Phylogeography of the freshwater crab Potamon persicum (Decapoda: Potamidae): an ancestral ring species?

The Zagros Mountains, characterized by complex topography and three large drainage systems, harbor the endemic freshwater crab Potamon persicum in Iran. Our study delves into the evolutionary history of P. persicum, utilizing two mitochondrial and one nuclear marker. We collected 214 specimens from 24 localities, identifying 21 haplotypes grouped into two major evolutionary lineages. Substantial differentiation exists between drainage systems and lineages. Historical demographic analysis revealed a significant decrease in population size during the late Holocene, accompanied by a recent population bottleneck. Species distribution modeling has revealed eastward shifts in suitable habitats between the last glacial maximum and the present day. Following the last glacial maximum, habitat fragmentation occurred, resulting in the establishment of small populations. These smaller populations are more vulnerable to climatic and geological events, thereby limiting gene flow and accelerating genetic differentiation within species. Historical biogeographic analysis traced the origin of P. persicum to the western Zagros Mountains, with major genetic divergence occurring during the Pleistocene. Our genetic analyses suggest that P. persicum may have shown a genetic pattern similar to a classical ring species before the Pleistocene. The Namak Lake sub-basin could have served as a contact zone where populations did not interbreed but were connected through gene flow in a geographic ring. Currently, genetic separation is evident between basins, indicating that P. persicum in the Zagros Mountains is not a contemporary ring species. Also, our biogeographical analysis estimated that range evolution may have been driven initially by dispersal, and only during the late Pleistocene by vicariance.

Let's get high: Cladogenesis in freshwater crabs (Decapoda: Potamonautidae: Potamonautes) supports the mountain gradient speciation hypothesis in the Cape Fold and Drakensberg Mountains, South Africa.

During the present study, the evolutionary relationship within a clade of mountain clade of freshwater crabs (Potamonautes) was examined using mtDNA sequence data for species from the Cape Fold Mountain (CFM) and Great Escarpment (Drakensberg Mountain range). We undertook phylogenetic analyses, divergence time estimation, and an ancestral area reconstruction to explore the period of cladogenesis and understand the biogeographic history in this high-altitude clade. Furthermore, we applied four species delimitation methods using ASAP, bPTP, bGMYC, and STACEY on the latter clade. Bayesian phylogenetic analyses retrieved a monophyletic freshwater crab clade comprised of two major sister clades, one comprised of the Cape Fold (clade A) and two comprised of Drakensberg Mountains (clade B) species. Divergence time estimation indicated that the two clades underwent Mio/Pliocene cladogenesis. Within the CFM clade (A), P. amathole (Amathola Mountains) was sister to P. parvispina (Cederberg and Kouebokkeveld Mountains) and the latter species were sister to P. parvicorpus (Cape Peninsula, Jonkershoek, and Helderberg Mountains) sister to P. tuerkayi (Overberg Mountains) and P. brincki (Hottentots Holland Mountains). Within the Drakensberg Mountain clade (B), we observed in situ diversification. Specimens from the southcentral Drakensberg Mountains (Dargle Forest, Injasuti, Karkloof, and Impendle) represent a new undescribed lineage Potamonautes sp. nov. 1. The second clade from the northern Drakensberg, representing P. clarus, was sister to a central Drakensberg Mountain clade that comprised P. depressus that was in turn sister to P. baziya from the Eastern Cape Province. The application of species delimitation methods generally overestimated the number of species. The biogeographic analyses indicated that the Eastern Cape Province is the most likely ancestral range area. Ecological niche modelling of representative species in clades A (Cape Fold Mountains) and B (Drakensberg Mountains) demonstrated that temperature and rainfall were the major abiotic drivers that differentiated the two clades. Our data favours the mountain gradient speciation hypothesis.

[Forms of Use of Psychosomatic Rehabilitation by Patients - A Study on the Significance of the Moment of Entrance in the Rehabilitation Setting and the Dependence on the Individual Situation at Admission to Rehabilitation]. / Nutzungsformen psychosomatischer Rehabilitation.

