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Urticalean rosids: Circumscription, rosid ancestry, and phylogenetics based on rbcL, trnL-F, and ndhF sequences

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Urticalean rosids: Circumscription, rosid ancestry, and phylogenetics based on rbcL, trnL-F, and ndhF sequences

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Abstract

To address the composition of the urticalean rosids, the relationships of the component families (maximally Cannabaceae, Cecropiaceae, Celtidaceae, Moraceae, Ulmaceae, and Urticaceae) and analyze evolution of morphological characters, we analyzed sequence variation for a large sampling of these families and various rosid outgroups using rbcL, trnL-F, and ndhF plastid regions. Urticalean rosids are derived out of a lineage including Barbeyaceae, Dirachmaceae, Elaeagnaceae, and Rhamnaceae, with Rosaceae less closely related; thus, they are imbedded within Rosales. Ulmaceae are the sister to all remaining families. Cannabaceae are derived out of a subclade of Celtidaceae; this expanded family should be called Cannabaceae. Cecropiaceae are derived within Urticaceae and are polyphyletic with Poikilospermum derived elsewhere within Urticaceae; this expanded family should be called Urticaceae. Monophyletic Moraceae are sister to this expanded Urticaceae. Support for these relationships comes from a number of morphological characters (floral sexuality, presence or absence of hypanthium, stamen type and dehiscence, pollen pore number, ovule position, and embryo alignment) and chromosome numbers. Most fruit types, in terms of ecological dispersal, are derived independently multiple times and are strongly correlated with habitat.

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... Ulmaceae was first established by Mirbel (1815) and contained only two genera, Ulmus and Celtis L. Subsequently, the circumscription of the Ulmaceae s.l. was expanded to contain 15-18 genera according to different classification systems and supported two subfamilies, Celtidoideae and Ulmoideae (Cronquist & Takhtajan, 1981;Dahlgren, 1983;Thome, 1983;Goldberg, 1986;Sherman-Broyles et al., 1997;Fu et al., 2003). Some studies suggested that Celtidoideae should be excluded from Ulmaceae based on flavonoid chemistry, karyomorphology, and morphological characters (e.g., Giannasi, 1978;Oginuma et al., 1990;Zavada & Kim, 1996), which was further supported by subsequent molecular phylogenetic analyses (Wiegrefe et al., 1998;Song et al., 2001;Sytsma et al., 2002;Zhang et al., 2011;Yang et al., 2013;Sun et al., 2016). The prevailing view is that the circumscription of the Ulmaceae s.s. ...
... In contrast, several molecular phylogenetic studies have resolved the systematic position of Chaetachme as sister to Pteroceltis Maxim. within Cannabaceae (Ueda et al., 1997;Sytsma et al., 2002;Yang et al., 2013;Sun et al., 2016). Therefore, the circumscription of Ulmaceae remains ambiguious. ...
... The intergeneric and intrageneric relationships in Ulmaceae are poorly resolved. This probably because previous taxonomic or phylogenetic studies were mainly based on morphological characters or fewer molecular loci such as rbcL, trnL-F, ndhF, and ITS, etc. (e.g., Fu, 1980;Ueda et al., 1997;Wiegrefe et al., 1998;Sytsma et al., 2002). Ueda et al. (1997) suggested that Ampelocera is sister to the remaining genera within Ulmaceae, whereas several subsequent studies suggested that Ampeolocera and Holoptelea formed a sister group to the remaining genera of Ulmaceae (Wiegrefe et al., 1998;Sytsma et al., 2002;Sun et al., 2016). ...
Article
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Ulmaceae are a woody family widespread in northern temperate forests. Despite the ecological importance of this family, its phylogeny and biogeographic history are poorly understood. In this study, we reconstruct phylogenetic relationships within the family and infer spatio‐temporal diversification patterns based on chloroplast genome (complete cpDNA) and nuclear ribosomal DNA sequences (nrDNA). The seven Ulmaceae genera comprising the family are resolved in two main clades (temperate vs. tropical) by both cpDNA and nrDNA sequences. The temperate clade includes four genera, Hemiptelea, Zelkova, Planera, and Ulmus. The relationships among Planera and other genera are controversial because of inconsistent topologies between plastid and nuclear data. The tropical clade includes three genera, ((Ampelocera, Phyllostylon), Holoptelea). Molecular dating and diversification analyses shows that Ulmaceae originated in the Early Cretaceous (ca. 110–125 Ma) with the main lineages establishing from the Late Cretaceous to the early Eocene. The diversification rate slowed during the middle to the late Paleogene (ca. 23–45 Ma), followed by a rapid diversification of the East Asian temperate group in the Neogene, congruent with a global cooling event. The ancestral state optimization analysis suggests an East Asian origin of the temperate Ulmaceae clade during the Paleocene, which is consistent with the fossil record. Both phylogenomic and fossil evidence support East Asia as a center of origin and diversification for the temperate woody lineages. This article is protected by copyright. All rights reserved.
... and Ulmaceae Mirb. (Zavada and Kim 1996;Sytsma et al. 2002;Zhang et al. 2011;Yang et al. 2013). The urticalean rosids have flowers with a single-whorled or no perianth (Friis 1993;Kubitzki 1993a,b;Rohwer 1993a;Todzia 1993;Ribeiro 2007;Ronse De Craene 2007, 2010Ronse De Craene and Brockington 2013) and a reduction in the size and number of organs per whorl (0-5) (see Eyde 1975;Fahn 1990;Endress 1994;Lersten 2004;Ronse De Craene 2010). ...
... The Cecropieae tribe, now circumscribed within Urticaceae (Sytsma et al. 2002;Datwyler and Weiblen 2004;Zerega et al. 2008;Clement and Weiblen 2009;Judd et al. 2007;Wu et al. 2013Wu et al. , 2015APG IV 2016), was previously considered as a family named Cecropiaceae C.C.Berg (Berg 1978). It may be recognized as an exclusively dioecious arboreal or hemiepiphytic group (Berg 1978), usually with adventitious roots. ...
... Also, the flower with a single whorled perianth of the Cecropieae species studied is the result of the corolla absence, a condition quite common in the families of the Urticoid clade (Bechtel 1921;Berg 1977Berg , 1989Sytsma et al. 2002). The only perianth whorl that is present is the calyx since it exhibits features considered in the literature to be sepal-like (Friis 1993;Endress 1994;Soltis et al. 2005;Ronse De Craene 2010), such as the asynchronous initiation of the primordia; rapid growth; epidermis with non-papillary cells; persistence after pollination (probably acting as an attractant for dispersing animals); robustness; and anatomical structure (thick mesophyll formed of juxtaposed parenchyma cells). ...
Article
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Small flowers with tubular calyces and connate stamens, a small number of whorls and organs per whorl are found in species of the tribe Cecropieae (Urticaceae). This study elucidates the processes that lead to such floral conditions by comparing the morphology of the developing flowers of Cecropia pachystachya, Coussapoa microcarpa and Pourouma cecropiifolia. Buds and flowers were examined under scanning electron and light microscopy. The tubular calyx originates from the activity of a peripheral annular meristem that results in a tube with two or three lobes. In the staminate floral meristem, the androecium primordium arises as a central bulge that elongates and originates two stamens with the filaments basally or totally united; the anthers can also be united. In the pistillate floral meristem, the gynoecium primordium also arises as a central bulge that elongates and originates two carpel primordia: one expands, forming a cleft and an ovule, and the other does not differentiate and remains rudimentary. Pistillate and staminate flowers result from the absence of the stamen or carpel, respectively, from inception. Petals are also absent from inception. The formation of the tubular calyx and connate stamens occurs very early in development, characterizing a congenital union. The union of anthers by the connectives in C. microcarpa is postgenital and occurs between epidermal cell walls through a weak
... This is intriguing because this type of gynoecium has been reported for Cannabaceae, Moraceae, and Ulmaceae (Eckardt 1937), families closely related to Urticaceae. Together these families compose the urticalean rosid clade (Sytsma et al. 2002;Zhang et al. 2011;Yang et al. 2013). ...
... Reports of monoclinous flowers are available for other members of Parietaria (Mamut and Tan 2014), but no study confirming the functionality of this floral type has been found. Monoclinous flowers have been described for Cannabaceae (Torres and Luca 2005) and Ulmaceae (Bechtel 1921;Todzia 1989Todzia , 1992Okamoto et al. 1992), which are families closely related to Urticaceae (Zavada and Kim 1996;Sytsma et al. 2002;Zhang et al. 2011;Yang et al. 2013). However, such an uncommon condition should be verified in the entire Urticalean clade, since gametophytes are not always fully developed. ...
... The flower with a reduced number of whorls found in Parietaria debilis is the result of the absence of a corolla in both floral morph types and of an androecium in the pistillate flowers from the beginning of floral development. The absence of a whorl from inception is a condition commonly found in Urticaceae (Bechtel 1921;Berg 1977;Sytsma 2002). ...
Article
Parietaria debilis is gynomonoecious, a rare condition in the Urticaceae family and among angiosperms. Apetalous flowers of two different morph types (monoclinous, pistillate) occur in the same inflorescence and are reduced in size and in the number of whorls and of organs per whorl. The objective of the present study was to compare the morphogenesis of monoclinous and pistillate flowers in order to understand if the monoclinous flowers produce fertile gametophytes and to determine the pathways leading to the absence of stamens and to the changes in number of whorls and organs per whorl. Flower buds and flowers (non-fertilized, fertilized) were processed for surface and anatomical studies. Pollen ultrastructure and viability was determined. Inflorescences with fertilized flowers were checked for the presence and location of fruits/viable seeds. The monoclinous flower has four sepals, four stamens and a uniovulate pseudomonomerous gynoecium. In the pistillate flower the stamens are absent or, rarely aborted. No petals are formed. The gynoecium is pseudomonomerous, originated as a central primordium that differentiates into two carpels, but only one develops and houses an ovule. Monoclinous and pistillate flowers produce viable seeds. Thus, our data confirmed that this species is indeed gynomonoecious.
... e Urticaceae Juss. (Sytsma et al. 2002, Judd et al. 2009, APG III 2009, APG IV 2016. Cannabaceae são plantas de hábito herbáceo, arbustivo ou arbóreo, com cistólitos nas folhas, ausência de laticíferos e tricomas simples com paredes celulares mineralizadas ou glandulosos. ...
... É o caso de Cannabis sativa L., a maconha, na produção de canabinol ou de Humulus lupulus L., utilizada na fabricaçāo de cerveja (Montford & Small 1999, Measham et al. 1994, Honório et al. 2006, Zanoli & Zavatti 2008, Hill et al. 2010, Small 2015. Essa proposta foi testada posteriormente por Song et al. (2001) que utilizaram análises de parcimônia do gene do cloroplasto (matK), Sytsma et al. (2002) através da análise 4 de parcimônia das regiões plastidiais (rbcL, trnL-trnF e ndhF), e Sattarian (2006) que utilizou análises Bayesiana e de parcimônia das regiões plastidiais (rbcL e trnL-trnF), e concluíram que a monofilia de Celtidaceae Endl. não se sustentava nas análises moleculares realizadas, o que corroborou a proposta de Yang et al. ( , 2017) para a circunscrição atual de Cannabaceae, onde Celtis e Trema são incluídos na família (APG IV 2016). ...
... Cannabaceae é considerada uma família irmã de Moraceae e Urticaceae (Sytsma et al. 2002, Sattarian 2006, Zhang et al. 2011. No entanto, as relações entre os gêneros de Cannabaceae ainda não estão resolvidas (Sattarian 2006, principalmente pelas lacunas de estudos moleculares para as espécies neotropicais do grupo. ...
Thesis
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Master's thesis. Celtis L. (Cannabaceae) from Brazil. Review of Celtis species from Brazil.
... The laticifers of Cannabis sativa (Furr and Mahlberg 1981;Mesquita and Dias 1984) and Humulus (Hagel et al. 2008) are currently classified as nonarticulated and unbranched. Cannabaceae belongs to the Urticalean Rosid clade that also comprises Moraceae, Ulmaceae, and Urticaceae (Sytsma et al. 2002). Differences in the distribution and morphology of laticifers have always been considered as important features for the diagnosis of the families of the Urticalean Rosid clade (Judd et al. 2009). ...
... d dictyosome, m mitochondria, n nucleus, rer rough endoplasmic reticulum, v vacuole, w wall. Scale bars: a, c 2 μm, b 1 μm study of Sytsma et al. (2002), laticifers were considered to be absent in these genera that were recently inserted into Cannabaceae. Therefore, our results corroborate the insertion of these genera into Cannabaceae together with Cannabis and Humulus in which the presence of laticifers throughout the plant has been previously described (Meeuse 1942;Furr and Mahlberg 1981;Mesquita and Dias 1984;Hagel et al. 2008). ...
