African Vine Snakes of the genus Thelotornis are highly specialised arboreal colubrids distributed across sub‐Saharan Africa. Despite pronounced morphological conservatism, the genus occupies diverse forest, woodland and savanna‐associated habitats. The genus has long been characterised by unresolved species boundaries and taxonomic uncertainty, particularly regarding the placement of the monotypic Xyelodontophis uluguruensis . We investigated phylogenetic relationships and species boundaries within Thelotornis using an integrative framework with broad geographic and ecological sampling. Phylogenetic inference was based on two mitochondrial (cyt b and ND4) and two nuclear (c‐mos and NT3) markers analysed under maximum‐likelihood (IQ‐TREE2) and multispecies coalescent (Species Tree And Classification Estimation, Yarely STACEY) frameworks. Species boundaries were further assessed using haplotype networks, mitochondrial divergence, single‐locus barcoding (Assemble Species by Automatic Partitioning ASAP) and unsupervised machine learning (UML) clustering (super self‐organising map SuperSOM) integrating genetic, morphological, ecological and spatial data. Seven independently evolving lineages are supported, with Thelotornis monophyletic only when Xyelodontophis uluguruensis is included. Thelotornis capensis subspecies are recognised as distinct species, and an undescribed lineage from Vamizi Island, Mozambique, has been identified. Emergence of the genus trace to the Mid‐Miocene ( ca . 16.6 Mya), with Late‐Miocene diversification giving rise to a West–East African forest lineage ( T. kirtlandii and T. uluguruensis comb. nov.) and an East–Southern African lineage comprising habitat generalists ( T. usambaricus , T . sp., T. mossambicanus and T. capensis ) alongside the savanna specialist T. oatesi stat. nov. Morphological, ecological and genetic evidence support the distinctiveness of all seven lineages, informing a revised diagnosis of Thelotornis . These results indicate a recent ecological radiation shaped by historical habitat dynamics, facilitating forest niche conservatism while ecological opportunity enabled savanna diversification, resolving taxonomic ambiguity and revealing hidden diversity.
Engelbrecht et al. (Thu,) studied this question.