BACKGROUND AND AIMS: As expectancies of patients and physicians in psychosomatic rehabilitation are not always congruent, we focused on the patients' subjective expectancies toward rehabilitation in relation to the perceived benefit of the treatment for return to work and on the individual forms of utilization of the therapeutic services in the setting of psychosomatic clinics. A special focus was given to the changes in the patients' evaluations and coping behaviours over a follow-up period of 18 months. METHODS: N=105 participants (F-3/F-4 Main-Diagnosis, specific vocational problems, under 3 months jobless) of 4 psychosomatic rehabilitation settings were asked for their situation at the end of the rehabilitation by means of a questionnaire. 33 patients out of the questionnaire-sample who consented to participate were interviewed for 3 times (6, 12 and 18 months after release from the clinic) by means of episodic-narrative interviewing technique. RESULTS: Some characteristic expectancies and modes of use of the psychosomatic rehabilitation setting by the patients could be identified. The uses of the clinics' therapeutic services by the patients are pointing to different subjective felt needs that correlate with the state of coping with the illness and other psychosocial features at the moment of entrance in the rehabilitation setting. The patients' actual situation can be identified by retrospective tracing his/her positioning on an ideal-typed trajectory of the whole illness process from the beginning of the first symptoms up to Return to work. The results give hints for more individualised and person-centred propositions in rehabilitation-settings.

Geographical range evolution of the genus Polypedates (Anura: Rhacophoridae) from the Oligocene to present.

Currently, the genus Polypedates comprises 26 species distributed in South, Southeast, and East Asia. Because of their relatively low dispersal capability and intolerance to seawater, this genus is ideal for the study of terrestrial range evolution that extends into the island archipelagos of southeastern Asia. In this study, based on data compiled for Polypedatesfrom previous studies and partial mitochondrial and nuclear genes collected in this study, we performed systematic biogeographical analysis. We confirmed a Sundaland origin for the extant genus and showed northward dispersal into mainland Southeast Asia and Asia, which coincided with the timing of paleoclimatic change from the Oligocene to Middle Miocene. Climate fluctuations had a profound impact on species diversification within the genus Polypedates. Furthermore, the Red River did not mediate species exchange between Southeast Asia and mainland Asia until the end of the Miocene, with the sudden onset of northward dispersal in several clades independently at that time. Alternatively, the lineage of widespread insular P. leucomystaxstrongly supports the hypothesis of terrestrial connection between island archipelagos of Southeast Asia during the Mid-Pleistocene paleoclimate fluctuations. Our biogeographical analysis also supports the recent introduction of P. leucomystax to the Philippines and Ryukyus, as previously suggested.

Molecular evidence for cryptic species in the common slug eating snake Duberrialutrixlutrix (Squamata, Lamprophiidae) from South Africa.

We examined the impact of climatic fluctuations on the phylogeographic structure of the common slug eating snake (Duberrialutrixlutrix) throughout its distribution in South Africa. The evolutionary history within the taxon was examined using partial DNA sequence data for two mitochondrial genes (ND4 + cyt b) in combination with a nuclear locus (SPTBN1). Phylogenetic relationships were investigated for both the combined mtDNA and total evidence DNA sequence data. In addition, population and demographic analyses together with divergence time estimations were conducted on the combined mtDNA data. Topologies derived from the combined mtDNA analyses and the total evidence analyses were congruent and retrieved five statistically well-supported clades, suggesting that Duberrial.lutrix represents a species complex. The five clades were generally allopatric, separated by altitudinal barriers and characterised by the absence of shared mtDNA haplotypes suggesting long term isolation. Divergence time estimations indicate that the diversification within the D.l.lutrix species complex occurred during the Plio/Pleistocene as a result of climatic fluctuations and habitat shifts for the species. A taxonomic revision of the D.l.lutrix species complex may be required to delineate possible species boundaries.

Asymmetric biotic interchange across the Bering land bridge between Eurasia and North America.

