Recent publications
Suckermouth armoured catfish (Loricariidae) are a highly speciose and diverse freshwater fish family, which bear upper and lower lips forming an oral disc. Its hierarchical organisation allows the attachment to various natural surfaces. The discs can possess papillae of different shapes, which are supplemented, in many taxa, by small horny projections, i.e. unculi. Although these attachment structures and their working mechanisms, which include adhesion and interlocking, are rather well investigated in some selected species, the loricariid oral disc is unfortunately understudied in the majority of species, especially with regard to comparative aspects of the diverse oral structures and their relationship to the ecology of different species. In the present paper, we investigated the papilla and unculi morphologies in 67 loricariid species, which inhabit different currents and substrates. We determined four papilla types and eight unculi types differing by forms and sizes. Ancestral state reconstructions strongly suggest convergent evolution of traits. There is no obvious correlation between habitat shifts and the evolution of specific character states. From handling the structures and from drying artefacts we could infer some information about their material properties. This, together with their shape, enabled us to carefully propose hypotheses about mechanisms of interactions of oral disc structures with natural substrates typical for respective fish species.
Zusammenfassung
Die bundesweiten Forschungssammlungen umfassen mehr als 150 Millionen natur-, technik- und kulturhistorische Objekte. Hinzu kommen vielfältige Sammlungen von Lebendkulturen in Bioressourcenzentren. Das Konsortium OSIRIS (Offene Sammlungs-, Informations- und Rechercheinfrastruktur) fokussiert sich darauf, das immense Potenzial dieser Sammlungen für Forschungsfragen und konkrete Anwendungen gemeinsam zu erschließen, um gesellschaftliche Veränderungsprozesse zu verstehen, mitzugestalten und eine neue Wissensökonomie zu schaffen. Der Beitrag diskutiert die Frage, was eine integrative Bibliothek des biologischen, technischen und kulturellen Sammlungswissens leisten kann.
The focus of this study has been to understand the evolutionary relationships and taxonomy of a widely distributed parapatric species pair of wild silk moths in Europe: Saturnia pavonia and Saturnia pavoniella (Lepidoptera: Saturniidae). To address species delimitation in these parapatric taxa, target enrichment and mtDNA sequencing was employed alongside phylogenetic, admixture, introgression, and species delimita-tion analyses. The dataset included individuals from both species close to and farther away from the contact zone as well as two hybrids generated in the lab. Nuclear markers strongly supported both S. pavonia and S. pavoniella as two distinct species, with hybrids forming a sister group to S. pavoniella. However, the Maximum Likelihood (ML) tree generated from mtDNA sequencing data presented a different picture, showing both taxa to be phylogenetically intermixed. This inconsistency is likely attributable to mitonuclear discordance, which can arise from biological factors (e.g., introgres-sive hybridization and/or incomplete lineage sorting). Our analyses indicate that past introgressions have taken place, but that there is no evidence to suggest an ongoing admixture between the two species, demonstrating that the taxa have reached full postzygotic reproductive isolation and hence represent two distinct biological species. Finally, we discuss our results from an evolutionary point of view taking into consideration the past climatic oscillations that have likely shaped the present dynamics between the two species. Overall, our study demonstrates the effectiveness of the target enrichment approach in resolving shallow phylogenetic relationships under complex evolutionary circumstances and that this approach is useful in establishing robust and well-informed taxonomic delimitations involving parapatric taxa.
