetic classification so that families, subfamilies and tribes are monophyletic. The family Hygromiidae sensu Hausdorf and Bouchet (2005) is divided into three clades which are here given familial rank: Canariellidae and Geomitridae, which are recognized for the first time at familial rank, and Hygromiidae s.str. (including Ciliella and Trochulus) that is here restricted. The subfamilies Ciliellinae, Geomitrinae, Hygromiinae, Monachainae and Trochulinae recognized in current classifications were not recovered as monophyletic groups. The familily Cochlicellidae is here given tribe rank (Cochlicellini) belonging to the Geomitridae. We describe a new tribe, Plentuisini. Three subfamilies are recognized within Helicidae: Ariantinae, Helicinae (including Theba) and Murellinae. New classification indicates that free right ommatophore retractor muscle arose only once within Geomitridae. The anatomy of the auxiliary copulatory organs of the reproductive system of families, subfamilies and tribes is highlighted. We estimate the origin of the Helicoidea at the end of the Early Cretaceous and its families as Late-Cretaceous to Paleogene. Western Palaearctic Helicoidea belongs to two different lineages that diverged around 86 Ma ago, both starting their diversification at the end of the Cretaceous (around 73-76 Ma). Radiation of some western Helicoidean families started during the Eocene. Copyright © 2014. Published by Elsevier Inc.
... A high species diversity and high degree of endemism in northern Borneo are well known for many plant and animal taxa, particularly for the central mountain ranges, that is the Crocker Range, Mount Kinabalu and the Trusmadi Range (Liew, Schilthuizen & Vermeulen, 2009;Beaman, 2005). Land snail studies in other regions suggest that vicariance events that persist long enough play crucial roles in driving radiation (Douris et al., 1998;Parmakelis et al., 2005;Fiorentino et al., 2010;Pfenninger et al., 2010;Rowson, Tattersfield & Symondson, 2011), with other factors such as dispersal events and niche differentiation causing further modification (Douris et al., 1998;Schilthuizen et al., 2004;Hausdorf & Hennig, 2004Holland & Cowie, 2009;Ketmaier et al., 2010;Kokshoorn et al., 2010). Previously, the phylogeny of Everettia species was estimated without other congener species from outside of Sabah (Liew, Schilthuizen & Vermeulen, 2009). ...
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Borneo has gone through dramatic changes in geology and topography from the early Eocene until the early Pliocene and experienced climatic cycling during the Pleistocene. However, how these changes have shaped the present-day patterns of high diversity and complex distribution are still poorly understood. In this study, we use integrative approaches by estimating phylogenetic relationships, divergence time, and current and past niche suitability for the Bornean endemic land snail genus Everettia to provide additional insight into the evolutionary history of this genus in northern Borneo in the light of the geological vicariance events and climatic fluctuations in the Pleistocene. Our results show that northern Borneo Everettia species belong to two deeply divergent lineages: one contains the species that inhabit high elevation at the central mountain range, while the other contains lowland species. Species diversification in these lineages has taken place before the Pliocene. Climate changes during the Pleistocene did not play a significant role in species diversification but could have shaped contemporary species distribution patterns. Our results also show that the species-rich highland habitats have acted as interglacial refugia for highland species. This study of a relatively sedentary invertebrate supports and enhances the growing understanding of the evolutionary history of Borneo. Species diversification in Everettia is caused by geological vicariance events between the early Miocene and the Pliocene, and the distribution patterns were subsequently determined by climatic fluctuations in the Pleistocene.
... For instance, Orthalicoidea is deemed to have originated in South America, with subsequent radiations to Central America and Australasia (Breure & Romero 2012) and possibly southern Europe and northern Africa (Hammouda et al. 2017). The orthalicoid families Bulimulidae and Odontostomidae are known from the late Cretaceous of Uruguay (Cabrera et al. 2018) and were already very diverse in Rio de Janeiro during the Paleocene (Salvador & Simone 2013) On the other hand, other common and conspicuous families in Brazil, such as the Streptaxidae, have originated elsewhere (in this case Africa), radiating to South America afterward (Rowson et al. 2010). Finally, even though a Holarctic origin has been settled on for the Helicoidea, the relationships between its South American representatives (which might include Sagdoidea) are still in flux, even after much study (e.g., Wade et al. 2007;Razkin et al. 2015). ...
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Brazil is a megadiverse country for many (if not most) animal taxa, harboring a significant portion of Earth's biodiversity. Still, the Brazilian land snail fauna is not that diverse at first sight, comprising around 700 native species. Most of these species were described by European and North American naturalists based on material obtained during 19 th-century expeditions. Early 20 th century malacologists, like Philadelphia-based Henry A. Pilsbry (1862-1957), also made remarkable contributions to the study of land snails in the country. From that point onwards, however, there was relatively little interest in Brazilian land snails until very recently. The last decade sparked a renewed enthusiasm in this branch of malacology, and over 50 new Brazilian species were revealed. An astounding portion of the known species (circa 45%) presently belongs to the superfamily Orthalicoidea, a group of mostly tree snails with typically large and colorful shells. It has thus been argued that the missing majority would be comprised of inconspicuous microgastropods that live in the undergrowth. In fact, several of the species discovered in the last decade belong to these "low-profile" groups and many come from scarcely studied regions or environments, such as caverns and islands. These places still undoubtedly hide many surprises for malacologists and there is still a long way to go until we have a good understanding of the terrestrial gastropod fauna in Brazil. The science behind this venture, however, is still underfunded and moving at a snail's pace. This is especially unsettling, as land snails are deemed one of the animal groups most vulnerable to extinction, and the overly-exploited natural environments in Brazil might not last long, especially considering the country's recent environmentally harmful policies.
... Studies which have been undertaken consist of species descriptions across a small range of taxa (Bruggen 1965(Bruggen , 1966(Bruggen , 2006Herbert 2002Herbert , 2006Herbert , 2016Bursey & Herbert 2004;Cole & Herbert 2009), a few revisions (Herbert 2007;Herbert & Moussalli 2010, 2016 and a limited number of other treatments (Sirgel 1985;Herbert 1997Herbert , 2006Herbert , 2017Herbert & Kilburn 2004). In total, only a handful of molecular studies have been undertaken on African land snails (Herbert & Mitchell 2009;Rowson & Herbert 2016;Moussalli et al. 2009;Cole et al. 2019) and very few global studies have included African taxa (Rowson et al. 2010a;Fontanilla et al. 2017;Harl et al. 2017). ...
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Chondrocyclus Ancey, 1898 is a genus of nine species of African operculate land snails restricted to indigenous forest and mesic thicket. Worn specimens (i.e., without a periostracum or operculum), on which some species descriptions and records were based, appear to be indistinguishable morphologically. A comprehensive revision of Chondrocyclus s.l. is provided here based on comparative morphological examinations of the shell, protoconch, periostracum, operculum, radula and penis, and on mitochondrial genes cytochrome c oxidase subunit I and 16S rRNA. Two genus-level lineages are recognised, Chondrocyclus s.s. and Afrocyclus gen. nov. Revised species descriptions are given for seven species. Two species, C. meredithae Bruggen, 1983 and C. chirindae Bruggen, 1986 both from north of South Africa, are removed from Chondrocyclus. Twelve new species are described: C. herberti sp. nov., C. silvicolus sp. nov., C. amathole sp. nov., C. pondoensis sp. nov., C. devilliersi sp. nov., C. pulcherrimus sp. nov., C. cooperae sp. nov., C. langebergensis sp. nov., C. kevincolei sp. nov., A. oxygala gen. et sp. nov., A. potteri gen. et sp. nov. and A. bhaca gen. et sp. nov. This is the first detailed systematic revision of an Afrotropical cyclophorid group to include morphological and molecular data. This study complements research on other taxa of low-vagility forest-dwelling habitat specialists by providing comparative distribution data for an independent, widespread group. Such evidence is urgently needed for conservation of South Africa’s threatened forest biome.