Article
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Cannabaceae is a known family because of the production of cannabinoids in laticifers and glandular trichomes of Cannabis sativa. Laticifers are latex-secreting structures, which in Cannabaceae were identified only in C. sativa and Humulus lupulus. This study aimed to expand the knowledge of laticifers in Cannabaceae by checking their structural type and distribution, and the main classes of substances in the latex of Celtis pubescens, Pteroceltis tatarinowii, and Trema micrantha. Such information is also updated for C. sativa. Samples of shoot apices, stems, leaves, and flowers were processed for anatomical, histochemical, ultrastructural, and cytochemical analyses. Laticifers are articulated unbranched in all species instead of non-articulated as previously described for the family. They occur in all sampled organs. They are thick-walled, multinucleate, with a large vacuole and a peripheral cytoplasm. The cytoplasm is rich in mitochondria, endoplasmic reticulum, dictyosomes, ribosomes, and plastids containing starch grains and oil drops. Pectinase and cellulase activities were detected in the laticifer wall and vacuole, confirming its articulated origin, described by first time in the family. These enzymes promote the complete dissolution of the laticifer terminal walls. The latex contains proteins, lipids, and polysaccharides in addition to phenolics (C. sativa) and terpenes (C. pubescens, T. micrantha). The presence of laticifers with similar distribution and morphology supports the recent insertion of Celtis, Pteroceltis, and Trema in Cannabaceae. The articulated type of laticifer found in Cannabaceae, Moraceae, and Urticaceae indicates that the separation of these families by having distinct laticifer types should be reviewed.
... The well-known species of Cannabaceae, Moraceae, Urticaceae and Ulmaceae form a monophyletic group (Zavada and Kim 1996;Sytsma et al. 2002;Zhang et al. 2011;Yang et al. 2013) currently known as urticalean rosids ("Urticales" in the subclass Hamamelididae, e.g., Berg 1989) and included in the order Rosales (APG IV 2016). The families of urticalean rosids are not rich in species: Urticaceae is the richest (~1,300 species), followed by Moraceae (~1,100), Cannabaceae (~100) and Ulmaceae (~ 60) ("The Plant List" 2018). ...
... The androecium also consists of a single whorl with equal or smaller numbers of stamens than the organs of the perianth, with free, straight or inflexed filaments, and usually basifixed anthers. The gynoecium is bicarpellate, often with one of the carpels not emerged and reduced to a vascular trace (=pseudomonomerous), sometimes transformed into a pistillode in the staminate flower, and atrophied in a pistillate flower; the ovary is superior with one ovule in a basal or apical position and a stigma of diverse shapes (Bechtel 1921;Rivières 1958;Stern 1973;Berg 1977;Fukuoka 1982;Friis 1993;Omori and Terabayashi 1993;Sytsma et al. 2002;López-Almansa, Pannell, and Gil 2003). The flower is thus considered reduced in relation to the other rosids, especially Rosaceae species. ...
Chapter
Species of Cannabaceae, Moraceae, Urticaceae and Ulmaceae form the group of urticalean rosids. This group shares the presence of small, slightly showy, diclinous (unisexual), achlamydeous or monochlamydeous flowers, that have a bicarpellate pseudomonomerous gynoecium with a single functional ovule. The flower is considered to be reduced in relation to the other rosids. This study shows that development can explain such an uncommon floral construction of urticalean rosids. Our data are based on studies of at least 20 species, summarized as follows: (1) The monochlamydeous flower results from the absence of a petal whorl from the inception. The interspecific variation in the sepal number is also due to the absence of sepal primordia in the floral meristem. (2) The dicliny results from abortion of stamens and carpels, resulting in staminate flowers with a pistillode and pistillate flowers with staminodes. (3) The pseudomonomerous gynoecium results by the arising of one primordium at the center of the floral meristem that differentiates into two carpels; only one develops normally and produces an ovule while the other does not initiate any ovule, although part of its tissues composes the ovary and even the style and the stigma. (4) The association of the floral organ arrangement with wind pollination is remarkable in the staminate flower of some species. The pistillode inflates during flower development, propelling the anthers enveloped by the sepals outward from the floral center, releasing explosively agglutinated pollen. In the entomophylous species, the union of several stigmas of different flowers forming platforms (Ficus), or the supply of pollen and varied secretions to the pollinating insects (Artocarpus, Castila, Dorstenia) guarantee the formation of seeds. Concluding, floral development is conserved and supports the monophyly of the group. On the contrary, floral specializations are responses to the selection pressures exerted by the different pollinators in the group.
... and Ulmaceae Mirb. (Zavada and Kim 1996;Sytsma et al. 2002;Zhang et al. 2011;Yang et al. 2013). The urticalean rosids have flowers with a single-whorled or no perianth (Friis 1993;Kubitzki 1993a,b;Rohwer 1993a;Todzia 1993;Ribeiro 2007;Ronse De Craene 2007, 2010Ronse De Craene and Brockington 2013) and a reduction in the size and number of organs per whorl (0-5) (see Eyde 1975;Fahn 1990;Endress 1994;Lersten 2004;Ronse De Craene 2010). ...
... Also, the flower with a single whorled perianth of the Cecropieae species studied is the result of the corolla absence, a condition quite common in the families of the Urticoid clade (Bechtel 1921;Berg 1977Berg , 1989Sytsma et al. 2002). The only perianth whorl that is present is the calyx since it exhibits features considered in the literature to be sepal-like (Friis 1993;Endress 1994;Soltis et al. 2005; Ronse De Craene 2010), such as the asynchronous initiation of the primordia; rapid growth; epidermis with non-papillary cells; persistence after pollination (probably acting as an attractant for dispersing animals); robustness; and anatomical structure (thick mesophyll formed of juxtaposed parenchyma cells). ...
Article
Full-text available
Small flowers with tubular calyces and connate stamens, a small number of whorls and organs per whorl are found in species of the tribe Cecropieae (Urticaceae). This study elucidates the processes that lead to such floral conditions by comparing the morphology of the developing flowers of Cecropia pachystachya, Coussapoa microcarpa and Pourouma cecropiifolia. Buds and flowers were examined under scanning electron and light microscopy. The tubular calyx originates from the activity of a peripheral annular meristem that results in a tube with two or three lobes. In the staminate floral meristem, the androecium primordium arises as a central bulge that elongates and originates two stamens with the filaments basally or totally united; the anthers can also be united. In the pistillate floral meristem, the gynoecium primordium also arises as a central bulge that elongates and originates two carpel primordia: one expands, forming a cleft and an ovule, and the other does not differentiate and remains rudimentary. Pistillate and staminate flowers result from the absence of the stamen or carpel, respectively, from inception. Petals are also absent from inception. The formation of the tubular calyx and connate stamens occurs very early in development, characterizing a congenital union. The union of anthers by the connectives in C. microcarpa is postgenital and occurs between epidermal cell walls through a weak cohesion. The floral development of Cecropieae is quite similar and less labile than in the other Urticaceae species.
... According to contemporary molecular research (SYTSMA et al., 2002;YANG et al., 2013), Cannabaceae family includes 8 more genera besides hemp and hop: Aphananthe, Gironniera, Lozanella, Celtis, Pteroceltis, Chaetachme, Trema, and Parasponia. ...
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Hemp (Cannabis sativa L.) was one of the earliest domesticated plant species. Biological classification (taxonomy or systematization) manifests evolutional relationships between taxons according to trait similarities. When it comes to taxonomy, hemp is one of the most controversial plant species due to significant effects of environmental conditions on hemp phenology and expression of quantitative traits as well as different levels of gender expression observed in hemp plants. Controversial taxonomy of hemp has gone through several phases throughout history. The attitude on the number of species within the genus Cannabis and the criteria used in taxonomic units division were under dispute. Initially focused on morphological characteristics and geographical origin, the approach was greatly amended by the development of molecular and biochemical techniques. The main cause of taxonomic uncertainties is the inbreeding ability of all wild Cannabis populations, resulting in continual variability of quantitative traits. The aim of the paper is to review the history of Cannabis classification including different approaches to this scientific issue.
... The second branch is Cannabaceae includes C. sativa and H. lupulus, which is closely to Moraceae. Studies have shown that both Cannabaceae and Moraceae belong to the Urticalean Rosid clade [44,45]. The remaining two families, Rosaceae and Fagaceae, belong to Rosanae. ...
Preprint
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Background: Broussonetia kazinoki × Broussonetia papyifera (ZJGS) is a hybrid species, which has a very complicated hybrid origin. Its excellent characteristics make it both ecological benefits and economically valuable. Results: This study aimes to further understand ZJGS and Moraceae taxa through the ZJGS chloroplast (cp) genome structure and the comparative with 12 closely related Moraceae species, especially the cross parent B. kazinoki and B. papyrifera. The analyses show that ZJGS cp genome is 160,903 bp in length. Among the 13 Moraceae species, the cp genome length of seven Broussonetia species (ranges from 160,239 bp to 162,594 bp) is larger than that of six Morus species (ranges from 158,459 bp to 159,265 bp). However, the average GC content of Broussonetia species is lower than that of Morus species, which is 35.72% and 36.26%, respectively. Compared with Moraceae species, the ZJGS cp genome has a high degree of sequence similarity with B. kazinoki and B. monoica. In the comparison of repeated sequences, ZJGS and its maternal species B. kazinoki shows similar simple sequence repeats (SSRs) frequency. Among the 77 shared protein-coding genes (PCGs) in Moraceae species, the obvious positive selection of Ka/Ks ratios acted on petD and rpl16 genes of B. kazinoki and B. papyrifera, respectively, and the Ka/Ks ratio > 3. Phylogenetic analysis based on shared PCGs from 28 species shows that ZJGS is closely related to maternal B. kazinoki. Conclusions: These findings provide data support for the origin of ZJGS hybridization, and provide genomic resources for future ZJGS resource development and molecular breeding.
... For cpDNA and ITS sequencing we used the same primer pairs as in amplification, while for ETS sequencing we used the primers 18S-E (Baldwin and Markos, 1998) and ETS-bdf1. PCR reactions and thermal cycler conditions followed Sytsma et al. (2002). Samples were sequenced via capillary electrophoreses using an Applied Biosystems 3730XL DNA Analyzer (Thermo Fisher Scientific corporation, California, CA, USA). ...
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Salvia L. is an ideal exemplar to demonstrate prezygotic isolation mechanisms in sympatric populations due to their wellknown staminal lever mechanism. Mechanical, phenological, and ethological isolation mechanisms have been reported among sympatric species of Salvia. However, it has been shown that if closely related species are sympatric and flower at the same time, they can potentially hybridize. In this study, we describe two new hybrid species of Salvia (S. × karamanensis Celep & B.T.Drew, and S. × doganii Celep & B.T.Drew) from Turkey based on morphological and molecular evidence. Salvia × karamanensis (S. aucheri Benth. subsp. canescens (Boiss. & Heldr.) Celep, Kahraman & Doğan × S. heldreichiana Boiss. ex Benth.) is known from near Karaman city in the central Mediterranean region of Turkey, and S. × doganii (S. cyanescens Boiss. & Bal. × S. vermifolia Hedge & Hub.-Mor.) occurs near Sivas in central Anatolia, Turkey. Morphological comparisons between the hybrid species and their putative parents are given with notes on the International Union for Conservation of Nature (IUCN) red list categories, biogeography and ecology of the two hybrid species.
... Currently, there are several phylogenies of Cannabaceae (Ueda et al. 1997;Wiegrefe et al. 1998;Song et al. 2001;Sytsma et al. 2002;Wang et al. 2009;Yang et al. 2013;Zhang et al. 2011Zhang et al. , 2018Jin et al. 2020); however, all include a reduced number of neotropical accessions, especially related to the Neotropical Celtis (Sattarian 2006;Yang et al. 2013;Chamorro et al. 2019). Sattarian (2006) stated that there is no strong group for African and Asian species of Celtis, and, despite that there is a good support for South American species, better DNA sequence markers are needed for a better-resolved phylogeny. ...
