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GrayiaGünther 1858 is a genus of relatively large (1.2–2.5 m) aquatic Afrotropical snakes. Recent molecular phylogenies recovered Grayia in its own distinct subfamily (Grayiinae), which was supported as the sister group to Colubrinae. Tropical African snakes are generally understudied, so the relationships within Grayia are poorly known. High degrees of intra- and interspecies variation can make identification difficult, and previous studies involving Grayia included misidentified specimens in other genera. The goal of this study is to create a phylogenetic tree that can be used to understand the relationships and taxonomy of Grayia via an integrative taxonomic approach that combines molecular data for 60 specimens and morphological data for 719 specimens. Two nuclear (BDNF, NT3) and four mitochondrial genes (COI, cyt b, 16S, and ND4) were used to construct phylogenetic trees with Maximum Likelihood and Bayesian Inference algorithms. The phylogenetic trees recovered two clades, Grayia caesar + G. tholloni and G. ornata + G. smythii, which the time-calibrated Bayesian Evolutionary Analysis Sampling Tree (BEAST) analysis estimated to have diverged from each other in the mid-Oligocene. This deep divergence, combined with distinct morphological differences, led us to resurrect the name XenurophisGünther 1863 as a subgenus [G. (Xenurophis) caesar, G. (Xenurophis) tholloni]. Molecular and morphological evidence further supports a new cryptic species of Grayia from the Upper and Middle Congo River and its tributaries. This new species is estimated to have diverged from its nearest sister species, G. ornata, in the Late Miocene—which coincides with the divergence dates of sister taxa within other Central African snake genera. Grayia ornata sensu stricto was found to consist of several evolutionary lineages, which mirror the patterns recovered in other Central African vertebrates. [ABSTRACT FROM AUTHOR]

The chelonian fauna of Togo (West Africa) has been scarcely studied to date. In this article, we review and summarize all available data on the distribution, ecology, and conservation status of the chelonian species of Togo and present a short historical perspective on the development of studies on these reptiles. Overall, 13 chelonian species are found in Togo, 4 being marine, 3 terrestrial, and 6 freshwater. Among the marine species, only 2 of them nest on Togolese beaches ( Lepidochelys olivacea and Dermochelys coriacea). Two species ( Chelonia mydas and L. olivacea) are still locally common. Concerning the terrestrial and freshwater species, they differed remarkably in terms of their distribution by ecological zone. Cluster analyses revealed the existence of 3 clusters of species, 1 that contains the 'forest' species, 1 accommodating the Sudanese savannah species, and a third cluster for the generalist savannah species. The conservation status of the various species and their dissimilarities in terms of threat score categories were assessed through a multivariate model following published work on African chelonian species in general. The results of this model indicate that the potentially most threatened species in Togo are Kinixys erosa, Kinixys homeana, and the 2 Cyclanorbis species ( C. senegalensis and C. elegans), with Trionyx triunguis also being possibly seriously threatened. Overall, using the International Union for Conservation of Nature Red List criteria, the concurrent presence of 2 Critically Endangered ( K. homeana, C. elegans), 1 Endangered ( K. erosa), and several Vulnerable species shows that the chelonian fauna of Togo should be of priority relevance for the competent international agencies. [ABSTRACT FROM AUTHOR]