... The Streptaxoidea currently comprises two families, the worldwide Streptaxidae Gray, 1860 and the Southeast Asian endemic Diapheridae Panha and Naggs, 2010(Richardson 1988, Schileyko 2000, Rowson et al. 2010a, Sutcharit et al. 2010. The Streptaxidae Gray, 1860 are active predators with an eccentric to cylindrical shell, usually with apertural dentition, and a yellowish to orange soft body (Zilch 1960, Schileyko 2000, Rowson et al. 2010b, Siriboon et al 2013, 2014a. ...
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The family Streptaxidae in Laos is revised. Twelve species are known, mainly from limestone areas, in the genera Discartemon Pfeiffer, 1856, Perrottetia Kobelt, 1905, Haploptychius Möllendorff, 1906, and Indoartemon Forcart, 1946. Three new species, P. unidentata sp. n. and P. megadentata sp. n. from northern and central Laos, and I. diodonta sp. n. from central Laos, are described. All eight species of these three genera previously recorded from Laos are revised and discussed based on examined material from Laos, Cambodia, Vietnam and Thailand. Type material was examined and lectotypes are designated. Details of genital anatomy and radulae are provided, including the first detailed genitalia and radula descriptions from Haploptychius. Two novelties in Streptaxidae, a vaginal caecum, and the occurrence of aphallic individuals, are reported from H. pellucens (Pfeiffer, 1863).
... As far as we are aware, this is the first molecular systematic study of an Afrotropical cyclophorid group and the first African study for the Cyclophoroidea (the caenogastropod superfamily to which the Cyclophoridae belongs, sensu Bouchet et al., 2017). To date, only a handful of molecular systematic studies have been undertaken on African land snails (Herbert and Mitchell, 2009;Moussalli and Herbert, 2016;Moussalli et al., 2009;Rowson and Herbert, 2016) and a few global studies have included African taxa (Fontanilla et al., 2017;Harl et al., 2017;Rowson et al., 2010a). A few molecular phylogenetic studies of Australasian cyclophoroidean taxa have been done (Lee et al., 2008a,b;Liew et al., 2014;Marshall and Barker, 2007;Nantarat et al., 2014b;Pall-Gergely et al., 2015;Phung et al., 2017;Rundell, 2008;Sutcharit et al., 2014;von Oheimb et al., 2018;Webster et al., 2012). ...
Article
The genus ChondrocyclusAncey, 1898 contains the majority of southern African members of the Cyclophoridae, a large family of operculate land snails. We present the first molecular phylogeny of the genus based on two mitochondrial genes (16S and CO1) and complement this with an appraisal of morphological characters relating to the shell and soft parts. Worn shells on which some descriptions and records of different species were based appear to be indistinguishable morphologically, creating taxonomic confusion. We show that Chondrocyclus s. l. underwent two major radiations, one Afromontane and the other largely coastal. Accordingly, we recommend a revision recognising two genera. Chondrocyclus s. s. contains four monophyletic lineages, each characterized by a combination of morphological features. The Afromontane group is shown to be a species complex; relationships within this complex could not be resolved due to insufficient DNA sequence data. The molecular data confirms the monophyly of seven currently recognised species and provides evidence for at least twelve undescribed species; the morphological data are broadly consistent with this finding. The morphological data suggest that the two species from countries to the north of South Africa should be removed from the genus, and that Chondrocyclus sensu lato is endemic to South Africa. The historical biogeography of this group of microhabitat specialists with poor dispersal abilities contributes an additional, phylogenetically independent taxon to our understanding of the processes generating biodiversity in southern Africa, a natural laboratory for palaeobiogeography. All taxa are narrow-range endemics, underlining the importance of conserving South Africa's threatened forest habitats.
... Three genera of pleurodontid land snails are currently recognized in mainland South America: Isomeria alBers 1850, Labyrinthus Beck 1837, and Solaropsis Beck 1837. A fourth genus, Polygyratia gray 1847 is still included in some classifications (i.e., schileyko 2006), but more often is excluded from Pleurodontidae (Wurtz 1955;cuezzo 2003;Bouchet & rocroi 2005) and assigned to the Streptaxidae (Baker 1925), a polyphyletic group in need of revision (roWson et al. 2010). Yet another genus-level taxon, Olympus simone 2010, was recently erected to include a single, recently described species from Brazil (simone 2010). ...
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The species of Labyrinthus Beck and Isomeria Albers known from the Sierra Nevada de Santa Marta (SNSM) are reviewed and illustrated. Isomeria goettingi n. sp. is described as the seventh species of the family Pleurodontidae known from this region. The new taxon resembles species from the SNSM and from the Andean region of Colombia and Ecuador. The relationships between the two genera of “toothed“ Pleurodontidae from northern South America are discussed, but these relationships remain unclear due to scarcity of material suitable for anatomic and molecular studies. Lectotype designations are made for Labyrinthus colombiensis DaCosta 1901 and Helix dunkeri Pfeiffer 1852.
... Commonly, dispersal (in this case LDDE) is inferred as the alternative explanation of a biogeographical disjunction of a vicariance hypothesis (criSP et al. 2011). Land snails are generally thought not to be dispersed over long distances, despite a growing evidence of the contrary (GiTTenberGer et al. 2006, Greve et al. 2010hoekSTrA & SchilThuizen 2011;roWSon et al. 2011). In this group two instances of LDDE would need to be hypothesized and made testable using independent evidence; however, this is beyond the scope of the present paper and a topic for further research. ...
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Phylogenetic relationships of Orthalicoidea, a highly diverse and dominant element in the Neotropics, were studied using nuclear and mitochondrial DNA sequences (ITS2/28S, CO1, H3). Specimens of various locations from the Southern Hemisphere (South America, Africa, Australia, New Zealand, Solomon Islands) were analysed (74 taxa, representing 30 genera). Our results support previously presented hypotheses, but also give surprises in terms of unexpected topologies. Phylogenetic trees were estimated using maximum likelihood and Bayesian inference, and compared with traditional classifications. Phylogenetic estimations using three loci gave a strong support for monophyly of Orthalicoidea, as well as for some clades within this group (Bulimulidae, Bothriembryontidae, Orthalicidae, Amphibulimulidae), but not for others (Odontostomidae and Megaspiridae). In the resulting revision of the classification scheme of the Orthalicoidea, the tribe Simpulopsini is raised to family rank. One new subfamily is recognized, the Bostrycinae. The family Bulimulidae Tryon 1867 is retained under ICZN Art. 35.5, despite the senior synonymy of Peltellinae Gray 1855. Our analysis supports an origin of the Orthalicoidea in South America, with subsequent radiations into other parts of the Neotropics and the Southern Hemisphere. The hypothesis that the distribution on the southern continents may be explained by vicariance due to break-up of Gondwana is only partially supported by divergence time analysis using fossil calibrations. Ancestral area reconstruction suggests various independent dispersals out of South America into Central America and the West Indies, and possibly two independent dispersals to explain the remaining relations between groups of taxa on the southern continents. Divergence time analysis further shows that the major diversification of extant taxa within the superfamily may have started around the Cretaceous-Paleogene boundary.