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This study provides a preliminary phylogeny of the Celtis species from the neotropical region with emphasis on the South American species. We analyzed 19 taxa using the plastid psbA-trnH and nuclear ITS 4-5, and FA16180b markers. The sequence data were analyzed using maximum parsimony, maximum likelihood, and Bayesian inference. The South Ameri- can species were highly supported as monophyletic, while the North American species were recovered as paraphyletic. The endocarp morphology corroborated the lineages within the molecular phylogeny and helps to differentiate the species, to recognize a new species Celtis serratissima, and to reestablish two previously known species, Celtis clausseniana (Wedd.) Miq. and Celtis spinosissima (Wedd.) Miq. These three species emerged among one of the three lineages of the tropical South American species. Celtis serratissima is thus described, illustrated, and compared to its most closely related species.
... (15) 大麻科. 大麻属(Cannabis L.)从桑科(Moraceae)中拆分出, 独立为大麻科(Cannabaceae) [25] . 药典 基源物种大麻(Cannabis sativa L.)为大麻科药用植物. ...
... Mediterranean hackberry (Celtis australis L.) belongs to the Cannabaceae family [83] and grows in the Mediterranean area and in parts of South-East Asia [84]. The fruits are rarely enjoyed fresh. ...
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Phenolic compounds are well-known bioactive compounds in plants that can have a protective role against cancers, cardiovascular diseases and many other diseases. To promote local food development, a comprehensive overview of the phenolic compounds' composition and their impact on human health from typical Mediterranean plants such as Punica granatum L., Ziziphus jujuba Mill., Arbutus unedo L., Celtis australis L., Ficus carica L., Cynara cardunculus var. Scolymus L. is provided. Moreover, the potential use of these data for authenticity determination is discussed. Some of the plants' phenolic compounds and their impact to human health are very well determined, while for others, the data are scarce. However, in all cases, more data should be available about the content, profile and health impacts due to a high variation of phenolic compounds depending on genetic and environmental factors. Quantifying variation in phenolic compounds in plants relative to genetic and environmental factors could be a useful tool in food authentication control. More comprehensive studies should be conducted to better understand the importance of phenolic compounds on human health and their variation in certain plants.
... Historically, the taxonomic classification of Cecropia was a subject of debate [11,25] due to its inclusion in the Moraceae, Urticaceae, and Cecropiaceae families [25][26][27][28][29]. Recently, molecular phylogenetic studies [10,11,[30][31][32][33][34][35][36] positioned this genus in the tribe Cecropieae Dumort. of the Urticaceae family [9]. Cecropieae represents a monophyletic group [10] that includes dioecious trees, shrubs, and hemiepiphytes with spiral phyllotaxis, amplexicaul stipules, a reduced system of clear latex-bearing canals, aerial or stilt roots, terminal inflorescences, and staminate flowers with straight filaments [11]. ...
Article
This work covers a systematic review of literature about the genus Cecropia from 1978 to 2020, emphasizing the analysis of 10 of the most relevant species and their associated biological activities. Cecropia is a neotropical genus, which comprises about 61 native species in the American continent where it is known to be part of the traditional medicine of numerous countries. Secondary metabolites described for this genus showed an elevated structural and functional diversity, where polyphenols have been the most abundant. Based on this diversity, Cecropia phytochemicals represent an important source of potential therapeutic agents yet to be exploited. This review also highlights the effectiveness of combining chemometrics and ultra-performance liquid chromatography-tandem mass spectrometry as a novel approach to successfully single out Cecropia species phytochemicals. While the medicinal use of Cecropia species is officially recognized in National Pharmacopoeias and Formularies of several Latin American countries, it is important to recognize that these phytomedicines are complex mixtures requiring a thorough understanding of their chemical composition and their correlation with biological activities to guarantee their quality, safety, and efficacy.
... The genetic variability and morphological features finally gave the supporting evidence for the separation of Ulmaceae and Celtidaceae (Zavada and Kim, 1996). The APG III System (Angiosperm Phylogeny Group, 2009) placed Celtis in Cannabaceae, while there seems to be strong molecular phylogenetic support for placing Celtis in Cannabaceae by different investigators (Sytsma et al., 2002;Zhang et al., 2018). Mapping of DNA of 11 genera of Ulmaceae has placed Celtis in Celtidaceae and suggested that Cannabaceae might be classified within Celtidaceae (Susan et al., 1998). ...
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A new species of Celtis toka (Family Cannabaceae) from Faifa, Saudi Arabia is described and illustrated. Morphological descriptions with a distribution map and photograph of the species were provided. Celtis toka is only recorded from West and Middle of the Sahel region and East Tropical Africa to Yemen in Arabian Peninsula. This record conceded as the second locations for the Arabian Peninsula.
... The phylogenetic analysis of Rosales revealed that Elaeagnaceae are sister to Barbeyaceae. Elaeagnaceae in a clade composed of Barbeyaceae and Rhamnaceae, Rosaceae were sister to other Rosales, which were similar with previous studies (Sytsma et al. 2002;Wang et al. 2009;Zhang et al. 2011). The remainder of the order comprises two subclades; (i) Ulmaceae are sister to Cannabaceae plus (Boehmeria and Moraceae); (ii) Rhamnaceae are sister to Elaeagnaceae plus Barbeyaceae. ...
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Plastomes, which are maternally inherited and show a moderate rate of evolution, play a critical role in phylogenetic reconstruction and assignment of plant species. However, little is known about the sequence divergence and molecular evolutionary patterns of plastid genomes in Elaeagnus mollis, a plant of great economic, medicinal, edible and ecological values. The plastid genome of E. mollis is 152,224-bp long and has 47 repeat sequences, including tandem (17), dispersed (12), and palindromic (18) types of repeat variations. Here, we reported six divergence hotspots (atpH-atpI, petN-psbM, trnT-psbD, trnP-psaJ, rpl32-trnL and ycf1) that could potentially be used as molecular genetic markers for population genetics and phylogenetic studies of E. mollis. A comparison of plastid genomes in the order Rosales showed that the trnH gene was duplicated only in Elaeagnaceae; therefore, it is an important marker in Elaeagnaceae. Phylogenetic analyses based on whole plastid genome sequences in 33 species revealed that Rosales is divided into two strongly supported clades and that the families Elaeagnaceae and Barbeyaceae are closely related.
... In other Cannabaceae species such as Cannabis sativa (Payer, 1857;Leme et al., 2020a) and Humulus lupulus (Shephard et al., 2000), diclinous flowers result from the absence of stamens/carpels from inception. Absence since inception (Granville, 1971;Sattler, 1973;Maier et al., 1997;Basso-Alves et al., 2014; and abortion (Payer, 1857;Okamoto et al., 1992;Basso-Alves et al., 2014;Leite et al., 2018;Leme et al., 2018) occur extensively in species of Rosales, especially in the Urticalean clade (Cannabaceae, Moraceae, Ulmaceae, and Urticaceae, Sytsma et al., 2002) (see Table 2). Therefore, abortion and absence from inception can occur in the same family, genera, or species (different floral morphs), providing sources of floral diversification in the group (see Endress, 2011). ...
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Premise: Celtis is the most species-rich genus of Cannabaceae, an economically important family. Celtis species have been described as wind-pollinated and andromonoecious. However, the andromonoecy of Celtis has been debated because there are reports of monoclinous flowers with non-opening anthers on short filaments. Our objective was to study the floral morphogenesis of Celtis to establish the breeding system and to better understand the developmental patterns that lead to the formation of reduced flowers in the genus. Methods: Flowers and floral buds of Celtis species were studied using scanning electron microscopy, high-resolution x-ray computed tomography, and light microscopy. Results: All flowers initiate stamens and carpels during early floral development, but either stamens or carpels abort during later stages. Thus, at anthesis, flowers are either functionally pistillate or functionally staminate. In pistillate flowers, stamens abort late and become staminodes with normal-looking anthers. These anthers have no functional endothecium and, in most of the species studied, produce no viable pollen grains. The gynoecium is pseudomonomerous, and its vascularization is similar in the sampled species. In staminate flowers, the gynoecium aborts early resulting in small pistillodes. No vestiges of petals were found. Conclusions: The species studied are monoecious and not andromonoecious as described earlier. The absence of petals, the carpel and stamen abortion, and the pseudomonomerous gynoecium result in the reduced flowers of Celtis species. The use of high-resolution x-ray computed tomography was essential for a more accurate interpretation of ovary vascularization, confirming the pseudomonomerous structure of the gynoecium.
... However, these taxa have subsequently been segregated as independent families (Angiosperm Phylogeny Group, 2016;Tokuoka, 2007;Wurdack & Davis, 2009;Wurdack et al., 2004Wurdack et al., , 2005. With regard to Urticaceae, it is here circumscribed to include Cecropiaceae, following Sytsma et al. (2002) and the Angiosperm Phylogeny Group (2016). Whereas Euphorbiaceae and its segregates are all closely related families within the Malpighiales, the distantly related Urticaceae belongs to the Rosales. ...
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Trees or tree-like plants are defined here broadly as perennial, self-supporting plants at least 5 m tall, without considering ascending leaves or inflorescences, and with 1 or several erect stems with a diameter of at least 10 cm. In this fourth contribution of the taxonomic compilation of Mexico’s native tree species, 178 species are presented: 134 in the family Euphorbiaceae (53% endemic), 1 in the Peraceae (not endemic), 12 in the Phyllanthaceae (none endemic), 1 in the Picrodendraceae (endemic), 3 in the Putranjivaceae (1 endemic), and 27 in the Urticaceae (7% endemic). The tallest tree species are Tetrorchidium rotundatum (Euphorbiaceae) reaching 45 m, and Hieronyma alchorneoides (Phyllanthaceae) being over 40 m, as reported on herbarium labels or in the literature. All species are listed in an appendix that includes the original publication, references of taxonomic revisions or floristic treatments, in some cases synonyms, existence of subspecies or varieties, maximum height in Mexico, and an indication if the species is endemic to Mexico. Enriquebeltrania (Euphorbiaceae) is the only endemic genus in these families.
... Asymmetrical change in dispersal mode is likely to be a more general pattern across angiosperms. Changes to biotic dispersal have been demonstrated to be favored in the large monocot clade (Givnish et al., 2005), as well as in some other eudicot lineages (Givnish, 1999;Smith, 2001;Sytsma et al., 2002;Lagomarsino et al., 2016). ...
... Humulus lupulus, hops, is a member of the Cannabaceae family of which Cannabis sativa, industrial hemp, belongs (Sytsma et al., 2002). Industrial hemp is a well-documented source of biomass for use in papermaking (Dutt et al., 2008, Groot et al., 1995Danielewicz and Surma-Slusarska, 2010;Tutuş et al., 2016;Abdul-Karim et al., 1995). ...
Article
The growth in the Humulus lupulus L. or hops industry, a perennial species, driven by demand from brewers has had annual revenue growth of 11.3% since 2015 making it one of the fastest growing agricultural commodities in the Pacific Northwest (PNW). There is currently 85,000 MT per year of hop bine in the PNW available for paper making. The land dedicated to hop agriculture increased by 68% from 2010 to 2019 in the Yakima Valley. The plant Humulus lupulus L. belongs to the same family as Cannabis sativa L., industrial hemp, which has seen practical use in both the paper industry and in the biobased development. The bulk density of the hop bine is low, 0.296 g/cm3 and only 1.5 metric tons of bine is produced per acre each year. However, as crops allocated to production of renewable resources compete for land previously dedicated to food crops, the residual biomass from hop cultivation offers an inexpensive alternative source of renewable lignocellulosic biomass without cannibalizing a food crop. H. lupulus was characterized to evaluate the acceptability for use as a paper making fiber and for hydrolytic conversion to biobased products. The high carbohydrate content, 58%, is similar to other lignocellulosic materials suitable for bioenergy feedstocks. The fiber has morphological characteristics similar to hardwood with length and width centered around 0.85 mm and 16.5 µm, respectively. The tensile strength of the hop-made papers was 61% greater than the industrial hemp made papers at the same refining level. This fiber presents a sustainable multi-use commodity with excellent application in biobased products and paper making which would otherwise be lost.
... respectively). Among all 13 outgroups, Hemiptelea was confirmed to be the most genetically divergent, and this is consistent with earlier studies (Ueda et al., 1997;Sytsma et al., 2002;Zhang et al., 2021), being a sister of the Ulmus and Zelkova genera. Profiles for the effective population size (N e ) are shown in the four Skyline plots in Figure 6 (it was not possible to calculate a Skyline plot for the Spanish population due to the lack of informative variations). ...