The exchange of biotas between Eurasia and North America across the Bering land bridge had a major impact on ecosystems of both continents throughout the Cenozoic. This exchange has received particular attention regarding placental mammals dispersing into the Americas, including humans after the last glacial period, and also as an explanation for the disjunct distribution of related seed plants in eastern Asia and eastern North America. Here, we investigate bi-directional dispersal across the Bering land bridge from estimates of dispersal events based on time-calibrated phylogenies of a broad range of plant, fungus and animal taxa. We reveal a long-lasting phase of asymmetrical biotic interchange, with a peak of dispersal from Asia into North America during the late Oligocene warming (26-24 Ma), when dispersal in the opposite direction was greatly decreased. Influx from North America into Asia was lower than in the opposite direction throughout the Cenozoic, but with peak rates of dispersal at the end of the Eocene (40-34 Ma) and again in the early to middle Miocene (16-14 Ma). The strong association between dispersal patterns and environmental changes suggests that plants, fungi and animals have likely dispersed from stable to perturbed environments of North America and Eurasia throughout the Cenozoic.

[Return to Work from Vocational RetrainingA Long-Term Analysis of Individual Trajectories: Biografical and Structural Conditions of Success and Failure]. / Von der beruflichen Vollqualifizierungsmaßnahme zurück in ArbeitEine Langzeitanalyse individueller Verlaufskarrieren und ihrer biografischen und strukturellen Bedingungen.

BACKGROUND AND AIMS: The study aimed at the reconstruction of the trajectories of participants of a two-year vocational-retraining into new workplaces thereby identifying favourable and risky conditions of the return-to-work process. From a practical point of view the study identified special needs and necessities for after-care facilities. METHODS: A Mixed-Method-Design was used. Quantitatively the follow-up-study included 214 persons who participated for three times on filling out a questionnaire over a period of eighteen months after the end of the vocational retraining. In the qualitative part of the study thirty persons consented to participate in a narrative-episodic interview on their vocational biography, their illness experiences at work and their way back into work. The study focused on the experiences of the participants from within, on their decision-making, coping, and rearrangement processes as well as on the experienced support from family members and rehabilitation professionals. RESULTS: About 75% of the participants of the vocational retraining succeeded in getting a job within the range of 18 months after finishing the retraining. Indicators for successful Return to Work are a high identification with the new vocation, effective coping with the remaining health problems, and an accepted arrangement with the disabilities in the work place and in everyday-life, a positive anticipation of the health condition in the future, and last but not least a satisfying social inclusion. As specific risk constellations for Return to Work emerged a lack of partnership, unfinished mental coping with the illness, negative subjective health prognosis, and a more passive attitude to life.

[Trajectories and Biographical Constellations in a Long-Term Study on Vocational Retraining and their Effects on Return to Work and Sustainable Stay at Work]. / Verlaufskarrieren und biografische Konstellationen beruflicher Rehabilitanden und deren Einflüsse auf Rückkehr und nachhaltigen Verbleib in Arbeit.

OBJEKTIVES: Using qualitative-hermeneutical methods with a focus on biographical (risk-) constellations for conditions of success or failure of return to work - and therefore on the efficiency and sustainability of employment participation benefits - the study accompanies participants during a time span of 2 years after their vocational retraining on their way back into the first labor market. METHODS: The study applies a mixed method design which combines 30 episodical-narrative interviews of participating rehabilitants alongside with a questionnaire survey of a total of 214 participants and 19 interviews of scientists and vocational retraining experts. RESULTS: Overall approximately 80% of the participants of our sample successfully return to work within a period of 18 months. Significant barriers can be illustrated by characteristic risk constellations, which correspond to the following dimensions: occupational choice, coping with illness, the need for protective area beyond the rehabilitation scheme, lack of (typical) life course orientation, lack of acceptance of a transitional phase with lower salary, regional occupation-specific labor market as well as social inclusion and support. CONCLUSION: Qualitative-hermeneutical methods generate - apart from diagnostic attributions and theoretical hypotheses - new factors effective for return to work with importance for rehabilitants; these factors refer to their embeddedness in processes, interrelations and interactions between biography, context factors, and administrative routines. The results identify specific needs for post-rehabilitation services supporting persons with risk constellations.

Divergent evolutionary origins and biogeographic histories of two freshwater crabs (Brachyura: Potamonautes) on the West African conveyer belt islands of São Tomé and Príncipe.