... From a biogeographic point of view, it should be expected that native terrapin populations in Madagascar and the Seychelles are genetically clearly distinct. The vast majority of the non-flying native terrestrial and freshwater faunas of Madagascar and the Seychelles are deeply divergent from their most closely related East African species owing to the long independent history of those islands (Harmon et al. 2008; Yoder and Nowak 2009; Daniels 2011; Rowson et al. 2011; Crottini et al. 2012; Samonds et al. 2012). Yet, three recent molecular investigations have suggested that the Malagasy and Bour 1983 Bour , 1984 Iverson 1992) and sampling sites (coloured circles) for Pelusios castanoides and P. subniger; described subspecies for each species are indicated.Colour code of sites corresponds toFig. ...
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Using phylogenetic and haplotype network anal-yses of 2036 bp of mitochondrial DNA, we compare sam-ples of the two hinged terrapin species Pelusios castanoides and P. subniger from continental Africa, Madagascar and the Seychelles to infer their biogeography. Owing to the long independent history of Madagascar and the Seychelles, the populations from those islands should be deeply diver-gent from their African conspecifics. Seychellois popula-tions of the two species are currently recognized as Critically Endangered endemic subspecies. However, even though we found within P. subniger evidence for a cryptic species from the Democratic Republic of the Congo, all other samples assigned to this species were undifferentiated. This suggests that Mala-gasy and Seychellois populations of P. subniger were intro-duced by humans and that the Seychellois subspecies P. s. parietalis is invalid. This has implications for current conser-vation strategies for the Critically Endangered Seychellois pop-ulations and suggests that measures should rather focus on endemic species. The situation of P. castanoides could be different. Samples from Madagascar and the Seychelles are weakly, but consistently, differentiated from continental Afri-can samples, and Malagasy and Seychellois samples are reciprocally monophyletic in maximum likelihood analyses. However, due to a lack of samples from central and northern Mozambique and Tanzania, we cannot exclude that identical continental haplotypes exist there.
... The species has also been included in the Indo-Chinese streptaxid genus Sinoennea Kobelt, 1904. DNA sequence data, however, suggest that Pupa bicolor comes within Gulella (Rowson et al. 2011). 39 The record of E. plectosoma (Benson, 1836) from Pegu (=Bamo, Myanmar) (Gude 1914: 81) is probably erroneous (Páll-Gergely et al. unpublished manuscript). ...
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This is the very first checklist of the terrestrial gastropods of Nepal. It includes 138 species and six subspecies, of which 22 species are endemic and four are introduced. It highlights 34 species recorded for the first time in Nepal and provides new distribution records for another 30 species.
... However, scHileyKo's (2000) Enneinae are evidently polyphyletic, e.g. including both streptaxid and diapherid taxa (rowson et al. 2010(rowson et al. , sutcHarit et al. 2010. To be useful it should arguably be restricted to close relatives of Ennea. ...
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This paper describes the reproductive anatomy and the radula morphology of a Taiwanese species of Elma H. Adams, 1886, providing the first information on the anatomy of the genus. The species is provisionally identified as the type species of Elma, E. cf. swinhoei (H. Adams, 1866). Based on this and contrary to previous systematics, we suggest that Elma belongs to the subfamily Streptaxinae or Gibbinae, based on the presence of a well-developed penial sheath and the vas deferens which forms a loop under the penial sheath. Elma is the first high-spired, Southeast-Asian genus to be thus classified. We discuss possible relationships with other Streptaxoidea including the Elma-like genus Pseudelma Kobelt, 1904 and the highspired “Ennea” aliena Bavay et Dautzenberg, 1912.
... It is widely known that the Cretaceous-Tertiary boundary had a major impact on terrestrial biotas, including several terrestrial gastropod families thought to have disappeared during this period (Benton, 1993;Vajda et al., 2001;McCleod, 2004). However, this event opened a new opportunity for posterior radiation events during the early Cenozoic as is also well documented for many taxa, including different groups of Stylommatophoran land snails (Wade et al., 2006;Rowson et al., 2010;Uit de Weerd and Gittenberger, 2013). The current presence of some Hygromiidae s.l. ...
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The Helicoidea is one of the most diverse superfamilies of terrestrial land snails. In this study we present a molecular phylogeny of the western Palaearctic Helicoidea obtained by means of neighbor joining, maximum likelihood and Bayesian analysis of the mitochondrial 16S rRNA gene fragment and the nuclear rRNA gene cluster including the 3 0 end of the 5.8S gene, the complete ITS2 region and 5 0 end of the large subunit 28S. Most of the morphologically-defined families were confirmed. We propose a revised phylo-genetic classification so that families, subfamilies and tribes are monophyletic. The family Hygromiidae sensu Hausdorf and Bouchet (2005) is divided into three clades which are here given familial rank: Canariellidae and Geomitridae, which are recognized for the first time at familial rank, and Hygromiidae s.str. (including Ciliella and Trochulus) that is here restricted. The subfamilies Ciliellinae, Geomitrinae, Hygromiinae, Monachainae and Trochulinae recognized in current classifications were not recovered as monophyletic groups. The family Cochlicellidae is here given tribe rank (Cochlicellini) belonging to the Geomitridae. We describe a new tribe, Plentuisini. Three subfamilies are recognized within Helicidae: Ariantinae, Helicinae (including Theba) and Murellinae. New classification indicates that free right ommatophore retractor muscle arose only once within Geomitridae. The anatomy of the auxiliary copu-latory organs of the reproductive system of families, subfamilies and tribes is highlighted. We estimate the origin of the Helicoidea at the end of the Early Cretaceous and its families as Late-Cretaceous to Paleo-gene. Western Palaearctic Helicoidea belongs to two different lineages that diverged around 86 Ma ago, both starting their diversification at the end of the Cretaceous (around 73-76 Ma). Radiation of some western Helicoidean families started during the Eocene.
... Streptaxoidea Gray, 1860, a carnivorous land snail superfamily, evolved in the Early Cretaceous (Rowson et al. 2011) and consists of two families (Sutcharit et al. 2010;Bouchet et al. 2017) with more than 1000 species in 60 genera (Zilch 1960;Richardson 1988;Schileyko 2000). On the basis of traditional taxonomy, streptaxid snail genera are differentiated by shell characters and variation in the number of apertural teeth (Kobelt 1906(Kobelt in 1905(Kobelt -1906Schileyko 2000). ...
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We here describe a new species of the streptaxid snail genus Haploptychius from the northern Western Ghats of Maharashtra, which is the third member of the genus from India. Haploptychius sahyadriensis n. sp. is distinguished from the other Indian and South-East Asian Haploptychius sp. in having suboblique-heliciform shell, low spire and presence of one strong parietal lamella. The new species has unique genital anatomy in having a long penis with a penial sheath, the presence of penial appendix, penial hooks, atrium and vagina with longitudinal ridges and irregular transverse ridges respectively, but without any hooks. It bears a shiny muscle near the junction of the vagina, gametolytic duct and the free oviduct. Based on the shell morphology and genital characters, the new species is placed in the genus Haploptychius. Our study reveals that other unexplored areas in the northern Western Ghats may potentially harbour more undescribed land snail species which could be endemic.