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Riparian ecosystems, in long-time developed regions, are among the most heavily impacted by human activities; therefore, the distribution of tree riparian species, such as Ulmus laevis , is highly affected. This phenomenon is particularly relevant at the margins of the natural habitat of the species, where populations are small and rare. In these cases, it is difficult to distinguish between relics or introductions, but it is relevant for the restoration of natural habitats and conservation strategies. The aim of this study was to study the phylogeography of the southern distribution of the species. We sequenced the entire chloroplast (cp) genomes of 54 individuals from five sampled populations across different European regions to highlight polymorphisms and analyze their distribution. Thirty-two haplotypes were identified. All the sampled populations showed private haplotypes that can be considered an indicator of long-term residency, given the low mutation rate of organellar DNA. The network of all haplotypes showed a star-like topology, and Serbian haplotypes were present in all branches. The Balkan population showed the highest level of nucleotide and genetic diversity. Low genetic differentiation between populations was observed but we found a significant differentiation among Serbia vs. other provenances. Our estimates of divergent time of U. laevis samples highlight the early split of above all Serbian individuals from other populations, emphasizing the reservoir role of white elm genetic diversity of Serbian population.
... The most notable finding from our two-locus phylogenetic analysis was the reconstruction of Hesperocnide as polyphyletic, consistent with Huang et al. (2019). Our current CP genome + nrDNA analysis and prior molecular studies, however, recovered Hesperocnide as monophyletic (Kim et al., 2015), with a close relationship to Urtica (Sytsma et al., 2002;Hadiah et al., 2008;Deng et al., 2013;Wu et al., 2013;Kim et al., 2015). The polyphyletic results from the two-locus tree can be ascribed to the sampling of members of the second species that were absent in the plastome analysis. ...
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Urticeae s.l, a tribe of Urticaceae well-known for their stinging trichomes, consists of more than 10 genera and approximately 220 species. Relationships within this tribe remain poorly known due to the limited molecular and taxonomic sampling of previous studies, and chloroplast genome (CP genome/plastome) evolution is still largely unaddressed. To address these concerns, we used genome skimming data—CP genome and whole nuclear DNA (18S-ITS1-5.8S-ITS2-26S); 106 accessions—for the very first time to attempt resolving the recalcitrant relationships and to explore chloroplast structural evolution across the group. Furthermore, we assembled a taxon rich two-locus dataset of trnL-F spacer and nuclear ITS (nrITS) sequences across 291 accessions to complement our genome skimming dataset. We found that Urticeae plastomes exhibit the tetrad structure typical of angiosperms, with sizes ranging from 145 to 161 kb and encoding a set of 110 to 112 unique genes. The studied plastomes have also undergone several structural variations, including inverted repeat (IR) expansions and contractions, inversion of the trnN-GUU gene, losses of the rps19 gene, and the rpl2 intron, and the proliferation of multiple repeat types; 11 hypervariable regions were also identified. Our phylogenomic analyses largely resolved major relationships across tribe Urticeae, supporting the monophyly of the tribe and most of its genera except for Laportea, Urera, and Urtica, which were recovered as polyphyletic with strong support. Our analyses also resolved with strong support several previously contentious branches: (1) Girardinia as a sister to the Dendrocnide-Discocnide-Laportea-Nanocnide-Zhengyia-Urtica-Hesperocnide clade and (2) Poikilospermum as sister to the recently transcribed Urera sensu stricto. Analyses of the taxon-rich, two-locus dataset showed lower support but was largely congruent with results from the CP genome and whole nuclear DNA dataset. Collectively, our study highlights the power of genome skimming data to ameliorate phylogenetic resolution and provides new insights into phylogenetic relationships and chloroplast structural evolution in Urticeae.
... Together, Cannabis and Humulus have long been recognized to compose the family Cannabaceae. However, based on recent phylogenetic studies, Cannabaceae is currently considered to include eight additional genera of mostly tropical trees (9,113). ...
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Cannabis sativa L. is an important yet controversial plant with a long history of recreational, medicinal, industrial, and agricultural use, and together with its sister genus Humulus, it represents a group of plants with a myr-iad of academic, agricultural, pharmaceutical, industrial, and social interests. We have performed a meta-analysis of pooled published genomics data, and 20.1
... Together, Cannabis and Humulus have long been recognized to compose the family Cannabaceae. However, based on recent phylogenetic studies, Cannabaceae is currently considered to include eight additional genera of mostly tropical trees (9,113). ...
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Cannabis sativa L. is an important yet controversial plant with a long history of recreational, medicinal, industrial, and agricultural use, and together with its sister genus Humulus, it represents a group of plants with a myriad of academic, agricultural, pharmaceutical, industrial, and social interests. We have performed a meta-analysis of pooled published genomics data, and we present a comprehensive literature review on the evolutionary history of Cannabis and Humulus, including medicinal and industrial applications. We demonstrate that current Cannabis genome assemblies are incomplete, with ∼10% missing, 10–25% unmapped, and 45S and 5S ribosomal DNA clusters as well as centromeres/satellite sequences not represented. These assemblies are also ordered at a low resolution, and their consensus quality clouds the accurate annotation of complete, partial, and pseudogenized gene copies. Considering the importance of genomics in the development of any crop, this analysis underlines the need for a coordinated effort to quantify the genetic and biochemical diversity of this species.
... The authors explained that the differences might be attributed to evolutionary tendencies due to the diversification of polyphenolics in them. In addition, they also related the advent and disappearance of the signals as temporary sequences due to genetic changes that help us in acknowledging the modifications; hence, this corroborates other classifications of phylotaxonomy [106,107]. The concept can be further extended to the subcellular analysis of plants, with outstanding data enabling further manipulation of the essential constraints for improving health and product outcomes using plants. ...
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The profiling, or fingerprinting, of distinct varieties of the Plantae kingdom is based on the bioactive ingredients, which are systematically segregated to perform their detailed analysis. The secondary products portray a pivotal role in defining the ecophysiology of distinct plant species. There is a crucial role of the profiling domain in understanding the various features, characteristics, and conditions related to plants. Advancements in variable technologies have contributed to the development of highly specific sensors for the non-invasive detection of molecules. Furthermore, many hyphenated techniques have led to the development of highly specific integrated systems that allow multiplexed detection, such as high-performance liquid chromatography, gas chromatography, etc., which are quite cumbersome and un-economical. In contrast, electrochemical sensors are a promising alternative which are capable of performing the precise recognition of compounds due to efficient signal transduction. However, due to a few bottlenecks in understanding the principles and non-redox features of minimal metabolites, the area has not been explored. This review article provides an insight to the electrochemical basis of plants in comparison with other traditional approaches and with necessary positive and negative outlooks. Studies consisting of the idea of merging the fields are limited; hence, relevant non-phytochemical reports are included for a better comparison of reports to broaden the scope of this work.
... The genera Cannabis L. and Humulus L. belong to the Cannabaceae family in which eight more genera (Celtis, Pteroceltis, Aphananthe, Chaetachme, Gironniera, Lozanella, Trema, and Parasponia spp.) have recently been included based on phylogenetic studies [1,2]. ...
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In this study, essential oils (EOs) and hydrolates (Hys) from Italian hemp (Cannabis sativa L. Kompolti cv.) and hop (Humulus Lupulus L., Chinook cv.) supply chains were chemically characterized and tested to investigate their apoptotic potential for the first time. Headspace–Gas Chromatography–Mass Spectrometry (HS-GC-MS) techniques were performed to describe their volatile chemical profile, highlighting a composition rich in terpene derivatives such as monoterpenes and sesquiterpenes among which β-myrcene, limonene, β-caryophyllene and α-humulene were the main constituents of EOs; in contrast, linalool, cis-p-menth-2,8-dien-1-ol, terpinen-4-ol, α-terpineol, caryophyllene oxide, and τ-cadinol were found in the Hys. The cytotoxicity activity on human leukemia cells (HL60), human neuroblastoma cells (SH-SY5Y), human metastatic adenocarcinoma breast cells (MCF7), human adenocarcinoma breast cells (MDA), and normal breast epithelial cell (MCF10A) for the EOs and Hys was studied by MTT assay and cytofluorimetric analysis and scanning and transmission electron microscopy were performed to define ultrastructural changes and the mechanism of cells death for HL 60 cells. An induction of the apoptotic mechanism was evidenced for hemp and hop EOs after treatment with the corresponding EC50 dose. In addition, TEM and SEM investigations revealed typical characteristics induced by the apoptotic pathway. Therefore, thanks to the integration of the applied methodologies with the used techniques, this work provides an overview on the metabolomic profile and the apoptotic potential of hemp and hop EOs and, for the first time, also of Hys. The findings of this preliminary study confirm that the EOs and Hys from Cannabis and Humulus species are sources of bioactive molecules with multiple biological effects yet to be explored.
... The most notable finding from our two-locus phylogenetic analysis was the reconstruction of Hesperocnide as polyphyletic, consistent with Huang et al. (2019). Our current CP genome + nrDNA analysis and prior molecular studies, however, recovered Hesperocnide as monophyletic , with a close relationship to Urtica (Sytsma et al., 2002;Hadiah et al., 2008;Deng et al., 2013;Wu et al., 2013;. The polyphyletic results from the two-locus tree can be ascribed to the sampling of members of the second species that were absent in the plastome analysis. ...
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Pimpinella species are annual, biennial, and perennial semibushy aromatic plants cultivated for folk medicine, pharmaceuticals, food, and spices. The karyology and genome size of 17 populations of 16 different Pimpinella species collected from different locations in Iran were analyzed for inter-specific karyotypic and genome size variations. For karyological studies, root tips were squashed and painted with a DAPI solution (1 mg/ml). For flow cytometric measurements, fresh leaves of the standard reference (Solanum lycopersicum cv. Stupick, 2C DNA = 1.96 pg) and the Pimpinella samples were stained with propidium iodide. We identified two ploidy levels: diploid (2x) and tetraploid (4x), as well as five metaphase chromosomal counts of 18, 20, 22, 24, and 40. 2n = 24 is reported for the first time in the Pimpinella genus, and the presence of a B-chromosome is reported for one species. The nuclear DNA content ranged from 2C = 2.48 to 2C = 5.50 pg, along with a wide range of genome sizes between 1212.72 and 2689.50 Mbp. The average monoploid genome size and the average value of 2C DNA/chromosome were not proportional to ploidy. There were considerable positive correlations between 2C DNA and total chromatin length and total chromosomal volume. The present study results enable us to classify the genus Pimpinella with a high degree of morphological variation in Iran. In addition, cytological studies demonstrate karyotypic differences between P. anthriscoides and other species of Pimpinella, which may be utilized as a novel identification key to affiliate into a distinct, new genus – Pseudopimpinella.
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The genus Cecropia contains 61 species of high ecological importance in the Neotropics. Cecropia pachystachya Trécul has a wide geographic distribution and high morphological variability. The last taxonomic review of C. pachystachya was performed in 2005 and incorporated seven other Cecropia species by synonymization. However, this synonymization was not fully accepted by experts in Urticaceae because of high morphological variations in the taxon. In this study, we aimed to evaluate whether the morphological variations observed in C. pachystachya morphotypes also occurred at the DNA level and to contribute to the understanding of the evolutionary relationship between species morphotypes. Morphological analysis of eight species descriptors in 28 accessions of C. pachystachya allowed the differentiation of all five morphotypes evaluated. The analysis of the trnL-trnF (plastid) and ITS (nuclear) regions from 24 accessions by maximum parsimony, maximum likelihood, and Bayesian inference methods showed a robust molecular differentiation between C. pachystachya morphotypes. Climate was the main factor that seemed to influence clade formation in the phylogenetic trees. The higher genetic relation among morphotypes from the Amazon, Caatinga, and Cerrado regions corroborated previous hypotheses of close relationships between these biomes in past ages. The morphotype group from the Atlantic Forest seemed to be related to the proposed Pleistocene refuges to this biome. The overall analysis of morphological and molecular data shows robust differences between C. pachystachya synonymized morphotypes, which indicates the need of a taxonomic revision of the C. pachystachya complex and subsequent reinstatement of at least four synonymized species.
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Cannabis sativa is an extraordinarily versatile species. Hemp and its cousin marijuana, both C. sativa, have been used for millennia as a source of fibre, oil and for medicinal, spiritual and recreational purposes. Because the consumption of Cannabis can have psychoactive effects, the plant has been widely banned throughout the last century. In the past decade, evidence of its medicinal properties did lead to the relaxation of legislation in many countries around the world. Consequently, the genetics and development of Cannabis as well as Cannabis-derived products are the subject of renewed attention.Here, we review the biology of C. sativa, including recent insights from taxonomy, morphology and genomics, with an emphasis on the genetics of cannabinoid synthesis. Because the female Cannabis flower is of special interest as the site of cannabinoid synthesis, we explore flower development, flowering time well as the species' unique sex determination system in detail. Furthermore, we outline the tremendous medicinal, engineering, and environmental opportunities that Cannabis bears. Together, the picture emerges that our understanding of Cannabis biology currently progresses at an unusual speed. A future challenge will be to preserve the multipurpose nature of Cannabis, and to harness its medicinal properties and sustainability advantages simultaneously.