We examined the colonization history and phylogeographic structure of the two endemic freshwater crab species (Potamonautes margaritarius and P. principe) inhabiting the volcanic islands of São Tomé and Príncipe, respectively, using mitochondrial and nuclear DNA sequence data. All samples were sequenced for the mtDNA COI locus and used in the phylogeographic analyses, while a single specimen per lineage was sequenced for the two remaining loci (16S rRNA and histone 3) and used in the phylogenetic reconstruction. Phylogenetic results reveal that P. principe diverged early within a clade of East/Southern African Potamonautes during the Miocene, while P. margaritarius diverged between the Late Eocene to Early Miocene. Furthermore, the two species are not sister taxa and are distantly related. These results corroborate previously hypothesised independent transoceanic dispersal events that resulted in the establishment of the endemic freshwater crab fauna of the two islands. Within P. margaritarius, we observed two reciprocally monophyletic clades on São Tomé Island. Clade one occurred in the southeast and southwest of the island, while clade two occurred in the northeast and the northwest; the divergence between the latter two clades was estimated to be of Pleistocene age. The two clades within P. margartarius are genetically highly structured and characterised by the absence of shared maternal haplotypes, suggesting possible speciation within P. margartarius. In contrast P. principe exhibits a shallow population genetic structure. Possible mechanisms of colonization and cladogenesis in the two freshwater crabs are discussed.

A novel PAX7 10-bp indel variant modulates promoter activity, gene expression and contributes to different phenotypes of Chinese cattle.

Paired box 7 (PAX7) gene regulates the conversion of muscle satellite cells into myogenic cells and participates in multi-step processes in myogenesis. Expression levels of PAX7 are decisive for its regulatory function. Previous reports revealed that PAX7 were responsible for the developmental traits of muscle. The relationship of the PAX7 promoter variants and livestock phenotypic traits has not been fully elucidated. We detected a novel 10-bp insertion/deletion (indel) polymorphism in the bovine PAX7 promoter and revealed that the indel altered the binding of the transcriptional factor ZNF219. Luciferase reporter assay showed that deletion-deletion (Del-Del) genotype of the PAX7 gene showed 2.79-fold higher promoter activity than the insertion-insertion (Ins-Ins) genotype (P < 0.05), and ZNF219 overexpression significantly diminished the luciferase activity in Ins-Ins groups. Moreover, the expression of PAX7 and its down-stream genes were detected in fetal skeletal muscle of cattle with different PAX7 genotypes, where the Del-Del genotype also displayed high expression levels. Statistical association analysis demonstrated that this indel had significant effects on early growth traits in cattle. These findings provide a complete overview of the function of the PAX7 10-bp variant, which may have potential as a genetic marker for marker-assisted selection in improving economically significant traits of cattle.

The ontogeny of the female reproductive system in the parasitic castrator pea crab Calyptraeotheres garthi: Implications for its mating system.

The knowledge of the mating system of pea crabs is still fragmentary as it remains dubious whether females copulate in the juvenile and free-living 'hard' or in the obligatory symbiotic stages (adult stage 'V' or intermediate stages II to IV). To discriminate between these two possibilities, we analysed the female seminal receptacles, vagina and opercula, and the sperm content in different stages of the pea crab Calyptraeotheres garthi. Our histology and scanning electron microscopy results revealed that in the hard stage the seminal receptacle is simple without secretory epithelia, and vagina and opercula are not controlled by musculature. In stages II to IV, the seminal receptacles, vagina, and opercula are under development and these structures reach maturity in stage V. These results suggest that females become receptive in stage V and not during predating stages. We found no spermatozoa in SR of 'hard' and stage II to IV females while these structures were loaded of sperm in most stage V, indicating that females start to mate in stage V. Our results support the notion that males of C. garthi roam among hosts in search for sedentary stage V females, as predicted by Baeza and Thiel's () model of mating systems for symbiotic crustaceans. Nevertheless, we failed to reveal whether females mate repeatedly: the accumulation of sperm in larger females might indicate occurrence of multiple copula or a high variability in male sperm transfer.

A comprehensive phylogeny of the genus Kurixalus (Rhacophoridae, Anura) sheds light on the geographical range evolution of frilled swamp treefrogs.