... As far as we are aware, this is the first molecular systematic study of an Afrotropical cyclophorid group and the first African study for the Cyclophoroidea (the caenogastropod superfamily to which the Cyclophoridae belongs, sensu Bouchet et al., 2017). To date, only a handful of molecular systematic studies have been undertaken on African land snails (Herbert and Mitchell, 2009;Moussalli and Herbert, 2016;Moussalli et al., 2009;Rowson and Herbert, 2016) and a few global studies have included African taxa (Fontanilla et al., 2017;Harl et al., 2017;Rowson et al., 2010a). A few molecular phylogenetic studies of Australasian cyclophoroidean taxa have been done (Lee et al., 2008a,b;Liew et al., 2014;Marshall and Barker, 2007;Nantarat et al., 2014b;Pall-Gergely et al., 2015;Phung et al., 2017;Rundell, 2008;Sutcharit et al., 2014;von Oheimb et al., 2018;Webster et al., 2012). ...
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SYSTEMATICS OF THE FOREST SNAIL CHONDROCYCLUS USING MORPHOLOGY AND MOLECULES M.L. COLE 1,2, J.R. DANIELS 2, 3, N. BARKER 2, M. VILLET 4 & D.G. HERBERT 5 1 East London Museum, P.O. Box 11021 Southernwood, 5213. Email: marybursey@elmuseum.za.org; 2Department of Botany, Rhodes University, Grahamstown; 3Molecular Ecology Programme, SANBI, Kirstenbosch, Cape Town; 4Department of Zoology and Entomology, Rhodes University, Grahamstown; 5Department of Natural Science, KwaZulu-Natal Museum, Private Bag 9070, Pietermaritzburg, 3200. The Afromontane regions of South Africa have a diverse terrestrial snail fauna, but up-to-date systematic studies of the majority of taxa are lacking. Such studies are an opportunity to contribute to understanding evolutionary processes and to provide information for conservation. The genus Chondrocyclus occurs in leaf litter of forests throughout South Africa and currently also includes two species in Afromontane “islands” in Zimbabwe and Malawi. The nine species were described before the development of modern systematic methods, and were based mainly on the shells of relatively few specimens. Detailed comparative morphological observations from fresh Chondrocyclus material collected throughout South Africa distinguished three lineages, and revealed a number of undescribed species and potentially narrow range endemics, including a new species in the Amatola Mountains. To gain further evidence for updating species-level taxonomy and distribution patterns, a molecular phylogeny is being prepared based on mitochondrial genes 16S and CO1 and the nuclear gene ITS2. The morphological and molecular data are concordant, strengthening conclusions as to which populations warrant species status and providing evidence for phylogenetic relationships. This example demonstrates the value of using both molecular and morphological data in systematic studies. We removed the species from Zimbabwe and Malawi from Chondrocyclus on morphological grounds, but future molecular studies of their relationships to each other and to South African Chondrocyclus will provide insights into their systematics and biogeography within the Afromontane region.
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The history of the currently disjunct temperate rainforests of the Pacific Northwest of North America has shaped the evolution and diversity of endemics. This study focuses on how geological and climatic perturbations have driven speciation in the area by isolating lineages. We investigated the phylogenetic relationships and historical biogeography of the endemic jumping slugs (genus Hemphillia) using a multi-locus phylogeny. We evaluated the spatial distribution and divergence times of major lineages, generated ancestral area probabilities and inferred the biogeographical history of the genus. Our study revealed eight genetic lineages that formed three clades: one clade consisting of two Coast/Cascade lineages, and two reciprocally monophyletic clades that each contain a Coast/Cascade and two Rocky Mountains taxa. The results of the biogeographical analysis suggest that the ancestral range of the genus occupied Coast/Cascade habitats and then spread across into Northern Rocky Mountain interior habitats with subsequent fragmentations isolating coastal and inland lineages. Finally, there have been more recent speciation events among three lineage pairs that have shaped shallow structures of all clades. We add to our knowledge of the biogeographical history of the region in that we discovered diversification and speciation events that have occurred in ways more complex than previously thought.
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Aim An ant parasitoid wasp genus (Eucharitidae: Kapala) common in the New World exhibits the intriguing pattern of having one species distributed widely across tropical Africa and Madagascar. The unusual distribution prompted an investigation of the age, origins and diversification of the Afrotropical Kapala species. We evaluate a previous hypothesis that the species was anthropogenically introduced. Location Africa and Madagascar and the Neotropics. Methods Numerous forms of evidence are incorporated to explain the origin of the Afrotropical species Kapala ivorensis, including phylogenetic relationships, molecular dating estimates, inter‐ and intraspecific genetic distances, morphology and geography. A phylogenetic analysis was performed using six gene regions (18S, 28S‐D2, 28S‐D3‐D5, ITS2, COI and COII), and network and haplotype analyses were executed with subsets of the data. Two mitochondrial gene fragments were used to calculate divergence times under a strict clock model. Additionally, we tested for a correlation between genetic distance and geographical distance in K. ivorensis populations. Results Phylogenetic analysis supports one evolutionary origin of K. ivorensis from within a clade of New World relatives. Network and haplotype analyses of the species show no biogeographical structure, and additionally, there is no statistical phylogeographical signal. These results, in conjunction with the low amount of phenotypic intraspecific variation and the genetic distance to the nearest New World relative, provide sufficient evidence to maintain the Old World Kapala as one species. Estimated mitochondrial mutation rates suggest that this species is over 1 Myr old, thus predating any potential for recent human introduction. Main conclusions Multiple analytical methods indicate the Afrotropical K. ivorensis is molecularly distinct from the Neotropical sister species and originated from a single pre‐human dispersal. This is the first dated example of an insect that has colonized Africa via trans‐Atlantic dispersal from South America.
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High-spired South and Southeast Asian Streptaxoidea has been classified mostly in the Diapheridae, and partly in the Streptaxidae, and the systematic position of several of them has not been resolved yet. The examination of conchological characters and the analysis of the homologies of apertural barriers revealed that some new genera must be introduced. Parasinoennea Z.-Y. Chen & Páll-Gergely, new genus, is erected to include a few species from Vietnam and southern China. Platylennea Páll-Gergely, new genus, and Rowsonia Páll-Gergely, new genus, include species from the Western Ghats of southern India. Pupennea Páll-Gergely, new genus, is erected for Pupa planguncula Benson, 1863, which inhabits central India. All these three are probably members of the Diapheridae. We list all Diapheridae species of India and Myanmar, and describe three new species from Myanmar as follows: Diaphera polita Páll-Gergely, new species; Diaphera turbanophora Páll-Gergely & Grego, new species; Sinoennea montawana Páll-Gergely & Hunyadi, new species. Sinoennea longtanensis S. Ouyang, X.-M. Liu & X.-P. Wu, 2012 is treated as a synonym of Parasinoennea splendens (Möllendorff, 1882).