During the Paleogene, the Holarctic experienced drastic climatic oscillations, including periods of extensive glaciation. These changes had a severe impact on both the !ora and fauna causing widespread extinction and range shifts with some taxa retreating to refugia in the Mediterranean Basin. Here we provide evidence for this hypothesis using fossils from the pseudoscorpion family Garypinidae Daday, 1889 (Arachnida: Pseudoscorpiones). This family comprises 21 extant genera from all continents except Antarctica but is restricted to low mid-latitudes (<44�N) in the Northern Hemisphere. We provide the second record of garypinids from the European succinite ambers of the Eocene by describing the "rst extinct genus in Garypinidae, Baltamblyolpium gen. nov., which includes two species: Baltamblyolpium gizmotum sp. nov. from Baltic amber and Baltamblyolpium grabenhorsti sp. nov. from Bitterfeld amber. The new genus exhibits a morphology that closely resembles Neoamblyolpium Hoff, 1956 from western North America and the genus Amblyolpium Simon, 1898, which is widespread but includes taxa restricted to Mediterranean refugia in Europe. The discovery of a new fossil genus of Garypinidae from Europe con"rms that the family was found at more northerly latitudes during the Eocene, however, extinction and range contraction resulted in their present-day relictual distribution in southern Europe like many other lineages that once thrived in the European “Baltic amber forest” of the Eocene.
The United Arab Emirates (UAE) faces the challenge of balancing rapid economic development with environmental preservation and conservation in the Anthropocene era. The nation’s unique ecosystems, characterized by arid desert, rugged mountains, and diverse marine habitats, are vulnerable to disturbances such as urbanization, habitat degradation, groundwater extraction and climate change. To chart a more sustainable course for the Emirates by 2050, the paper proposes policy recommendations such as adopting a national strategy for sustainable development, strengthening environmental policies, investing in urban planning and design, promoting sustainable water management, encouraging use of nature-based solutions, addressing climate change, fostering environmental education, supporting research in environmental sciences, encouraging national and regional cooperation, promoting sustainable business practices in the private sector, and monitoring the progress of environmental policies. By embracing a vision of development that respects the natural environment and safeguards its plant and animal life, the UAE can demonstrate its commitment and serve as a model for other nations to follow, becoming a shining example of responsible development by 2050.
This chapter discusses the flora of the United Arab Emirates (UAE), focusing on various aspects of the individual plant species. A brief overview of salient features of the flora is given in terms of species number and families, followed by a short discussion regarding some of the taxonomic problems surrounding the naming and identification of species. With respect to biogeographical aspects, it is emphasised that the current flora of the nation represents a distinct snapshot in time that has been shaped by a diversity of events in the past, all of which continue to operate on different spatio-temporal scales. After a brief discussion of keystone and foundation species in the UAE desert, autecological aspects are examined, as these are fundamental to understanding the response of plants to a changing environment. Following on from this topic, the concepts of life forms, plant functional groups and plant strategies are touched upon. In the final section, some remarkable features of the reproductive biology of desert plants are described. Chapter 5 examines the typical plant communities and also looks at the main threats to the flora and vegetation of the country.
This chapter discusses the terrestrial vegetation of the United Arab Emirates, and the main units are described in the context of broad habitat types. Despite the huge increase in human activity over the past decades, natural terrestrial habitat types continue to occupy, by far, the larger part of the country. However, they are often severely degraded. The main issues affecting the flora and vegetation are largely the same as in other arid parts of the world, with overgrazing remaining a serious challenge. With regard to tackling these major issues, the various emirates have begun to create a network of protected areas. Effective management plans are required to ensure that they fulfil their role in protecting the natural heritage of the country. If rigorously implemented, the recently introduced ‘grazing law’ in Abu Dhabi emirate could create a useful blueprint for a sustainable grazing regime outside of the protected areas, leading to an enhancement of ecosystem functioning over the longer term.