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The eudicots are a large, monophyletic assemblage of angiosperms, comprising roughly 190,000 described species, or 75% of all angiosperms. The monophyly of eudicots is well supported from molecular data and delimited by at least one palynological apomorphy: a tricolpate or tricolpate-derived pollen grain. A tricolpate pollen grain is one that has three apertures, equally spaced and approximately parallel to the polar axis of the grain. Apertures are differentiated regions of the pollen grain wall that may function as the site of pollen tube exitus as well as to allow for expansion and contraction of the pollen grain with changes in humidity. Tricolpate pollen grains evolved from a monosulcate type (having a single distal aperture, which is considered to be ancestral in the angiosperms, as well as for many seed plant clades. Many eudicots have pollen grains with more than three apertures, of a great variety of numbers, shapes, and position (constituting important taxonomic characters). These are all thought to have been derived from a tricolpate type.
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Abstract Premise Paleontologists use tooth form to assess diets of fossil mammals. Plants would also be expected to adapt their morphology to respond to herbivory. Fossil nettle leaves with definitive stinging trichomes (tribe Urticeae, family Urticaceae) are described from the early Eocene upland lacustrine floras of the Okanogan Highlands, British Columbia, Canada. This is the first report of stinging trichomes in the fossil record. Their occurrence in western North America at a time of major large herbivorous mammal radiation suggests they acted, as they do today, as a deterrent for mammal herbivory. Methods Fossil leaf compressions and extant leaves were photographed with standard methods. Focus‐shift stacking was used to layer photos of the fossil leaves. Results Urticaceous fossil leaves from the Okanogan Highlands greatly resemble their modern relatives in leaf morphology and particularly in both stinging and nonstinging trichomes. Nettles are common components of the flora of the Volcanoes National Park in Rwanda. This region is used as a modern analogue for the Okanogan Highlands, based on comparable elevation, equable conditions that host both similar floras and large folivores. Conclusions Nettles in tribe Urticeae (Urticaceae) producing leaves with stinging and nonstinging trichomes were already present in the early Eocene of western North America at a pivotal time during the early radiation of modern mammalian herbivore groups. They offer tantalizing evidence of a selective response that plants may have developed to protect themselves from the evolving mammalian herbivores of that time.
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Tapa (barkcloth) is a non-woven textile made from the inner bark of some plant species. Tapa manufacture was once widespread throughout the Pacific and tapa from the eighteenth and nineteenth century form part of Pacific collections in many museums. Here we examined the feasibility of DNA identification of the plants used to make tapa artefacts by developing and testing a DNA reference database of chloroplast trnL intron P6 loop sequences from many of the plant species used to make tapa, as well as other New Zealand textile plants. This database enabled identification to genus for most species but many species shared identical sequences. Despite the lack of species-level resolution, this technique will still aid with identifying the origins of tapa artefacts made from plants with restricted distributions, such as endemic New Zealand and Hawaiian Islands plants. A second aim was to test a number of DNA extraction methods, including non-destructive methods of interest to the heritage sector, on tapa samples. Only one of the non-destructive sampling methods produced amplifiable DNA. However, we did find variation in the success of the destructive methods tested, with the Qiagen DNeasy Plant Mini Kit having the highest success rate.
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Sorocea (Moraceae) includes approximately 25 species with a Neotropical distribution and can be recognized by being shrubs to dioecious trees with paired or solitary racemose inflorescences in the leaf axils. The number of species and the phylogenetic position of this genus are divergent according to different studies. In this work, we performed a comprehensive phylogenetic analysis of Sorocea including species after Berg’s study of the genus for the Flora Neotropica. We analysed 42 accessions of Moraceae (34 taxa), including all tribes, being 21 accessions of Sorocea (13 taxa). The phylogenetic analyses were based on plastid (trnL-F) and nuclear (ITS 4-5 and FA16180b) markers using maximum parsimony, maximum likelihood and Bayesian inference. The analyses of the combined data strongly supported the monophyly of Sorocea and its position in the Moreae tribe. The genus can be divided into three major well-supported clades, for which we described novel morphological characteristics. Morphological and phylogenetic analyses suggest the ressurection of S. jureiana, S. klotzschiana, S. racemosa and S. uaupensis as species.
Article
Background The Coussapoa genus (Urticaceae, tribe Cecropiae) contains 50 species mainly distributed throughout the Neotropical Region. Although some genera belonging to the Cecropiae tribe have been well-assessed, the chemical profile of Coussapoa members has not yet been investigated. Objective In this context, the aim of the present study was to characterize phenolic substances present in a methanol extract obtained from Coussapoa microcarpa leaves employing UPLC-DAD-ESI-MS analyses Methods Several condensed tannins (epi-afzelechin-epi-catechin, B-type and C-type procyanidins), flavan-3-ols ((+) -catechin and (-) - epicatechin), phenolic acid (O-caffeoylquinic acid) and C-glycosyl flavones (orientin, isoorientin, vitexin, isovitexin, isoorientin-2″-O-rhamnoside,vitexin-2″-O-hexoside, vitexin-2″-O-xyloside and isovitexin-2″-O-xyloside) were identified. Results The determined chemical profile observed for C. microcarpa exhibits chemo-taxonomic significance compared to other neotropical genera. Conclusion Structural variability of the identified secondary metabolites is of significant value for chemosystematic studies concerning the Coussapoa genus and the Cecropiae tribe, both still unexplored regarding their chemodiversity.
Article
Species of Broussonetia have been essential in the development of papermaking technology. In Japan and Korea, a hybrid between B. monoica and B. papyrifera (= B. × kazinoki) known as kōzo and daknamu is still the major source of raw materials for making traditional paper washi and hanji, respectively. Despite their cultural and practical significance, however, the origin and taxonomy of kōzo and daknamu remain controversial. Additionally, the long-held generic concept of Broussonetia s.l., which included Sect. Allaeanthus and Sect. Broussonetia, was challenged as phylogenetic analyses showed Malaisia is sister to the latter section. To re-examine the taxonomic proposition that recognizes Allaeanthus, Broussonetia, and Malaisia (i.e., Broussonetia alliance), plastome and nuclear ribosomal DNA (nrDNA) sequences of six species of the alliance were assembled. Characterized by the canonical quadripartite structure, genome alignments and contents of the six plastomes (160,121-162,594 bp) are highly conserved, except for the pseudogenization and/or loss of the rpl22 gene. Relationships of the Broussonetia alliance are identical between plastome and nrDNA trees, supporting the maintenance of Malaisia and the resurrection of Allaeanthus. The phylogenomic relationships also indicate that the monoecy in B. monoica is a derived state, possibly resulting from hybridization between the dioecious B. kaempferi (♀) and B. papyrifera (♂). Based on the hypervariable ndhF-rpl32 intergenic spacer selected by sliding window analysis, phylogeographic analysis indicates that B. monoica is the sole maternal parent of B. × kazinoki and that daknamu carries multiple haplotypes, while only one haplotype was detected in kōzo. Because hybridizations between B. monoica and B. papyrifera are unidirectional and have occurred rarely in nature, our data suggest that daknamu might have originated via deliberate hybrid breeding selected for making hanji in Korea. On the contrary, kōzo appears to have a single origin and the possibility of a Korean origin cannot be ruled out.
Chapter
Climate change has impacted all forms of life and its consequences are evident from altered ecological functions. Plant–microbe interactions are crucial in maintaining the ecosystem structure and driving important functions such as geochemical cycles, soil formation, carbon sequestration, and greenhouse gas emission. Microbial communities are very sensitive toward environmental stressors like temperature, moisture, pH, CO2, and any changes in the abundance, diversity, and activity of microbes which are likely to have profound impact on the associated plant communities. The plant–microbe interactions range from positive such as symbiosis to negative such as parasitism; however, benefits of microbial association certainly outnumber the negative relationships. Numerous vital physiological functions of plants supported by microbes such as nitrogen fixation, phosphate solubilization, sequestration of minerals, and conferment of stress tolerance and plant immunity can be compromised due to climate change-induced alterations in microbial community structure and dynamics. Climate change effects are also observed as shifts in phonological patterns of both plants and microbes, which can lead to serious disturbances in interspecific phenomena such as pollination, herbivory, predation, etc., threatening community stability and leading to changes in demographic processes. Plant–soil feedbacks (PSFs) play a significant role in shaping the community structure and regulating ecosystem processes. Shifts in microbial community dynamics also feedback to affect plant performance, coexistence, and community composition. PSFs also potentially modify the process of succession as the positive PSFs favoring colonization of symbiotic nitrogen fixers and mycorrhizal fungi help in establishment of primary successors on nutrient devoid substratum and the PSFs favoring decomposer community facilitate carbon cycling, soil mineralization, and nutrient mobilization, accelerating the secondary succession. The chapter discusses different aspects of plant–microbe interactions which are directly or indirectly affected by the abiotic and biotic factors influenced by climate change.
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When writing this botanical and historical review, it was necessary to get acquainted with the works of different authors from the XVII to the XXI century, written in Latin, old Spanish, old French, Spanish, French, German, Dutch, English and Russian. It shows the development of knowledge about growing on the American continents rubber-bearing trees, including their species definition and a botanical description. The main attention is paid to the Castilla elastica Cerv. from the Moraceae family, which served as a source of raw materials for the manufacture of an analogue of modern vulcanized rubber for ancient peoples of Mesoamerica and was then for many years the main rubber-bearing plant, whereas the priority have been given to Hevea brasiliensis (Wild. ex A. Juss.) Muell.-Arg. only after the beginning of plantation cultivation of this species in the end of XIX century. However, interest in Castilla did not completely disappear, and in the coming millennium, attempts were made to resume plantations. Sequencing of individual fragments of the nuclear and chloroplast genomes of Castilla species has also begun. The history of the appearance of the second erroneous name of this genus as Castilloa and the long process of returning the original name Castilla are described. Citation: Sagitov A.M., Zolkin S.Yu., Kuluev B.R., Gimalov F.R., Knyazev A.V., Chemeris A.V. Castilla elastica Cerv. is almost forgotten rubber-bearing plant. Biomics. 2021. V.13(2). P. 106-137. DOI: 10.31301/2221-6197.bmcs.2021-9
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The elm family (Ulmaceae) is a woody plant group with important scientific, societal, and economic value. We aim to present the first biogeographic synthesis investigating the global diversity, distribution, ecological preferences, and the conservation status of Ulmaceae. A literature review was performed to explore the available data for all extant species. Our study made it possible to map the actual global distribution of Ulmaceae with high precision, and to elucidate the centers of diversity, located mainly in China and in the southeastern USA. A detailed comparative analysis of the macroclimatic niche for each species was produced, which shows the general biogeographic pattern of the family and pinpoints the outlier species. The results corroborate recent molecular analyses and support the division of Ulmaceae into two taxonomically, biogeographically, and ecologically well-differentiated groups: the so-called temperate clade with 4 genera and 43 species and the tropical clade with 3 genera and 13 species. The elm family is often described as a typical temperate plant group, however the diversity peak of all Ulmaceae is located in the subtropical zone, and a non-negligible part of the family is exclusively distributed in the tropics. We also noticed that a high proportion of Ulmaceae is linked to humid macro- or microhabitats. Finally, we highlighted that nearly 25% of all Ulmaceae are threatened. Fieldwork, conservation efforts, and research activities are still necessary for this family, particularly for the tropical members and the most endangered species.