Currently, the genus Kurixalus comprises 14 species distributed in Southern, Southeast and East Asia. Because of their relatively low dispersal capability and intolerance of seawater, this group is ideal for the study of terrestrial range evolution, especially that portion of its range that extends into the island archipelagos of Southern Asia. We assembled a large dataset of mitochondrial and nuclear genes, and estimated phylogeny by maximum likelihood and Bayesian methods, and we explored the history of each species via divergence-time estimation based on fossil-calibrations. A variety of ancestral-area reconstruction strategies were employed to estimate past changes of the species' geographical range, and to evaluate the impact of different abiotic barriers on range evolution. We found that frilled swamp treefrogs probably originated in Taiwan or South Vietnam in the Oligocene. Alternatively, the lineage leading to Kurixalus appendiculatus strongly supports a hypothesis of terrestrial connection between the Indian and Asian continents in the Oligocene. The outcome of both our divergence-time estimates and ancestral-area reconstruction suggests that the divergence between species from Indochina and Taiwan can probably be attributed to the opening of the South China Sea, approximately 33 million years ago. We could not find evidence for dispersal between mainland China and Taiwan Island. Formation of both Mekong and Red River valleys did not have any impact on Kurixalus species diversification. However, coincidence in timing of climate change and availability of plausible dispersal routes from the Oligocene to the middle Miocene, plausibly implied that Kurixalus diversification in Asia resulted from contemporaneous, climate-induced environmental upheaval (Late Oligocene Warming at 29 Ma; Mi-1 glaciation since 24.4-21.5 Ma; Mid-Miocene Climatic Optimum at 14 Ma), which alternatively opened and closed dispersal routes.

How weather instead of urbanity measures affects song trait variability in three European passerine bird species.

Previous studies detected an influence of urban characteristics on song traits in passerine birds, that is, song adjustments to ambient noise in urban areas. Several studies already described the effect of weather conditions on the behavior of birds, but not the effect on song traits. We investigate, if song trait variability changes along a continuous urbanity gradient in Frankfurt am Main, Germany. We examined, for the first time on a larger scale, the influence of weather on song parameters. We made song recordings of three common passerine species: the blue and great tit (Cyanistes caeruleus (Linnaeus, 1758) and Parus major Linnaeus, 1758) and the European blackbird (Turdus merula Linnaeus, 1758). We measured different song traits and performed statistical analyses and modeling on a variety of variables-among them urbanity and weather parameters. Remarkably, we found only few cases of a significant influence of urbanity parameters on song traits. The influence of weather parameters (air pressure, atmospheric humidity, air and soil temperatures) on song traits was highly significant. Birds in Frankfurt face high noise pollution and might show different adaptations to high noise levels. The song trait variability of the investigated species is affected more by weather conditions than by urban characteristics in Frankfurt. However, the three species react differently to specific weather parameters. Smaller species seem to be more affected by weather than larger species.

Shared and unique patterns of phenotypic diversification along a stream gradient in two congeneric species.

Stream ecosystems show gradual variation of various selection factors, which can result in a zonation of species distributions and gradient evolution of morphological and life-history traits within species. Identifying the selective agents underlying such phenotypic evolution is challenging as different species could show shared and/or unique (species-specific) responses to components of the river gradient. We studied a stream gradient inhabited by two mosquitofishes (genus Gambusia) in the Río Grijalva basin in southern Mexico and found a patchy distribution pattern of both congeners along a stretch of 100 km, whereby one species was usually dominant at a given site. We uncovered both shared and unique patterns of diversification: some components of the stream gradient, including differences in piscine predation pressure, drove shared patterns of phenotypic divergence, especially in females. Other components of the gradient, particularly abiotic factors (max. annual temperature and temperature range) resulted in unique patterns of divergence, especially in males. Our study highlights the complexity of selective regimes in stream ecosystems. It exemplifies that even closely related, congeneric species can respond in unique ways to the same components of the river gradient and shows how both sexes can exhibit quite different patterns of divergence in multivariate phenotypic character suites.

Biotic interchange between the Indian subcontinent and mainland Asia through time.