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The endemic Macaronesian Canaridiscus, provisionally placed in the Discidae genus Atlantica, are closely linked to the peculiar laurel forest habitat of these islands. Knowledge of Atlantica (Canaridiscus) is increased here with the description, for the first time, of the genital system of three more of its species. The epiphallus is apparently lacking and the penis is much longer than that known from any of the Discidae of Europe and North America; generally it is too large to be more than partly accommodated in the distal female genital tract. Keraea has been regarded as an endemic Macaronesian genus of Discidae known only from a few shells, but its Madeiran species has been identified as a Trochulus (Hygromiidae) and its type species (from Tenerife) also matches Hygromiidae, not Discidae. The origin and relationships of the Macaronesian Discidae are discussed. The simplest explanatory model is apparently that they represent the last living relicts of a more diverse fauna of Discidae that lived in Europe during the Tertiary; Atlantica (Canaridiscus) was probably isolated early on from the remaining Discidae. Recent literature reports multiple patterns of colonisation of Madeira and the Canaries that have varied between different groups of plants and animals. Hence, it is argued that it is unwarranted to expect to find only the single pattern of colonisation among the land snails of each of these archipelagos that was advocated by Waldén (1984).
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A large collection of mollusks was recently acquired by the Museu de Zoologia da Universidade de São Paulo (Brazil) from a commercial company. In this collection, the specimens of the family Streptaxidae from Brazil are both diverse and relatively abundant and are examined here. Herein are reported new records of 11 species, greatly extending the geographical range of the following: Rectartemon depressus (Heynemann, 1868), R. iguapensis ( Pilsbry, 1930), R. piquetensis (Pilsbry, 1930) and Streptartemon extraneus (Haas, 1955). Additionally, two new species are described: Streptaxis leirae sp. nov. and Streptaxis megahelix sp. nov.
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The streptaxid land-snails Gulella ndiwenyiensis sp. n. and G. nictitans sp. n. are described as narrow-range endemics from indigenous forest remnants in the Taita Hills, Kenya. The conservation needs of these species are likely to be similar to another Taita endemic streptaxid, Gulella taitensis Verdcourt, which has been assessed as meeting the IUCN criteria for Critically Endangered category. On shell morphology, one of the new species can be assigned to a morpho-group of others which appears to extend from eastern Kenya to eastern South Africa, while the other most closely resembles other tropical, mainly eastern, African species. We introduce data on aspects of the soft anatomy in the hope that these groupings may be tested when other taxa are investigated more thoroughly.
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The history of the study of the terrestrial molluscs of the Eastern Arc Mountains is summarised and a checklist of species known from each range is presented. Current knowledge of the fauna is patchy but each of the ranges contains endemic species and collectively they support a major proportion of the Tanzanian land-snail fauna. Recent research in the East and West Usambara, Uluguru and Nguru Mountains has revealed high levels of mollusc diversity in Bomole and Monga Forests (East Usambara Mountains) and in the limestone forest at Kimboza (Uluguru Mountains); these forests support the richest faunas reported so far from East Africa. In contrast, diversity and abundance is low in the forests of the Nguru Mountains. A similarity analysis is used to identify several clusters of sites that are related to geographical position and altitude. The significance of these findings for the conservation of East African land snails is discussed.
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Published and unpublished data are used to assess the faunal (animal) values of the Eastern Arc Mountains in terms of the numbers of endemic species, and number of species shared with the adjacent lowland Coastal Forests and with the Tanganyika-Nyasa Mountain Forest Group. Emphasis is placed on vertebrates, although some data for invertebrate groups are also provided. At least 74 vertebrate species are strictly endemic to the Eastern Arc Mountains, split as follows: birds 10 species, mammals 11 species, reptiles 23 species and amphibians 30 species. A further 40 species are near-endemics, but range slightly more widely than the strict definition of the Arc. Eastern Arc Mountain blocks that possess endemic vertebrates are the Taita Hills (two species), the East and West Usambaras (12 species), the Ngurus (one species), the Ulugurus (13 species) and eastern Udzungwas (13 species). A minimum estimate of 265 invertebrate species confined to single Eastern Arc Mountain blocks was obtained, although insufficient collection and taxonomic work means that this figure is certainly an underestimate. Detailed work in the Uluguru Mountains provided an estimation of 169 invertebrate species endemic to that mountain alone. Almost all endemic species are closed-forest specialists, although there are Eastern Arc endemic birds and butterflies confined to montane grasslands and heathlands. The most important locations for the conservation of biodiversity are the east-facing scarps directly influenced by the Indian Ocean in the largest highlands. The North and South Pare Mountains, Rubehos and Ukagurus seem genuinely poorer in endemics than other areas. The Eastern Arc Mountains possess species with both an ancient history and those of more recent evolution. Ancient affinities of the fauna are with West Africa, Madagascar and even SE Asia. An extremely long history of forest cover and environmental stability are the likely causes of these remarkable affinities.
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The use of DNA sequence data in systematic studies has brought about a revolution in our understanding of avian relationships and when combined with digitized distributional data, has facilitated new interpretations about the origins of diverse clades of the African avifauna including its diversification up through the Tertiary until the present. Here we review recent studies with special reference to Africa’s forest avifauna and specifically comment on the putative origins of ‘hotspots’ of endemism in the Eastern Arc Mountains of Tanzania and in the Cape Region of South Africa. Intriguingly, both these areas appear to have retained populations of relict taxa since the mid-tertiary thermal optimum and at the same time have been centres of recent species differentiation. L’utilisation des données portant sur la séquence ADN dans les études systématiques représente une révolution dans notre façon de comprendre les relations entre les oiseaux et, combinée avec les données numérisées sur la distribution, elle facilite de nouvelles interprétations concernant les origines de différents clades de l’avifaune africaine, y compris sa diversification tout au long du Tertiaire et jusqu’à nos jours. Nous passons ici en revue des études récentes qui se réfèrent particulièrement à l’avifaune forestière africaine, avec un commentaire spécial sur les origines putatives des hauts lieux d’endémisme dans les montagnes de l’Eastern Arc tanzanien et dans la région du Cap, en Afrique du Sud. Curieusement, ces deux endroits semblent avoir conservé des populations de taxons résiduels depuis l’optimum thermique du milieu du Tertiaire, tout en étant aussi au centre de récentes différenciations entre espèces.