Occupancy modeling is an essential tool for understanding species‐habitat associations, thereby helping to plan the conservation of rare and threatened wildlife species. The conservation status and ecology of several avian species, particularly ground‐dwelling birds, are poorly known in Ethiopia. We used camera trap‐based occupancy modeling to investigate habitat covariate influence on occupancy (Ψ) and detection probability (ρ) estimates of Moorland Francolins Scleroptila psilolaema from spatially replicated surveys across both relatively pristine and disturbed landscapes in the Afroalpine biome of Ethiopia. Model‐averaged estimate of across all sites was 0.76 (SD = 0.28) and was 0.77 (SD = 0.13) in the pristine landscape. The of the species in the disturbed landscape was 0.56 (SD = 0.19) and was 0.48 (SD = 0.06). As hypothesized, based on our model‐averaged beta coefficient estimates (β mean ± SE), predators significantly negatively influenced the occupancy of Moorland Francolins in pristine habitat. We also found a significant positive association of occupancy with herb species richness. Contrary to our prediction, distance to road significantly negatively influence the occupancy of the species, suggesting that occupancy probability was highest in proximity to roadsides and trails in the pristine habitat. There was no significant influence of habitat covariates on the occupancy of the species in the disturbed habitat. The most important covariates that significantly influence the detectability of the species in pristine habitat included sampling occasion and precipitation. The greater occupancy and detectability of this endemic species in the pristine habitat could be linked with the particular conservation status and management of this biodiversity hotspot in the central highlands of Ethiopia. Our results suggest that strict legal enforcement is required to sustainably preserve Moorland Francolins and the ecological integrity of the entire Afroalpine biome. We recommend using camera traps in order to develop realistic and effective conservation and management strategies for rare, sensitive, cryptic, and ground‐dwelling animals in the region.
Water scarcity can be considered a major stressor on land, with desiccation being its most extreme form. Land plants have found two different solutions to this challenge: avoidance and tolerance. The closest algal relatives to land plants, the Zygnematophyceae, use the latter, and how this is realized is of great interest for our understanding of the conquest of land. Here, we worked with two representatives of the Zygnematophyceae, Zygnema circumcarinatum SAG 698‐1b and Mesotaenium endlicherianum SAG 12.97, who differ in habitats and drought resilience. We challenged both algal species with severe desiccation in a laboratory setup until photosynthesis ceased, followed by a recovery period. We assessed their morphological, photophysiological, and transcriptomic responses. Our data pinpoint global differential gene expression patterns that speak of conserved responses, from calcium‐mediated signaling to the adjustment of plastid biology, cell envelopes, and amino acid pathways, between Zygnematophyceae and land plants despite their strong ecophysiological divergence. The main difference between the two species appears to rest in a readjustment of the photobiology of Zygnema , while Mesotaenium experiences stress beyond a tipping point.
Background
Venoms, which have evolved numerous times in animals, are ideal models of convergent trait evolution. However, detailed genomic studies of toxin-encoding genes exist for only a few animal groups. The hyper-diverse hymenopteran insects are the most speciose venomous clade, but investigation of the origin of their venom genes has been largely neglected.
Results
Utilizing a combination of genomic and proteo-transcriptomic data, we investigated the origin of 11 toxin genes in 29 published and 3 new hymenopteran genomes and compiled an up-to-date list of prevalent bee venom proteins. Observed patterns indicate that bee venom genes predominantly originate through single gene co-option with gene duplication contributing to subsequent diversification.
Conclusions
Most Hymenoptera venom genes are shared by all members of the clade and only melittin and the new venom protein family anthophilin1 appear unique to the bee lineage. Most venom proteins thus predate the mega-radiation of hymenopterans and the evolution of the aculeate stinger.