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The Macaronesian laurel forest is characterized by humidity-adapted, evergreen trees with glossy, entire and elongated leaves. Based on fossil data, this vegetation type has been regarded as a relict of Tertiary, European/Mediterranean forests since at least the middle of the 19th century. In contrast to that, more recent studies indicate that the Macaronesian laurel forest species may be much younger than previously thought, with the majority of the analyzed species dating to the Plio-/Pleistocene. Furthermore, they recovered a rather heterogeneous geographical origin, suggesting that the Mediterranean region, other Macaronesian vegetation zones as well as tropical areas have served as source areas for the corresponding species. Although previous analyses included quite characteristic taxa, e.g. all of the Macaronesian Lauraceae, only a small number (around 26%) of laurel forest genera has been studied to this day, most of them are woody. In this dissertation, the biogeography of six typical and widespread Macaronesian laurel forest genera (Daucus, Geranium, Gesnouinia, Phyllis, Semele and Visnea) is studied, covering different life-forms and ecologies. Conducting molecular phylogenetic and dating analyses as well as ancestral area estimations, a) the timeframes for the colonization of Macaronesia and the laurel forest, b) the geographical origin of the colonizers and c) the timeframes for inter-archipelago and inter-island dispersal were studied. Furthermore, the usefulness of stem ages and crown ages for inferring the colonization times is tested. Additional analyses were conducted for Gesnouinia and Visnea. In Gesnouinia, the wood anatomy was studied as the genus was considered as potentially insular woody in previous studies, which would contradict a relict status. For Visnea, fossils of the extinct V. germanica from the Miocene to Pliocene of Germany and Italy were analyzed regarding their affinity to laurel forest V. mocanera using MicroCT scans. The results obtained here provide further support for the heterogeneous origin of the Macaronesian laurel forest and indicate that stem ages should be preferred over crown ages for inferring the relict status. A relict origin of Visnea (Oligocene age) and the laurel forest taxa of Geranium (Miocene age) is very likely, whereas the situation is ambiguous in Semele and Daucus. The latter two are of Miocene age, but their phylogenetic position is poorly resolved. Laurel forest Gesnouinia and Phyllis originated within Macaronesia and are clearly no relicts from the Tertiary by their source area. Dispersal from or into the dry infra-Canarian vegetation is indicated for both genera, with the time frames differing. In Phyllis, dispersal falls into the Early Pliocene, whereas in Gesnouinia, an overlap with range-shifts associated with the Pleistocene glaciation cycles is recovered. The non-relictual trait of insular woodiness could not be unambiguously inferred for Gesnouinia. While woodiness in Gesnouinia probably is derived, it may have evolved prior to island colonization. Interarchipelago colonization between Madeira and the Canary Islands is inferred to be young in most taxa, overlapping with Pleistocene sea-level fluctuations and the timeframes recovered for species from other Macaronesian vegetation zones. The same is found for inter-island colonization within the archipelagos. For the Macaronesian laurel forest as a whole, the newly generated data as well as literature data indicate that there is likely no obvious relationship between time of colonization and life-form or time of colonization and the extant ecological niche occupied within the forest. Instead, data points towards a link between time of colonization and the main source area of the colonizers. In the humid climate of the Late Miocene, habitat conservative dispersal from the Mediterranean/Europe to newly emerged islands and habitat space created by catastrophic events seems to have predominated. In the still humid Early Pliocene, the influx from the Mediterranean/Europe decreased and the majority of colonizers originated within Macaronesia. During the Late Pliocene climatic deterioration (cooler, drier and increasing seasonal), dispersal from the Mediterranean, probably non-habitat conservatively, was prevalent. In the course of the Pleistocene (Early and Middle), climatic changes and range shifts associated with the glaciation cycles possibly promoted the arrival of a large amount of Macaronesian taxa. Pleistocene establishment is also indicated for a number of Mediterranean/European taxa, but restricted to the Early Pleistocene. Colonization events from Asia, the New World and (Eastern) Africa seem to be rare and likely occurred prior to the Pleistocene. They may have been facilitated by the lack of e.g. climatic, tectonic or marine barriers during certain periods of time.
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Species of Cannabaceae are wind pollinated, have inconspicuous and reduced flowers that are pistillate, staminate and apparently perfect on the same individual or on different individuals, with a single-whorled perianth and a pseudomonomerous gynoecium. Our objective is to understand the developmental processes that lead to such a reduced flower morphology and polygamy in Cannabis sativa, Celtis iguanaea and Trema micrantha. Floral buds and flowers were processed for surface, histological examinations and 3D reconstructions of vasculature. The single-whorled perianth is interpreted as a calyx because the organs are robust, have a broad base, an acute apex and quincuncial aestivation and are opposite the stamens. Petals are absent from inception. The dicliny is established at different development stages: stamens or carpels are absent from inception (Cannabis sativa), initiated and aborted during early (Trema micrantha, before sporo/gametogenesis) or late (Celtis iguanaea, after sporo/gametogenesis) development. Furthermore, in all species studied the carpels are congenitally united and the pseudomonomerous nature of the gynoecium is confirmed. Glandular trichomes are distributed on the bracts, sepals, anther connective and receptacle. Special floral features shared by species of Cannabaceae include precocious ovule development and sepals that are each vascularized by one bundle. The reduced flowers of Cannabaceae are the result of the absence from inception and/or abortion of organs and even of a whole whorl at different developmental stages, which were probably selected in response to pressures exerted by the similar pollination mechanism.
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The field of palynology is reviewed in terms of its contributions to angiosperm systematics and phylogeny. Principal pollen characters which are phylogenetically useful at higher taxonomic levels (including aperture type, pollen wall architecture, pollen-unit, polarity, symmetry, shape, and grain size), and their evolutionary trends are examined. Many palynological characters and concepts are subjected to re-examination, particularly in an evolutionary-phylogenetic context. An attempt is made to show how pollen characters correlate with various higher categories of the Takhtajan and Cronquist systems of angiosperm classification and to outline certain phylogenetic tends observed in the pollen of different groups of angiosperms. With some exceptions, pollen morphology is consistent with the levels of relative advancement and the relationships postulated in the Takhtajan and Cronquist systems. Angiosperm pollen grains are clearly divisible into two fundamentally different types (each with its own derivatives): heteropolar, bilateral, boat-shaped monosulcate pollen versus isopolar, radiosymmetric, globose tricolpate pollen. "Gymnospermous" monosulcate pollen and derivative types (ulcerate, disulculate, etc) characterize both the putatively primitive dicotyledonous subclass Magnoliidae and the monocotyledons. The six non-magnoliid dicotyledonous subclasses, on the other hand, are characterized by tricolpate pollen and derivative types (tricolporate, triporate, rugate etc.). Relatively primitive tricolpate pollen is retained by many Ranunculidae, Caryophyllidae, and "lower' Hamamelididae. The Dilleniidae (except Dilleniaceae) and Rosidae are somewhat more advanced in having basically compound-aperturate tricolporate pollen. The subclass Asteridae, which retains indications of a rosid ancestry, exhibits the greatest array of specialized pollen types. The most important palynological contradiction of the Takhtajan and Cronquist systems is the fact that the highly specialized, basically triporate pollen of the "higher" Hamamelididae (Amentiferae) can be more directly related to triangular tricolporate pollen of the Rosidae than to the tricolpate pollen of the "lower" Hamamelididae. Briefer sections of the paper deal with pollen technique and the major reference works of systematic palynology.
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Vestiture of Barbeya is composed of various-sized, curly, unicellular, non-glandular trichomes. Attenuate, unicellular (micropapillate), non-glandular and capitate glandular trichomes common to all Urticales are absent. Pollen of Barbeya, unlike those of Urticales, is tricolporate, but like those of some more Hamamelididae, has a stratified wall structure containing a thin, granular layer. Evidence from trichome and pollen morphology, as well as from other sources, favors a transfer of Barbeya from Urticales into its own order Barbeyales. Barbeya may be an independent offshoot from a common ancestor of Casuarinales, Fagales, Juglandales, Myricales, and Urticales.
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Parsimony analyses were conducted for 223 species representing all major groups of angiosperms using entire 18S ribosomal DNA (rDNA) sequences. Although no search swapped to completion, the topologies recovered are highly concordant with those retrieved via broad analyses based on the chloroplast gene rbcL. The general congruence of 18S rDNA and rbcL topologies further clarifies the broad picture of angiosperm phylogeny. In all analyses, the first-branching angiosperms are Amborellaceae, Austrobaileyaceae, Illiciaceae, and Schisandraceae, all woody magnoliids. These taxa are always followed by the paleoherb family Nymphaeaceae. This same general order of early-branching taxa is preserved with several suites of outgroups. In most searches, the remaining early-branching taxa represent Piperales and other orders of subclass Magnoliidae (sensu Cronquist). With the exception of Acorus, the monocots are supported as monophyletic and typically have as their sister Ceratophyllum. In most analyses, taxa with uniaperturate pollen form a grade at the base of the angiosperms; a large eudicot clade is composed primarily of taxa having triaperturate pollen. Two large subclades are present within the eudicots, one consisting largely of Rosidae and a second corresponding closely to Asteridae sensu lato. Subclasses Dilleniidae and Hamamelidae are highly polyphyletic. These data sets of 18S rDNA sequences also permit an analysis of the patterns of molecular evolution of this gene. Problems deriving from both the prevalence of indels and uncertain alignment of 18S rDNA sequences have been overstated in previous studies. With the exception of a few well-defined regions, insertions and deletions are relatively uncommon in 18S rDNA; sequences are therefore easily aligned by eye across the angiosperms. Indeed, several indels in highly conserved regions appear to be phylogenetically informative. Initial analyses suggest that both stem and loop bases are important sources of phylogenetic information, although stem positions are prone to compensatory substitutions. Of the stem changes analyzed, only 27% destroy a base-pairing couplet; 73% maintain or restore base pairing.
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Both extant subfamilies ofthe Ulmaceae have fossil records extending back to the Late Cretaceous. Extant genera, such as Ulmus, ZelkoVQ, Celtis, Aph anan the , Gironniera, and extinct genera, such as Cedrelospermwn , and Eoceltis, including both unisexual and bisexual flowers , are recognizable in the early Tertiary. Baoed upon fossil endocarps, drupes appear to he the moce ancient fruit type in the family , and the radiation of taxa with samaras, both in the Celtidoideae (Pte roceiti l), and in the Ulmoideae (e.g. Ulmus, Cedrelospermum, HemJptelea), appears to have been an early to middle Tertiary phenomenon.
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A phylogenetic analysis of 589 plastid rbcL gene sequences representing nearly all eudicot families (a total of 308 families; seven photosynthetic and four parasitic families are missing) was performed, and bootstrap re-sampling was used to assess support for clades. Based on these data, the ordinal classification of eudicots is revised following the previous classification of angiosperms by the Angiosperm Phylogeny Group (APG). Putative additional orders are discussed (e.g. Dilleniales, Escalloniales, Vitales), and several additional families are assigned to orders for future updates of the APG classification. The use of rbcL alone in such a large matrix was found to be practical in discovering and providing bootstrap support for most orders. Combination of these data with other matrices for the rest of the angiosperms should provide the framework for a complete phylogeny to be used in macro-evolutionary studies.
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Fossil twigs with attached foliage, fruits, and flowers from the middle Eocene of the Green River Formation in northeastern Utah and northwestern Colorado and from the early Oligocene Florissant beds of central Colorado provide a firm basis for reconstructing two species of an extinct ulmaceous genus that was widely distributed in the Tertiary of midlatitude western North America and Europe. Based upon combined characters of phyllotaxy, and leaf, flower, fruit, and pollen morphology, Cedrelospermum can be referred to the extant subfamily Ulmoideae, and is similar to Phyllostylon, Zelkova, and Hemiptelea. The abundance of Cedrelospermum in lake sediments of volcanic areas, together with its production of numerous small winged fruits, suggest that it was an early successional colonizer of open habitats. -from Author
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The monophyly of the group comprising the core malvalean families, Bombacaceae, Malvaceae, Sterculiaceae, and Tiliaceae, was recently confirmed by molecular studies, but the internal structure of this clade is poorly understood. In this study, we examined sequences of the chloroplast ndhF gene (aligned length 2226 bp) from 70 exemplars representing 35 of the 39 putative tribes of core Malvales. The monophyly of one traditional family, the Malvaceae, was supported in the trees resulting from these data, but the other three families, as traditionally circumscribed, are nonmonophyletic. In addition, the following relationships were well supported: (1) a clade, /Malvatheca, consisting of traditional Malvaceae and Bomba- caceae (except some members of tribe Durioneae), plus Fremontodendronand Chiranthodendron, which are usually treated as Sterculiaceae; (2) a clade, /Malvadendrina, supported by a unique 21-bp (base pair) deletion and consisting of /Malvatheca, plus five additional subclades, including representatives of Sterculiaceae and Tiliaceae, and Durionieae; (3) a clade, /Byttneriina, with genera traditionally assigned to several tribes of Tiliaceae, plus exemplars of tribes Byttnerieae, Hermannieae, and Lasiopetaleae of Sterculiaceae. The most striking departures from traditional classifications are the following: Durio and relatives appear to be more closely related to Helicteres and Reevesia (Sterculiaceae) than to Bombacaceae; several genera traditionally considered as Bombacaceae (Camptostemon, Matisia, Phragmotheca, and Quararibea) or Sterculiaceae (Chiranthodendron and Fremontodendron) appear as sister lineages to the traditional Malvaceae; the traditional tribe Hel- ictereae (Sterculiaceae) is polyphyletic; and Sterculiaceae and Tiliaceae, as traditionally circumscribed, represent polyphyletic groups that cannot sensibly be maintained with their traditional limits for purposes of classification. We discuss morpholog- ical characters and conclude that there has been extensive homoplasy in characters previously used to delineate major taxonomic groups in core Malvales. The topologies here also suggest that /Malvatheca do not have as a synapormophy monothecate anthers, as has been previously supposed but, instead, may be united by dithecate, transversely septate (polysporangiate) anthers, as found in basal members of both /Bombacoideae and /Malvoideae. Thus, ''monothecate'' anthers may have been derived at least twice, independently, within the /Bombacoideae (core Bombacaceae) and /Malvoideae (traditional Malvaceae).