Biotic interchange after the connection of previously independently evolving floras and faunas is thought to be one of the key factors that shaped global biodiversity as we see it today. However, it was not known how biotic interchange develops over longer time periods of several million years following the secondary contact of different biotas. Here we present a novel method to investigate the temporal dynamics of biotic interchange based on a phylogeographical meta-analysis by calculating the maximal number of observed dispersal events per million years given the temporal uncertainty of the underlying time-calibrated phylogenies. We show that biotic influx from mainland Asia onto the Indian subcontinent after Eocene continental collision was not a uniform process, but was subject to periods of acceleration, stagnancy and decrease. We discuss potential palaeoenvironmental causes for this fluctuation.

Data on phylogenetic analyses of gazelles (genus Gazella) based on mitochondrial and nuclear intron markers.

The data provided is related to the article "Phylogenetic analyses of gazelles reveal repeated transitions of key ecological traits and provide novel insights into the origin of the genus Gazella" [1]. The data is based on 48 tissue samples of all nine extant species of the genus Gazella, namely Gazella gazella, Gazella arabica, Gazella bennettii, Gazella cuvieri, Gazella dorcas, Gazella leptoceros, Gazella marica, Gazella spekei, and Gazella subgutturosa and four related taxa (Saiga tatarica, Antidorcas marsupialis, Antilope cervicapra and Eudorcas rufifrons). It comprises alignments of sequences of a cytochrome b data set and of six nuclear intron markers. For the latter new primers were designed based on cattle and sheep genomes. Based on these alignments phylogenetic trees were inferred using Bayesian Inference and Maximum Likelihood methods. Furthermore, ancestral character states (inferred with BayesTraits 1.0) and ancestral ranges based on a Dispersal-Extinction-Cladogenesis model were estimated and results׳ files were stored within this article.

Phylogenetic analyses of gazelles reveal repeated transitions of key ecological traits and provide novel insights into the origin of the genus Gazella.

African bovids are a famous example of a taxonomic group in which the correlated evolution of body size, feeding mode, gregariousness, and social organization in relation to the preferred habitat type has been investigated. A continuum has been described ranging from small-bodied, sedentary, solitary or socially monogamous, forest- or bush-dwelling, browsing species that seek shelter from predation in dense vegetation, to large-bodied, migratory, highly gregarious, grazing taxa inhabiting open savannahs and relying on flight or group-defense behaviors when facing predators. Here, we examined a geographically widespread clade within the Bovidae (the genus Gazella) that shows minimal interspecific variation in body size and asked if we could still uncover correlated changes of key ecological and behavioral traits during repeated transitions from open-land to mountain-dwelling. Our study used a multi-locus phylogeny (based on sequence variation of Cytb and six nuclear intron markers) of all extant members of the genus Gazella to infer evolutionary patterns of key ecological and behavioral traits and to estimate ancestral character states using Bayesian inference. At the base of the Gazella-phylogeny, open plains were inferred as the most likely habitat type, and three independent transitions toward mountain-dwelling were uncovered. Those shifts coincided with shifts from migratory to sedentary lifestyles. Character estimation for group size was largely congruent with movement patterns in that species forming large groups tended to be migratory, while small group size was correlated with a sedentary lifestyle. Evolutionary patterns of two other conspicuous traits (twinning ability vs. exclusive singleton births and hornless vs. horned females) did not follow this trend in the Gazella-phylogeny. Furthermore, we inferred the genus Gazella to have emerged in the Late Miocene to Pliocene (10-3Mya), and estimating ancestral ranges based on a Dispersal-Extinction-Cladogenesis model found the Middle East to be the most likely origin of the genus.

Unmasking alpha diversity, cladogenesis and biogeographical patterning in an ancient panarthropod lineage (Onychophora: Peripatopsidae: Opisthopatus cinctipes) with the description of five novel species.