Twenty-two marine species of Dalytyphloplanida from Cuba, Panama, and Lanzarote are presented, sixteen of which are new to science. Five known species are recorded from Cuba: Kytorhynchus microstylus, Ceratopera paragracilis, Trigonostomum armatum, T. franki, and T. vanmecheleni. Neokytorhynchus pacificus is recorded for the first time in the Atlantic (Lanzarote). For one species, a new genus is erected to be included in a new family. A new genus and thirteen new species from Cuba and three new species from Panama are described. The new species are mainly distinguished from their congeners by the specific morphology of the copulatory structures. The new taxa are discussed in the context of a new phylogenetic analysis of Dalytyphloplanida. This analysis includes sequences of 238 species, 14 of which were sequenced for the first time. The phylogenetic analysis and the detailed morphology suggest that K. microstylus may constitute a complex of cryptic species. The internal phylogenetic relationships of Trigonostomum and Promesostoma were separately analysed to include new sequence data of the mitochondrial cox1 gene. These genera are shown to consist of several diagnosable clades, concurring with the results of early morphological studies of these taxa. Morphological and molecular data support the notion that Trigonostomum sinensis is a junior synonym of T. vanmecheleni, and we therefore propose their synonymisation. A new family is erected, Schockaertiidae fam. n., to include a monophyletic clade of neodalyellids with a pharynx rosulatus and a copulatory bulb devoid of hard structures (Schockaertia aprostatica gen. n. sp. n. and Einarella argillophyla). We propose a new classification into families of Thalassotyphloplanida, which envolves elevating the status of Adenorhynchinae to family level (Adenorhynchidae status novus). All previously recognised thalassotyphloplanid families are recovered as monophyletic (Kytorhynchidae, Byrsophlebidae, Promesostomidae, and Trigonostomidae). No support was found for the previously described subfamilies, except Paramesostominae, and we, therefore, propose to suppress these taxa.
Geometric morphometrics (GM) enable the quantification of morphological variation on various scales. Recent technical advances allow analyzing complex three-dimensional shapes also in cases where landmark-based approaches are not appropriate. Pelvic girdle bones (basipterygia) of Sulawesi ricefishes are 3D structures that challenge traditional morphometrics. We hypothesize that the pelvic girdle of ricefishes experienced sex-biased selection pressures in species where females provide brood care by carrying fertilized eggs supported by elongated pelvic fins ("pelvic brooding"). We test this by comparing pelvic bone shapes of both sexes in species exhibiting pelvic brooding and the more common reproductive strategy "transfer brooding," by using landmark-free 2D and 3D GM, as well as qualitative shape descriptions. Both landmark-free approaches revealed significant interspecific pelvic bone variation in the lateral process, medial facing side of the pelvic bone, and overall external and internal wing shape. Within pelvic brooders, the three analyzed species are clearly distinct, while pelvic bones of the genus Adrianichthys are more similar to transfer brooding Oryzias. Female pelvic brooding Oryzias exhibit prominent, medially pointing tips extending from the internal wing and basipterygial plate that are reduced or absent in conspecific males, Adrianichthys and transfer brooding Oryzias, supporting our hypothesis that selection pressures affecting pelvic girdle shape are sex-biased in Sulawesi ricefishes. Furthermore, both sexes of pelvic brooding Oryzias have overall larger pelvic bones than other investigated ricefishes. Based on these differences, we characterized two reproductive strategy-and sex-dependent pelvic girdle types for Sulawesi ricefishes. Morphological differences between the investigated pelvic brooding genera Adrianichthys and Oryzias provide additional evidence for two independent origins of pelvic brooding. Overall, our findings add to a better understanding on traits related to pelvic brooding in ricefishes and provide a basis for upcoming studies on pelvic girdle function and morphology.
Tachinidae is the second most species-rich family of Diptera. It comprises four subfamilies, and all of its members have para-sitoid habits. We present the first phylogenomic analysis of Tachinidae using transcriptomic data, based on 30 species. We constructed four datasets: three using translated data at the amino acid level (100% coverage, with 106 single-copy protein-coding genes; 75% coverage, with 1359 genes; and 50% coverage, with 1942 genes). The trees were estimated by analysing four matrices using maximum likelihood and maximum parsimony inferences, and only minor differences were found among them. Overall, our topologies are well resolved, with high node support. Polleniidae is corroborated as a sister group to Tachinidae. Within Tachinidae, our results confirm the hypothesis (Phasiinae + Dexiinae) + (Tachininae + Exoristinae). Phasiinae, Dexiinae and Exoristinae are recovered as monophyletic, and Tachininae as polyphyletic. Once again, the tribe Myiophasiini (Tachininae) composes a fifth lineage, clade sister to all the remaining Tachinidae. The Neotropical tribe Iceliini, formerly in Tachininae, is recovered within Exoristinae, sister to Winthemiini. In general, our results are congruent with recent phylogenetic studies that include tachinids, with the important confirmation of the subfamilial relationships and the existence of a fifth lineage of Tachinidae.