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A combined analysis of 162 extant angiosperm taxa for which rbcL sequence-data and/or an appreciable amount of non-molecular information is available was calculated. A non-molecular tree, an rbcL tree, and a combined tree are presented. Only the rbcL and the combined data set show large numbers of groupings with bootstrap percentages greater than 50%, whereas the non-molecular trees show only eleven clades of this kind; this seems due to the number of missing cells in the non-molecular matrix. We tried to identify non-molecular characters (including biochemical) that support groups present in these analyses, especially in cases where clades turned out to be new when compared to one or more ''classical'' taxonomic systems. New groupings found in the non-molecular analysis that parallel the rbcL topologies include a grade containing Illiciales, Austrobaileyaceae, and Amborellaceae (magnoliid II); a clade containing Magnoliales, Laurales, Aristolochianae, and monocots (magnoliid I); a hamamelid group; subgroups of asterids (e.g., a similar asterid III clade containing Scytopetalaceae, Lecythidaceae, Sapotaceae, Ebenaceae, Theaceae, Primulales, Styracaceae, Marcgraviaceae, Actinidiaceae, Clethraceae, and Ericales); an expanded caryophyllid group; a Malvales s.l. clade; a partial Malpighiales grade containing Quiinaceae, Linales s. str., Passiflorales, Violaceae, Kiggelariaceae, Flacourtiaceae s. str., and Ochnaceae; and some smaller clades, similar to the corresponding groups found in rbcL cladograms (Illiciales-Austrobaileyaceae; Aristolochianae-monocots; Hydrangeaceae-Cornales; Lecythidaceae-Scyto- petalaceae; Pittosporaceae-Araliales; Geissolomataceae-Stachyuraceae; Connaraceae-Oxalidaceae). Capparales s.l. and the nitrogen-fixing clade, two novel molecular clades, are only found in the rbcL and the combined trees. Cistaceae have been shown to share important characters with Malvales s.l. and are consistently found within this clade. These findings argue against their previous inclusion in Violales. The rbcL tree contains 38 terminal taxa that are included for the first time in a published phylogeny. Considerable progress has been made in assembling a morphological/ chemical data set that parallels the broad coverage of angiosperms seen in DNA studies.
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Numerous phenotypic (morphological, palynological, cytological, and anatomical) studies have been conducted on Myrtales, yet the detailed relationships among the families of the order remain elusive. In this paper, the rbcL sequences of 50 taxa (39 representatives of Myrtales and 11 rosid outgroups) were analyzed using parsimony and maximum likelihood to provide a phylogenetic hypothesis of intraordinal relationships in Myrtales. The congruence between the phenotypic data from an earlier study and the rbcL topology was assessed to identify the potential synapomorphies that would corroborate the clades supported by the molecular tree. The rbcL consensus tree defined two major clades in the order. The first clade comprised a Myrtaceae lineage sister to a Melastomataceae lineage and the second clade included Onagraceae, a Lythraceae lineage, and Combretaceae. Phenotypic characters suggest that the ancestor of the first clade was characterized by the acquisition of fibrous seed exotegmen, while the ancestor of the second clade had flowers with stamens inserted directly on the rim of the hypanthium. However, branch support for the basal split of Myrtales is weak, possibly as a result of rapid early radiation in the order.
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Despite intensive morphological and chemical studies on the Myrtales, the circumscription of the order remains poorly defined. To test the monophyly of Myrtales sensu Dahlgren and Thorne (Annals of the Missouri Botanical Garden 71: 633-694, 1984), determine the relationships of some controversial families, and identify the most likely sister group of Myrtales, we conducted parsimony analyses on 80 rbcL sequences representing 36 taxa from families traditionally included in Myrtales and 44 taxa from other Rosidae. The consensus tree resulting from these analyses supports the monophyly of Myrtales and is substantially congruent with the circumscription of the order proposed by Dahlgren and Thorne (Annals of the Missouri Botanical Garden 71: 633-694, 1984), with one notable exception: in the rbcL tree Vochysiaceae are placed in Myrtales. A reanalysis of morphological attributes of Vochysiaceae revealed that the inclusion of the family in Myrtales is also supported by the combined occurrence of two typical myrtalean features of the wood: vestured pits and bicollateral vascular bundles. Furthermore, our analyses excluded Thymelaeaceae, Lecythidaceae, Haloragaceae, and Gunneraceae from Myrtales, suggesting that the association of these families with Myrtales, as previously proposed by other authors, may not reflect common ancestry. Finally, our analyses support a sister group relationship between the order Myrtales and a clade formed by an expanded Malvales, Sapindales, and an expanded Capparales.
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Rapateaceae (16 genera, ˜100 species) is largely restricted to the tepuis and sandplains of the Guayana Shield in northern South America, with Maschalocephalus endemic to West Africa. The family has undergone extensive radiation in flower form, leaf shape, habit, and habitat. To analyze the evolution of these distributions and traits, we derived a molecular phylogeny for representatives of 14 genera, based on sequence variation in the chloroplast-encoded ndhF gene. The lowland subfamily Rapateoideae is paraphyletic and includes the largely montane subfamily Saxo-fridericioideae as a monophyletic subset. Overall, the morphological/anatomical data differ significantly from ndhF sequences in phylogenetic structure, but show a high degree of concordance with the molecular tree in three of four tribes. Branch lengths are consistent with the operation of a molecular clock. Maschalocephalus diverges only slightly from other Monotremae: it is the product of relatively recent, long-distance dispersal, not continental drift—only its habitat atop rifted, nutrient-poor sandstones is vicariant. The family appears to have originated approximately 65 Mya in inundated lowlands of the Guayana Shield, followed by: (1) wide geographic spread of lowland taxa along riverine corridors; (2) colonization of Amazonian white-sand savannas in the western Shield; (3) invasion of tepui habitats with frequent speciation, evolution of narrow endemism, and origin of hummingbird pollination in the western Shield; and (4) reinvasion of lowland white-sand savannas. The apparent timing of speciation in the Stegolepis alliance about 6–12 Mya occurred long after the tepuis began to be dissected from each other as the Atlantic rifted approximately 90 Mya. Given the narrow distributions of most montane taxa, this suggests that infrequent long-distance dispersal combined with vicariance accounts for speciation atop tepuis in the Stegolepis alliance.
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This paper develops a model of private debt financing under inefficient financial intermediation. It suggests a mechanism that can generate the following sequence of events observed in the recent Asian crisis: A period of relatively low capital flow despite a steady improvement in economic fundamentals (capital inflow inertia), followed by a fast buildup of capital inflow, and ended with a large capital outflow and domestic credit crunch. Unlike other models requiring large movements in fundamentals or asset prices to explain a financial crisis, this model can exhibit large credit/capital flow swings with moderate changes in the economic and market environment.
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One table includes a statistical summary of flowering-plant taxa: c235 000 species of 12 615 genera, 440 families, and 711 subfamilies and undivided families in 28 superorders, 70 orders, and 75 suborders of Angiospermae. Three other tables summarize the indigenous distribution of the families and subfamilies of Angiospermae about the world. -from Author
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Trees or shrubs, bisexual or unisexual, with watery sap. Leaves alternate, rarely opposite, simple, usually distichous, often oblique at the base, pinnately or pinnipalmately veined, entire or dentate, petiolate; stomates anomocytic or with poorly differentiated supporting cells; cystoliths commonly present, especially in the epidermis; stipules paired, lateral, interpetiolar, or intrapetiolar, free or fused, caducous. Inflorescences axillary, cymose, racemose, paniculate, fasciculate, or the female flowers solitary. Flowers perfect of imperfect, actinomorphic to slightly zygomorphic; perianth subcampanulate, with a single whorl with (2−)4–6(−9) tepals, free or united below, persistent; petals absent. Stamens as many as the sepals and opposite them, or rarely twice as many, or up to 16, free or with the filaments arising from the calyx tube, erect in bud, anthers 2-thecous and dehiscing longitudinally, dorsifixed and often somewhat versatile, a pistillode usually persent in male flowers, staminodes present or absent in female flowers. Gynoecium composed of 2 connate carpels; ovary superior, sessile or stipitate, 1-locular or rarely 2-locular (in Ulmus spp.); style branches 2, linear, simple or bifurcate, with decurrent stigmas; ovule 1, pendulous near the apex of the locule, anatropous or amphitropous, bitegmic, crassinucellar. Fruit a drupe or samara; seeds with straight or curved, dicotyledonous embryo and scanty or no endosperm.
Article
Amino acid sequence data are available for ribulose biphosphate carboxylase, plastocyanin, cytochrome c, and ferredoxin for a number of angiosperm families. Cladistic analysis of the data, including evaluation of all equally or almost equally parsimonious cladograms, shows that much homoplasy (parallelisms and reversals) is present and that few or no well supported monophyletic groups of families can be demonstrated. In one analysis of nine angiosperm families and 40 variable amino acid positions from three proteins, the most parsimonious cladograms were 151 steps long and contained 63 parallelisms and reversals (consistency index = 0.583). In another analysis of six families and 53 variable amino acid positions from four proteins, the most parsimonious cladogram was 161 steps long and contained 50 parallelisms and reversals (consistency index = 0.689). Single changes in both data matrices could yield most parsimonious cladograms with quite different topologies and without common monophyletic groups. Presently, amino acid sequence data are not comprehensive enough for phylogenetic reconstruction among angiosperms. More informative positions are needed, either from sequencing longer parts of the proteins or from sequencing more proteins from the same taxa.
Article
The problem of the correct position of the Conocephaloideae, a subfamily of the Moraceae in Engler's system, but transferred to the Urticaceae by Corner (1962), can be satisfactorily solved by assigning the rank of family to this taxon, to be named Cecropiaceae. Diagnoses of and a key to the six genera constituting this family (Cecropia, Coussapoa, Musanga, Myrianthus, Poikilospermum, and Pourouma) are given. The classification of the Urticales and the relationship between the Cecropiaceae and both Moraceae and Urticaceae are discussed. A key to the families of the Urticales is given.
Article
Two hundred sixty-three species of the Magnoliidae distributed over the main genera of all its families were investigated with the TEM for ultrastructural characters from their sieve elements. Details from sieve-element plastids (overall diameter, as well as qualitative and quantitative measurements of their starch and protein contents) provided the main data set for a putative phylogenetic arrangement of the families of Magnoliiflorae. The recording of the presence or absence of nondispersive protein bodies and nacreous wall thickenings yielded additional information. Within the Magnoliiflorae sieve-element plastids are proposed to have evolved from large-sized S-type plastids with high amount of starch to small-sized, starch-deficient P-type or, at the other extreme, to So-plastids. Along this line a basic group containing Austrobaileyaceae, Illiciaceae, Schisandraceae, Chloranthaceae, Myristicaceae, and Winteraceae is distinguished from four parallel and slightly advanced groups, the Annona-, Aristolochia-, Magnolia-, and Monimia-groups. The Aristolochia-group is held to represent one of the core groups of the Magnoliiflorae, incorporating the whole range of the different plastid forms from S-type to So-plastids or by several steps to form-Pc and the monocotyledon form-P2c plastids. Among the remaining five the Monimia-group, only, shows a comparably broad range, while all other taxa are confined to one or two plastid forms (i.e., S-type and/or form-Psc resp. -Pcs plastids).
Article
Ultrastructural analysis of sieve tubes of Hamamelididae (48 species from 16 families and 12 of the 15 orders investigated) showed a rather uniform distribution of S-type plastids (storing starch only) among this subclass. P-type plastids (storing protein) were reported only for the genus Ulmus. Some other species belonging to the Urticales contain sieve-tube plastids storing neither starch nor protein; however, the scarce formation of minute starch grains in at least two species of the latter group joins them to the S-type plastids.