Speciation and biogeographical patterning in the velvet worm Opisthopatus cinctipes was examined under a null hypothesis that numerous discrete lineages are nested within the species. A total of 184 O. cinctipes specimens, together with a single specimen of each of the two congeneric point endemic sister species (O. roseus and O. herbertorum), were collected throughout the forest archipelago in the Eastern Cape, KwaZulu-Natal and Mpumalanga provinces of South Africa. All specimens were sequenced for two partial mitochondrial DNA loci (COI and 12S rRNA), while a single specimen from each locality was sequenced for the nuclear 18S rRNA locus. Evolutionary relationships were assessed using maximum-likelihood and Bayesian inferences, while divergence time estimations were conducted using BEAST. A Bayesian species delimitation approach was undertaken to explore the number of possible novel lineages nested within Opisthopatus, while population genetic structure was examined for the COI locus using ARLEQUIN. Phylogenetic results revealed that O. cinctipes is a species complex comprising seven geographically discrete and statistically well-supported clades. An independent statistical approach to species delimitations circumscribed ca. 67 species. Results from divergence time estimation and rate constancy tests revealed near constant net diversification occurring throughout the Eocene and Oligocene with subdivision of ranges during the Miocene. Gross morphological characters such as leg pair number within O. cinctipes were invariant, while dorsal and ventral integument colour was highly polymorphic. However, scanning electron microscopy revealed considerable differences both between and within clades. The caveats associated with both morphological and algorithmic delineation of species boundaries are discussed. The five novel Opisthopatus species are described.

Amphibians crossing the Bering Land Bridge: evidence from holarctic treefrogs (Hyla, Hylidae, Anura).

Based on an updated, time-calibrated phylogeny and applying biogeographical model testing and diversification analysis, we re-examined systematics and biogeography of the Holarctic treefrog genus Hyla with a focus on the East Asian species. We analyzed four mitochondrial genes (12S and 16S rRNA, tRNA(Leu), ND1) and one nuclear gene (POMC) for 192 samples representing 30 species of Hyla. Based on our results we suggest that H. ussuriensis is a synonym of H. japonica. Specimens from Sakhalin and Kunashir Islands might represent a cryptic species within H. japonica. We confirm earlier hypotheses that the genus Hyla originated during the Eocene to Early Oligocene and that Eurasian species originated from two independent dispersal events from North America via the Bering Land Bridge. Middle Eocene to Oligocene dispersal gave rise to the most recent common ancestor of the West Palearctic H. arborea-group and the East Palearctic, newly defined, H. chinensis-group. The Northeast Asian H. japonica-group resulted from a second wave of colonization from the Nearctic. A trans-Atlantic dispersal route could be excluded. Dispersal of the H. arborea-group to the western Palearctic coincides with the closure of the Turgai Strait at the end of the Oligocene. Diversification of Hyla decreased at the end of the Middle Miocene, possibly coinciding with the end of the Mid Miocene Climatic Optimum and the advent of cooler and drier climates in the Northern Hemisphere.

Multilocus Phylogeny of the Afrotropical Freshwater Crab Fauna Reveals Historical Drainage Connectivity and Transoceanic Dispersal Since the Eocene.

Phylogenetic reconstruction, divergence time estimations and ancestral range estimation were undertaken for 66% of the Afrotropical freshwater crab fauna (Potamonautidae) based on four partial DNA loci (12S rRNA, 16S rRNA, cytochrome oxidase one [COI], and histone 3). The present study represents the most comprehensive taxonomic sampling of any freshwater crab family globally, and explores the impact of paleodrainage interconnectivity on cladogenesis among freshwater crabs. Phylogenetic analyses of the total evidence data using maximum-likelihood (ML), maximum parsimony (MP), and Bayesian inference (BI) produced a robust statistically well-supported tree topology that reaffirmed the monophyly of the Afrotropical freshwater crab fauna. The estimated divergence times suggest that the Afrotropical Potamonautidae diverged during the Eocene. Cladogenesis within and among several genera occurred predominantly during the Miocene, which was associated with major tectonic and climatic ameliorations throughout the region. Paleodrainage connectivity was observed with specimens from the Nilo-Sudan and East African coast proving to be sister to specimens from the Upper Guinea Forests in West Africa. In addition, we observed strong sister taxon affinity between specimens from East Africa and the Congo basin, including specimens from Lake Tanganyika, while the southern African fauna was retrieved as sister to the Angolan taxa. Within the East African clade we observed two independent transoceanic dispersal events, one to the Seychelles Archipelago and a second to Madagascar, while we observe a single transoceanic dispersal event from West Africa to São Tomé. The ancestral area estimation suggested a West African/East African ancestral range for the family with multiple dispersal events between southern Africa and East Africa, and between East Africa and Central Africa The taxonomic implications of our results are discussed in light of the widespread paraphyly evident among a number of genera.