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Based on collections made 1992-1996, 71 species and 8 subspecies of native Madagascan dentate Gulella Pfeiffer, 1856 (those having barriers or "teeth" in the aperture), can be recognized: G. ambalaniranae sp. nov.; G. ambanikelia sp. nov.; G. ambatovakiae sp. nov.; G. ambrensis sp. nov.; G. ambrensis andavakoerae subsp. nov.; G. ambrensis capdambri subsp. nov.; G. ambrensis orangea subsp. nov.; G. ambrensis rakotomaialai subsp. nov.; G. analamerae sp. nov.; G. andreana Fischer-Piette, Blanc and Vukadinovic, 1974; G. ankaranensis Fischer-Piette, Blanc, Blanc and Salvat, 1994; G. antongilae sp. nov.; G. beandreana sp. nov.; G. bebokae sp. nov.; G. bemarahae sp. nov,; G. bemoka sp. nov.; G. benjamini Emberton and Pearce, 2000; G. benjamini sainlelucensis subsp. nov.; G. bobaombiae sp. nov.; G. bouchardi Fischer-Piette, Blanc and Vukadinovic, 1974; G. boucheti Fischer-Piette, Blanc, Blanc and Salvat, 1994; G. capmini sp. nov.; G. celestinae sp. nov.; G. columna sp. nov.; G. constricta sp. nov.; G. fischerpiettei sp. nov.; G. fischerpietlei enigma subsp. nov.; G. fotobohitrae sp. nov.; G. gallorum Fischer-Piette, Blanc and Salvat, 1975; G. griffitlisi sp. nov.; G. hafa sp. nov.; G. hafahafa sp. nov.; G. jaominai sp. nov.; G. josephinae sp. nov.; G. kelibea sp. nov.; G. ìohabea sp. nov.; G. lubeti Fischer-Piette, Blanc, Blanc and Salvat, 1994; G. magnißca sp. nov.; G. magnorchida sp. nov.; G. mahafìnaraíra sp. nov.; G. mahagaga sp. nov.; G. mahia sp. nov.; G. manomboae sp. nov.; G. marojejyae sp. nov.; G. masoalae sp. nov.; G. miaranoniae sp. nov.; G. miaryi Fischer-Piette and Bedoucha, 1964; G. michellae sp. nov.; G. microdon (Morelet, 1860); G. microstriata sp. nov.; G. mihomehia sp. nov.; G. mitsikia sp. nov.; G. nakamaroa sp. nov.; G. namorokae sp. nov.; G. nifikelia sp. nov.; G. nosybei sp. nov.; G. orchida sp. nov.; G. pearcei sp. nov.; G. petitboucheti sp. nov.; G. pseudandreana sp. nov.; G. rakotoarisoni sp. nov.; G. ranomasina sp. nov.; G. razafyi sp. nov.; G. reeae Emberton and Pearce, 2000; G. rubinstemi Fischer-Piette, Blanc, Blanc and Salvat, 1994; G. rugosa sp. nov.; G. satisfacta Fischer-Piette, Blanc, Blanc and Salvat, 1994; G. satisfacta charlesblanci subsp. nov.; G. satisfacta vitsia subsp. nov.; G. soulaiana Fischer-Piette in Fischer-Piette, Cauquoin and Testud, 1973; G. tendronia sp. nov.; G. tsara sp. nov.; G. tsaratananae sp. nov.; G. vakinifia sp. nov.; G. vatosoa sp. nov.; G. vavakelia sp. nov.; G. vohimarae sp. nov.; and G. zanaharyi sp. nov. (G. cerea [Dunker, 1848], a Comoran species with a single unsubstantiated report from Madagascar, is dropped from the faunal list.) A dichotomous key is given to these species plus the introduced Gulella bicolor (Hutton, 1834). Conchological descriptions are given of all the species. All species are illustrated except G. bicolor, G. bouchardi, G. lubeti, G. miaryi, G. microdon, G. rubinstemi, and G. souìaiana, for which refer to the Faune de Madagascar (Fischer-Piette et al, 1994, vol. 83, pp. 1-551). Edentate Gulella of Madagascar (8 species) are treated in a separate paper.
Article
Systematic sampling of a single square km patch of rather acidic, undisturbed, fairly uniform Cameroonian rainforest during two different rainy seasons yielded 97 species of land snails, belonging to at least 12 families. Up to 45 species were collected within a single sampling site of 20 m × 20 m during a single visit, and up to 51 during two visits in different seasons. This might be the world's highest sympatric land snail diversity reported to date. Variation in species composition among the sampling sites appeared to be largely random, and not due to geographic or ecological replacement. Three (super)families make up 86% of the species, the carnivorous Streptaxidae (34%) being the most diverse. Overall snail abundance was rather low, and many species were rare. Of 64% of the species, the abundance was less than 1% of all specimens (2,654) collected. A substantial difference was observed in overall snail abundance between the two sampling periods. About 27% of the species were uniquely found in one of the two sampling periods, and many species differed more than 50% in relative abundance between these seasons. At least 27% of the species were largely or completely arboreal, and 19% were found to live both on the ground and in the vegetation; 46% of the species appear to be confined to the ground, and of 7% insufficient information was available. Major adult shell dimensions (height or diameter) range between approximately 1 and 165 mm, but the vast majority (74%) of species has adult shells smaller than 10 mm. The shell height:diameter ratio distribution is bimodal, but differs from those previously reported for other faunas by relatively many "globose" (H/D 0.8-1.2) and very tall (H/D 2.8-4.4) shells. The distribution of neither shell size nor shell shape differed between ground-dwelling and (partly) arboreal species.
Article
Edentulina Pfeiffer, 1856, contains some of the largest species of the diverse, carnivorous, land-snail family Streptaxidae and seems to be restricted to tropical Africa, Madagascar, and some other Indian-Ocean islands. Based on extensive collections made in 1992-1995, and on the 1994 Faune de Madagascar pulmonate monograph, 11 native Madagascan species of Edentulina Pfeiffer, 1856, can be recognized: E. ambongoaboae sp. nov.; E. ambra sp. nov.; E. analamerae sp. nov.; E. ankaranae sp. nov.; E. antankarana sp. nov.; E. arenicola (Morelet, 1860); E. battistinii Fischer-Piette, F. Blanc, and Salvat, 1975; E. bemarahae sp. nov.; E. bobaombiae sp. nov.; E. florensi sp. nov.; E. minor (Morelet, 1851); E. nitens (Dautzenberg, 1895); and E. rugosa sp. nov. Five species are synonymized under Edentulina minor. E. alluaudi (Dautzenberg, 1895); E. gaillardi Fischer-Piette and Bedoucha, 1964; E. intermedia (Morelet, 1851); E. montis Fischer-Piette, F. Blanc, and Salvat, 1975; and E. stumpfii Kobelt, 1904. Three species are transferred to a new genus described in a separate paper: Edentulina (?) glessi Fischer-Piette, Blanc, Blanc, and Salvat, 1994; E. (?) metula (Crosse, 1881); and E. (?) simeni Fischer-Piette, Blanc, Blanc, and Salvat, 1994. A Seychellean species, E. dussumieri (Dufo, 1840), is deleted from Madagascar's faunal list. A dichotomous key is given to the native species plus the reportedly introduced Edentulina ovoidea (Bruguiere, 1792). Conchological descriptions are given of all native species. Many promising regions of Madagascar remain uncollected. Further exploration should yield additional new species of Edentulina.
Chapter
Morphological, biochemical, and molecular data strongly suggest a common ancestry of land plants and Charophyceae sensu MATTOX & STEWART. Although it is now widely accepted that the Charophyceae are a sister group to the land plants, there is considerable disagreement over the systematics of different charophycean taxa and whether a Chara- or Coleochaete-like alga was ancestral to the land plants. Comparative analyses of complete 18S rRNA gene sequences of charophycean algae, together with sequences from bryophytes, pteridophytes and higher plants now confirm a common ancestry of charophytes and land plants. These data suggest that the Charales diverged early into a separate lineage, whereas other orders within the Charophyceae show close affinities to the bryophytes.