Article
Chemical data for the Hamamelidae (sensu Cronquist) are numerous but scattered. Few large-scale comprehensive surveys of any particular group of compounds (micro- or macromolecular) exist for the Hamamelidae. This has limited the use of such data in drawing broad systematic conclusions beyond those based on extant morphological, anatomical, and palynological studies. Certainly, available data for some classes of compounds, such as phenolics, have proven useful at the inter- and intrafamilial level (e.g., Ulmaceae, Juglandaceae, Urticaceae). However, the diverse and sometimes "exotic" micromolecules (e.g., alkaloids, sesquiterpene lactones, polyacetylenes, glucosinolates) often found in the other subclasses of angiosperms are mostly lacking in the Hamamelidae. This implies, at least from present surveys, a biochemical conservatism (or alternatively, reduction) for the group and an early and considerable divergence from its more chemically diverse putative Magnoliid ancestors.
Article
The family Ulmaceae is most often treated as a single family with two subfamilies: The Ulmeae (Ulmoideae) and Celteae (Celtidoideae) or, more recently, as two separate families: the Ulmaceae and the Celtidaceae (sensu Grudzinskaya). A flavonoid survey of 80 species of Ulmaceae shows that each of the 19 genera is characterized by the production of flavonols (Ulmoid) or glycoflavones (Celtoid), but not both. Further, the arrangement of genera based on this flavonoid dichotomy is remarkably compatible with the generic assignments in Grudzinskaya's bifamilial concept of the Ulmaceae. The only exceptions are Ampelocera, Aphananthe, and Gironniera (in part), which are normally considered Celtoid but possess Ulmoid (flavonols) chemistry. However, recent anatomical and morphological studies of these three genera indicate that their relationship to the Celtoid line may not be as direct as has been supposed, a point also suggested by the flavonoid chemistry.
Article
The internal transcribed spacers and 5.8S cistron of nuclear ribosomal DNA were sequenced from 22 species of Epilobium and two outgroups. Phylogenies were inferred from the sequences using parsimony, neighbor-joining, maximum-likelihood, and compatibility analysis. With parsimony we explored the effect of different weights for insertions/deletions (indels) vs. substitutions, coding vs. non-coding regions, transitions vs. transversions, and a posteriori character reweighting. Section Chamaenerion was found to be sister to the rest of the genus. The remainder of Epilobium fell into two main clades: 1) sect. Epilobium, and 2) the "xerophytic" clade, which comprises the remaining six sections. The unusual species E. rigidum (sect. Epilobium) had an uncertain position, appearing either at the base of sect. Epilobium, the base of the "xerophytic" clade, or as sister to the entire genus except sect. Chamaenerion. Within the "xerophytic" clade, relationships were incompletely resolved but a monophyletic group consisting of the annual sects. Boisduvalia and Currania (both formerly constituting the genus Boisduvalia) and the perennial, hummingbird-pollinated sect. Zauschneria was supported. The molecular phylogeny is compatible with some important independent characters and is useful for interpreting morphological and cytological evolution in Epilobium.
Article
The estimation procedure utilizes a compatibility analysis between enzyme data sets of the most parsimonious trees constructed from the restriction enzyme. Next, a non-parametric test is given for comparing alternative phylogenies. A 2nd non-parametric test is developed for testing the molecular clock hypothesis. To illustrate the power of these procedures, data derived from the mitochondrial DNA and globin DNA of man and the apes are analyzed. Although previous analyses of these data led to the speculation that 10 times more information would be required to resolve the evolutionary relationships between man with chimps and gorillas, this algorithm resolved these relationships at the 5% level of significance. The molecular clock hypothesis was rejected at the 1% level. The implications of this phylogenetic inference when coupled with other types of data lead to the conclusion that knuckle-walking - not bipedalism - is the evolutionary novelty in mode of locomotion in the primates and that many other hominid features are primitive whereas their African ape counterparts are derived.-from Author
Article
A phylogenetic analysis of a combined data set for 560 angiosperms and seven outgroups based on three genes, 18S rDNA (1855 bp), rbcL (1428 bp), and atpB (1450 bp) representing a total of 4733 bp is presented. Parsimony analysis was expedited by use of a new computer program, the RATCHET. Parsimony jackknifing was performed to assess the support of clades. The combination of three data sets for numerous species has resulted in the most highly resolved and strongly supported topology yet obtained for angiosperms. In contrast to previous analyses based on single genes, much of the spine of the tree and most of the larger clades receive jackknife support ≥50%. Some of the noneudicots form a grade followed by a strongly supported eudicot clade. The early-branching angiosperms are Amborellaceae, Nymphaeaceae, and a clade of Austrobaileyaceae, Illiciaceae, and SchiÍsandraceae. The remaining noneudicots, except Ceratophyllaceae, form a weakly supported core eumagnoliid clade comprising six well-supported subclades: Chloranthaceae, monocots, Winteraceae/Canellaceae, Piperales, Laurales, and Magnoliales. Ceratophyllaceae are sister to the eudicots. Within the well-supported eudicot clade, the early-diverging eudicots (e.g. Proteales, Ranunculales, Trochodendraceae, Sabiaceae) form a grade, followed by the core eudicots, the monophyly of which is also strongly supported. The core eudicots comprise six well-supported subclades: (1) Berberidopsidaceae/Aextoxicaceae; (2) Myrothamnaceae/Gunneraceae; (3) Saxifragales, which are the sister to Vitaceae (including Leea) plus a strongly supported eurosid clade; (4) Santalales; (5) Caryophyllales, to which Dilleniaceae are sister; and (6) an asterid clade. The relationships among these six subclades of core eudicots do not receive strong support. This large data set has also helped place a number of enigmatic angiosperm families, including Podostemaceae, Aphloiaceae, and Ixerbaceae. This analysis further illustrates the tractability of large data sets and supports a recent, phylogenetically based, ordinal-level reclassification of the angiosperms based largely, but not exclusively, on molecular (DNA sequence) data.
Article
The approximately 45 woody species of Ulmus (Ulmaceae) have been placed in five to nine sections on the basis of morphological characters. Cladistic analyses of chloroplast DNA restriction site variation were employed to examine phylogenetic relationships among 29 Ulmus accessions, including representatives from all proposed sections and subsections, and Zelkova serrata. Sufficient variation was detected to construct cladograms with branches both well-resolved and supported. The cpDNA results are largely congruent with those based on nuclear ribosomal DNA. Inclusion of 18 morphological/chemical characters further resolved relationships within the genus. Intrageneric relationships implied by the molecular and combined cladograms differ from previous classifications in a number of respects. Three species, U. crassifolia, U. serotina, and U. thomasii, which have been placed in two or three sections, were found to form a well differentiated monophyletic group (sect. Trichoptelea). The maintenance of sections Anisoptelea and Trichocarpus and the recognition of subsections Foliaceae and Glabrae within section Ulmus are not supported. The inclusion of U. mexicana, sometimes treated as the distinct genus Chaetoptelea, within Ulmus is supported. The molecular evidence supports the distinctiveness of U. rubra and the recognition of two subgenera: Oreoptelea (sects. Blepharocarpus, Chaetoptelea, and Trichoptelea s. 1.) and Ulmus (sects. Lanceifolia, Microptelea, and Ulmus).
Article
The assumptions (1) that the Hamamelidae attained their zenith in the Cretaceous and, (2) that abiotic dispersal dominated in Cretaceous angiosperms, suggest that dispersal mode could be used as a character in evaluating families questionably associated with the Hamamelidae. A review of modern dispersal characters indicates that most "lower" Hamamelids are abiotically dispersed, but that several putatively derived families (e.g., Fagaceae, Moraceae) predominantly possess biotic dispersal. In many cases the dispersal mechanisms of a family are the same in the fossil record and the present day. However, in the Juglandaceae and Fagaceae the fossil record indicates a switch in dominance from abiotic to biotic dispersal around the Cretaceous-Tertiary border. Circumstantial fossil and modern evidence suggests a similar transition in the Moraceae/Cecropiaceae/Urticaceae and possibly the Ulmaceae. Thus, modern dispersal mode may not reflect the primitive dispersal mode in a lineage. Fossil dispersal evidence supports assignment of the Juglandaceae and Fagaceae to the Hamamelidae. Circumstantial evidence suggests abiotic dispersal is plesiomorphic in the Urticaceae and in the Moraceae/Cecropiaceae/Urticaceae complex: further evidence is required. Several results are note-worthy evolutionarily: (1) dispersal modes are malleable and can change within lineages; (2) this emphasizes the importance of mosaicism in angiosperm evolution; (3) the fossil and modern records suggest that families dominated by biotic dispersal are more diverse than families dominated by abiotic dispersal; (4) the Cretaceous-Tertiary boundary marks a time of major change in dispersal mode in the angiosperms; (5) the primitive fruit morphology of the Urticales appears to be the achene; and (6) derivation of fleshy structures from extra-ovarial tissues plays an important role in the dispersal of many species of the Moraceae, Cecropiaceae, and Urticaceae.
Chapter
Trees, shrubs, climbers, or herbs, with milky or sometimes watery latex (absent in Fatoua). Leaves alternate (spiral or distichous), rarely (sub)opposite or subverticillate, most frequently simple, entire, and pinnately veined, sometimes dentate, tripliveined, palmately veined, pinnately or palmately incised, rarely pinnate or palmate, stipules present, often conspicuous and/or connate. Inflorescences bisexual or unisexual, racemose or cymose to complexly capitate (and then sometimes cup-shaped to urceolate or naviculate), or pistillate inflorescences sometimes uniflorous. Flowers unisexual, perianth simple (if present), with (0−)4(−10) free or ± fused, valvate or imbricate, persistent tepals. Staminate flowers with (1−)4(−6) stamens, with straight or inflexed, free or connate filaments, pistillode present or absent. Pistillate flowers without rudiments of stamens, ovary unilocular, superior to inferior, styles and/or stigmas one or two, ovule one, anatropous or campylotropous, (sub)apical. Fruit rarely dry, achene-like, more frequently drupaceous (exocarp often dehiscent), usually enveloped by a fleshy perianth and/or immersed in a fleshy receptacle, often the whole inflorescence forming a syncarp. Seed either large, without endosperm, or small, with endosperm.
I present a new statistical method for analysing the relationship between two discrete characters that are measured across a group of hierarchically evolved species or populations. The method assesses whether a pattern of association across the group is evidence for correlated evolutionary change in the two characters. The method takes into account information on the lengths of the branches of phylogenetic trees, develops estimates of the rates of change of the discrete characters, and tests the hypothesis of correlated evolution without relying upon reconstructions of the ancestral character states. A likelihood ratio test statistic is used to discriminate between two models that are fitted to the data: one allowing only for independent evolution of the two characters, the other allowing for correlated evolution. Tests of specific directional hypotheses can also be made. The method is illustrated with an application to the Hominoidea.
Article
Barbeya oleoides has a bitegmic, crassinucellate and anatropous ovule. The inner and outer integuments are about five layers thick and not vascularized. The endosperm is initially nuclear, to become cellular later. The mature seed coat is unspecialized, remains parenchymatic and is locally compressed, except for the exotesta and the tanniniferous endotegmen. The exotesta is perforated by distinct crateriform holes. The embryological and anatomical seed coat characters support an urticalean affinity of the Barbeyaceae.
Article
A B S T R A C T Barbeya, a monotypic genus of dioecious, arborescent dicotyledonous plants from northeast Africa and adjacent Arabia, is usually regarded as having affinities within the Urticales. It is placed either in the Ulmaceae or segregated as a closely related, monotypic family. Leaves are opposite, exstipulate, and vascularized by a single, crescent-shaped trace from a unilacunar node. Wood anatomy indicates specialization at about the same level as other Urticales. Sieve tube elements of the secondary phloem exhibit highly oblique, compound sieve plates which indicate a low level of evolutionary advancement. The vascularity of the flower is described and compared with other Urticales. Pollen is tricolporate. The relationships of the genus to Moraceae, Ulmaceae, Urticaceae, and Eucommiaceae are discussed. The totality of anatomical and morphological evidence supports the retention of the family Barbeyaceae. BARBEYA is a monotypic, arborescent, dicotyledonous genus represented by B. oleoides Schweinfurth from the dry, mountainous regions of northeast Africa and adjacent Arabia. Although the plant was first reported and thoroughly