Phylogenetics and Integrative Taxonomy of African Water Snakes (Squamata: Colubridae: Grayia)

Grayia is a genus of relatively large (1.5 – 2.5 m) aquatic Afrotropical snakes that is currently comprised of four species. Recent molecular phylogenies recovered Grayia in its own distinct subfamily (Grayiinae), which was strongly supported as the sister group to Colubrinae. Because tropical African snakes are generally understudied, the relationships within Grayia are poorly known. Due to morphological conservatism, identification is often difficult and previous studies involving Grayia included misidentified specimens in other genera. The goal of this study is to build a phylogenetic tree that can be used to understand the relationships and taxonomy of Grayia via an integrative taxonomic approach that combines molecular and morphological data. One nuclear (BDNF) and four mitochondrial genes (COI, cyt b, 16S and ND4) were used to construct a phylogenetic tree with Maximum likelihood methods; outgroups included the genera Calamaria, Sibynophis and Masticophis. Preliminary trees suggest G. ornata and G. smithii are sister taxa, whereas G. caesar (originally described as the sole member of the genus Xenurophis) is sister to G. tholloni. At least two divergent lineages of G. ornata suggest cryptic species are likely present in Democratic Republic of the Congo (DRC) and Republic of Congo.

Peer Review, Abstract of an Oral Presentation or a Poster

Poster P93. 2021 Joint Meeting of Ichthyologists and Herpetologists, Phoenix, Arizona, 21-27 July 2021.