Article
An endemic land snail genus Mandarina of the oceanic Bonin (Ogasawara) Islands shows exceptionally rapid evolution not only of morphological and ecological traits,but of DNA sequence. A phylogenetic relationship based on mitochondrial DNA (mtDNA) sequences suggests that morphological differences equivalent to the differences between families were produced between Mandarina and its ancestor during the Pleistocene. The inferred phylogeny shows that species with similar morphologies and life habitats appeared repeatedly and independently in different lineages and islands at different times. Sequential adaptive radiations occurred in different islands of the Bonin Islands and species occupying arboreal, semiarboreal, and terrestrial habitat arose independently in each island. Because of a close relationship between shell morphology and life habitat, independent evolution of the same life habitat in different islands created species possesing the same shell morphology in different islands and Lineages. This rapid evolution produced some incongruences between phylogenetic relationship and species taxonomy. Levels of sequence divergence of mtDNA among the species of Mandarina is extremely high. The maximum level of sequence divergence at 16S and 12S ribosomal RNA sequence within Mandarina are 18.7% and 17.7%, respectively, and this suggests that evolution of mtDNA of Mandarina is extremely rapid, more than 20 times faster than the standard rate in other animals. The present examination reveals that evolution of morphological and ecological traits occurs at extremely high rates in the time of adaptive radiation, especially in fragmented environments.
Article
Full-length actin-encoding sequences were PCR-amplified from genomic DNA of six planorbid species; Biomphalaria glabrata (Say; M-line strain), B. alexandrina (Ehrenberg), B. pfeifferi (Krauss), B. tenagophila (Orbigny), B. obstructa (Morelet) and Helisoma trivolvis (Say), using primers designed from a previously reported B. glabrata cytoplasmic (β) actin cDNA. The amplified sequences contained two conserved exons (126 nt and 1005 nt, respectively), separated by an intron that varied in size between snail species (ranging from 671 to 794 nt). Sequence similarities occurred between the introns of the actin genes from B. glabrata, B. alexandrina and B. pfeifferi and between those from B. tenagophila and B. obstructa, yet considerable differences were evident between these two groups and the intron derived from H. trivolvis. Analysis of exons for sequence similarities, the presence of conserved residues (deduced amino acids), and construction of gene trees indicated that these planorbid genes encode cytoplasmic (β) actins rather than muscular (α) actins. Southern blotting and hybridisation experiments suggested that B. glabrata and H. trivolvis may have multiple (up to 5) actin genes, and it can not be ruled out that actin sequences obtained from different planorbid species were derived from paralogous genes. Interestingly however, the gene trees resolved actins derived from gastropod, cephalopod and bivalve molluscs. The sequences presented add to the growing body of information on the molecular biology of planorbid snails.
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— We studied sequence variation in 16S rDNA in 204 individuals from 37 populations of the land snail Candidula unifasciata (Poiret 1801) across the core species range in France, Switzerland, and Germany. Phylogeographic, nested clade, and coalescence analyses were used to elucidate the species evolutionary history. The study revealed the presence of two major evolutionary lineages that evolved in separate refuges in southeast France as result of previous fragmentation during the Pleistocene. Applying a recent extension of the nested clade analysis (Templeton 2001), we inferred that range expansions along river valleys in independent corridors to the north led eventually to a secondary contact zone of the major clades around the Geneva Basin. There is evidence supporting the idea that the formation of the secondary contact zone and the colonization of Germany might be postglacial events. The phylogeographic history inferred for C. unifasciata differs from general biogeographic patterns of postglacial colonization previously identified for other taxa, and it might represent a common model for species with restricted dispersal.
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The land molluscs of Zanzibar island (Unguja), Tanzania are reviewed based on a) published records and b) a quantatitive survey undertaken at Jozani Forest, Unguja in 2000. 58 species are recorded from Unguja, including 16 new records and a new species of Gulella (Pulmonata: Streptaxidae). Two E. African species and one Aldabran species are placed in synonymy. The resulting annotated checklist allows a comparison of the Unguja fauna with that of other parts of E. Africa and more oceanic Indian Ocean islands. Only three additional taxa are yet recorded from the other major Tanzanian coastal islands, Pemba and Mafia. Of the 61 species, seven (11%) are putative endemics for Unguja and/or Pemba/Mafia, 14 (23%) show coastal E. African distributions, 24 (39%) show wider E. African distributions, and 16 (26%) show very wide distributions in which anthropogenic introduction has often played a part. 11 (18%) also show affinities with the oceanic Indian Ocean islands; these are briefly discussed. Levels of endemism in Jozani and on Unguja as a whole are comparable to mainland E. African coastal forests that have been subject to similar surveys. Relative to these forests, species richness at Jozani is high (29 species) but variable and skewed towards a few abundant species. Data are provided on a further 25 species recorded from "Zanzibar" but of dubious localisation or identity, as a reference for future work in the region.
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Many hypotheses have been proposed to explain the presence of Gondwanan lineages in tropical Asia including, the out-of-India hypothesis, the Eurasian route hypothesis, long-distance transoceanic dispersal and the boreotropical hypothesis. Recent molecular studies support an out-of-India Gondwanan origin of some tropical Asian taxa. Specifically these studies suggest that ancient Gondwanan lineages survived on peninsular India in spite of dramatic climatic changes and Late Cretaceous volcanism. Under this model, Gondwanan lineages dispersed into Asia when peninsular India collided with Asian plate. These Gondwanan lineages represent the remnants of unique ancient biota that require urgent attention from conservationists if we are to preserve the overall evolutionary history of Indian biota.
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CONTENTS Ι. Introduction.................. 3 2. Acknowledgements................ 5 3. Revision of the genus Metachatina............ 6 4. Land molluscs of the Mkuzi and Ndumu Game Reserves...... 20 4a. Topography, climate and vegetation........... 21 4b. Systematic list................ 23 4c. Notes on ecology............... 53 5. Other new records for Zululand............ 53 6. The distribution of land molluscs in Zululand......... 71 7. The distribution of land molluscs in Southern Africa....... 76 7a. The country (topography, climate, vegetation)........ 77 7b. Composition of the fauna............. 82 7c. The endemic genera and their species.......... 88 7d. The temperate element.............. 100 7e. The tropical element.............. 102 7f. Distributional history.............. 104 8. Systematic list of families, genera and subgenera........ 108 9. Summary................... 109 10. References.................. 111 11. Index to genera and subgenera of molluscs.......... 115 1. INTRODUCTION The fauna and flora of Zululand, situated in South Africa to the southeast of Swaziland, are of particular interest to the biogeographer. To the north the area is connected with the East African lowlands through the
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Using the most up-to-the-date information available, we present a considerably revised plate tectonic and paleogeographic model for the Indian Ocean bordering continents, from Gondwana's Middle Jurassic break-up through to India's collision with Asia in the middle Cenozoic. The landmass framework is then used to explore the sometimes complex and occasionally counter-intuitive patterns that have been observed in the fossil and extant biological records of India, Madagascar, Africa and eastern Eurasia, as well those of the more distal continents.