Pelodryadinae, the Australian tree frogs, is a monophyletic group endemic to the Australo-Papuan region. Although we have a relatively good knowledge about tadpoles' phenotypic diversity in terms of external morphology, information about internal anatomy is rare for the subfamily; for instance, their buccopharyngeal cavity is completely unknown. Herein I describe for the first time the buccopharyngeal anatomy of two pelodryadins: Litoria rubella and Ranoidea caerulea. I compare my results with available evidence from Phyllomedusidae, that is, the sister clade to Pelodryadinae, and briefly comment on buccopharyngeal cavity within Hylidae. Both species can be readily distinguished based on lateral ridge, postnarial, buccal roof arena, infralabial papillae, and lingual papillae. Variation between the two species may suggest a large diversity within Pelodryadinae. Pelodryadinae and Phyllome-dusinae present similar buccopharyngeal morphologies, although Agalychnis calli-dryas has a unique morphology and putative apomorphic transformations can be observed in Pithecopus + Phyllomedusa, Ranoidea, and Phasmahyla. K E Y W O R D S morphology, oral cavity, Phyllomedusinae, tadpole
The causes of population divergence in vagile groups remain a paradox in evolutionary biology: dispersive species should be able to colonize new areas, a prerequisite for allopatric speciation, but dispersal also facilitates gene flow, which erodes population differentiation. Strong dispersal ability has been suggested to enhance divergence in patchy habitats and inhibit divergence in continuous landscapes, but empirical support for this hypothesis is lacking. Here we compared patterns of population divergence in a dispersive clade of swallows distributed across both patchy and continuous habitats. The Pacific Swallow (Hirundo tahitica) has an insular distribution throughout Southeast Asia and the Pacific, while its sister species, the Welcome Swallow (H. neoxena), has a continental distribution in Australia. We used whole-genome data to demonstrate strong genetic structure and limited introgression among insular populations, but not among continental populations. Demographic models show that historic changes in habitat connectivity have contributed to population structure within the clade. Swallows appear to exhibit evolutionarily labile dispersal behavior in which they reduce dispersal propensity after island colonization despite retaining strong flight ability. Our data support the hypothesis that fragmented habitats enhance population differentiation in vagile groups, and suggest that labile dispersal behavior is a key mechanism underlying this pattern.
Three new genera and species of Elcanidae (Insecta: Orthoptera) are described from middle Cretaceous Myanmar amber. Paraxelcana coronakanthodis gen. et sp. nov. differs from previously known elcanids from Myanmar amber by showing cross veins in the precostal field of the forewing, as well as a unique combination of morphological features. Letoelcana artemisapollonque gen. et sp. nov. is one of only two species of Elcanidae from Myanmar amber showing two dark spots on the surface of the tegmina, but differing from the other species previously known, Hukawnelca gracile (Uchida in Cretaceous Research, 131, 2021, https://doi.org/10.1016/j.cretres.2021.105092), in a number of characters. Trigonelca jennywinterae gen. et sp. nov. features a unique new combination of metatibial spurs, as well as a triangular shaped pronotum, distinguishing it from previously known Elcanidae from Myanmar amber. We discuss possible ecological implications of wing spots (as seen on L. artemisapollonque) and the pterostigma, a specially modified wing area that appears to characteristic for many elcanid species. Based on a morphological binary character matrix from the new and already reported species, a phylogenetic tree is created, giving a hypothetical glimpse at the possible phylogeny of Elcanidae from Myanmar amber.
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