Article
For Madagascan vicariance biogeography and phylogeny-based conservation, four land snail groups have been predicted as most readily informative: Acavidae, Boucardicus (Cyclophoridae), Reticulapex (Charopidae), and Streptaxidae. Acavids have been evaluated in a previous paper; this paper uses recently described taxa from three mountains in southeastern Madagascar to evaluate the other three groups, based on shell and reproductive characters. Phylogenetic analyses, using appropriate outgroups, were performed on all 17 Boucardicus (31 characters, 120 states), all nine Reticulapex (21 characters, 53 states), and all 15 streptaxids (19 characters, 68 states) known from the three mountains. The Boucardicus cladogram was marginally robust; it supported monophyly of the genus, and it implied evolutionary trends toward larger, more colour-patterned, more globose shells hatched from larger eggs; toward a dorsally and more weakly papillate penis with a large, external gland; and toward a broad-based, tightly convoluted fertilization pouch-seminal receptacle complex with an internal, muscular funnel. A convergence in high-spired shells supported the recent synonymization of Madecataulus under Boucardicus. According to the cladogram, a three-lobed apertural peristome was plesiomorphic, was lost, then reappeared convergently. Among the 12 dissected species of Boucardicus, morphology of the female reproductive system was extremely variable (11 of 14 character states autapomorphic). The Reticulapex cladogram supported monophyly of the genus but gave no robust resolution among species. Recent surveys also indicate that Reticulapex is rare to absent in northern Madagascar. The streptaxid cladogram suggested a sister-group relationship between the endemic clades Par-vedentulina and Streptostele (Makroconche), but provided no robust resolution among species within either clade or within Gulella. Anatomical material is relatively scarce for Madagascan streptaxids. Vicariance-biogeographic analysis resulted in the area cladogram (northern Vohimena mountain chain (southern Vohimena chain (southern Anosy chain))). The Vohimena chain, already known for its significantly greater diversity and endemism than the Anosy chain, thus also séems to harbour the older, more plesiomorphic species; this heightens the urgency for conservation and further survey within the Vohimena chain. Acavids (115 species known) remain the most accessible of Madagascar's major, widespread land-snail groups for island-wide phylogenetics and biogeography, mainly because of existing frozen-tissue collections, which have a limited shelf life. Boucardicus (177 species and 6 subspecies known) is clearly the second most accessible.
Article
The East Usambara Mountain forests constitute what is probably one of the richest biological communities in Africa in terms of plant and animal species numbers and endemic taxa. This review presents brief accounts of the flora and of three invertebrate and four vertebrate groups and shows the percentage endemic taxa to vary from 2% (mammals) to 95% (millipedes) as a proportion of the true forest species.Notes are given on the geology, soils, climate and present land use of the Usambaras. Biological richness is considered to be due to long periods of isolation and geological stability coupled with periods of species immigration during times of re-establishment of a continuous forest cover. The nature of the endemic elements is briefly discussed.Evidence is given to show that the forests are subject to increasing pressure from legal and illegal encroachment due to agriculture (tea, cardamon, subsistence) and forestry timber operations. Air photograph analysis shows a forest decrease of some 50% in the vicinity of Amani from 1954 to 1976.The low conservation status of most forest reserves and the lack of detailed knowledge on the distribution, status and biology of the endemic species means present conservation efforts are poor and haphazard. This review calls for greatly increased research inputs and a complete halt to all exploitation of natural forest areas until a long term conservation land use plan can be implemented.
Article
The Streptaxoidea are an ancient and species diverse group that is poorly understood. Examination of the reproductive anatomy of Diaphera showed it to be notably distinct from that of most other streptaxid genera but to exhibit similarities with the reproductive anatomy of Sinoennea (Enneinae), Careoradula (Strepaxinae), Discartemon (Strepaxinae), Augustula (Strepaxinae), and a species of Imperturbatia (Gibbinae). Our molecular phylogenetic analysis placed the two genera with high-spired shells, Sinoennea and Diaphera, in an isolated position as a sister group to the Streptaxidae sensu stricto. This basal divergence within the Streptaxoidea provides support to the proposed recognition of a new family, the Diapheridae. None of the genera possessing low-spired shells, Careoradula, Discartemon, Augustula, and Imperturbatia, were available for inclusion in the molecular analysis and we therefore provisionally restrict the Diapheridae to Diaphera and Sinoennea. However, based on their reproductive anatomy Careoradula, Discartemon, Augustula and a species of Imperturbatia may cluster with the Diapheridae when included in a molecular analysis.© 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 160, 1–16.
Article
The land snail superfamily Orthalicoidea, although generally assumed to be of Gondwanan origin, is considered by the majority of recent authors to be absent from the African continent. However, two poorly-known African genera, Aillya and Prestonella, have historically been referred to the orthalicoid family Bulimulidae s.l. Anatomical study of Aillya has subsequently shown it to be morphologically distinct from the Bulimulidae and referable to a family of its own, outside the Orthalicoidea, but Prestonella has remained an enigmatic taxon of unknown affinity. Using molecular and morphological evidence, we demonstrate conclusively that Prestonella is indeed a member of the Bulimulidae s.l. We thus confirm that this family is represented in Africa, and that it has a classical disjunct, tri-continental southern distribution. Thus, either the origin of the family must at the least predate the separation of Africa and South America in the Mid Cretaceous (under a vicariance scenario) or there must have been subsequent dispersal between the isolated Gondwanan fragments. In view of the limited dispersal ability of terrestrial snails, we consider the former more likely. Anatomically, Prestonella exhibits many character states thought to be plesiomorphic, suggesting a relationship with the subfamily Bulimulinae. Bayesian analysis of nuclear DNA sequence data places it as sister group (posterior probability = 1.0) to an Australasian clade comprising Bothriembryon and Placostylus. However, taxon sampling within the Orthalicoidea is currently inadequate to permit meaningful resolution of subfamilial affinity using molecular data. Similarly, although those orthalicoid taxa for which molecular data are available comprise a well-supported clade, the relationships of this clade to other stylommatophoran clades remain unresolved. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 96, 203–221.
Article
We have incorporated an additional 56 species of land snails and slugs in our ribosomal (r) RNA molecular phylogeny. The new taxa include representatives of several important groups. The molecular tree now includes 160 species of stylommatophoran land snails and slugs in 144 genera in 61 families. In the rDNA tree, the Stylommatophora are principally divided into an ‘achatinoid’ and a ‘non-achatinoid’ clade. Within these clades, several major land snail groups, including the Orthurethra, Elasmognatha, Limacoidea, and Helicoidea, are supported. Overall, the rDNA molecular phylogeny has remained stable following the incorporation of the additional taxa, with these additions having little impact on the major evolutionary patterns in the tree. Taxonomic coverage of the Orthurethra, Orthalicidae, Camaenidae, and Bradybaenidae is increased significantly. The camaenids and bradybaenids form a complex, and both appear to be paraphyletic. Several families of uncertain affinity, such as the Sagdidae and Thyrophorellidae, are included for the first time. The Sagdidae are shown to belong to the Helicoidea, and the Thyrophorellidae to the Achatinoidea. © 2006 The Linnean Society of London, Biological Journal of the Linnean Society, 2006, 87, 593–610.
Article
In February/March 1995 we collected land snails (including slugs) at 12 stations in eastern Tanzania. A total of 571 person-hours yielded 9174 snails assigned to 159 morpho-species. The richest two sites each (< 5mm="" greatest="" adult="" shell="" dimension)="" –="" many="" of="" which="" are="" probably="" undescribed="" species="" –="" comprise="" a="" substantial="" proportion="" of="" tanzanian="" molluscan="" diversity;="" more="" surveys="" are="" needed,="" especially="" because="" of="" human="" pressures="" on=&