Data from: The role of climatic and geological events in generating diversity in Ethiopian grass frogs (genus Ptychadena)

Ethiopia is a world biodiversity hotspot and harbors levels of biotic endemism unmatched in the Horn of Africa, largely due to topographic—and thus habitat—complexity, which results from a very active geological and climatic history. Among Ethiopian vertebrate fauna, amphibians harbor the highest levels of endemism, making amphibians a compelling system for the exploration of the impacts of Ethiopia’s complex abiotic history on biotic diversification. Grass frogs of the genus Ptychadena are notably diverse in Ethiopia, where they have undergone an evolutionary radiation. We used molecular data and expanded taxon sampling to test for cryptic diversity and to explore diversification patterns in both the highland radiation and two widespread lowland Ptychadena. Species delimitation results support the presence of nine highland species and four lowland species in our dataset, and divergence dating suggests that both geologic events and climatic fluctuations played a complex and confounded role in the diversification of Ptychadena in Ethiopia. We rectify the taxonomy of the endemic P. neumani species complex, elevating one formally synonymized name and describing three novel taxa. Finally, we describe two novel lowland Ptychadena species that occur in Ethiopia and may be more broadly distributed.

埃塞俄比亚是全球生物多样性热点地区，其生物特有性水平在非洲之角地区无出其右，这在很大程度上源于活跃的地质与气候历史所造就的地形乃至生境复杂性。在埃塞俄比亚的脊椎动物区系中，两栖类拥有最高的特有性水平，这使得两栖类成为探究埃塞俄比亚复杂非生物历史对生物多样化影响的理想研究体系。褶蛙属（Ptychadena）的草蛙在埃塞俄比亚物种多样性尤为突出，并在此类群中经历了进化辐射。本研究利用分子数据与扩展的类群采样策略，对高原进化辐射类群以及两个广泛分布的低地褶蛙属类群的隐存多样性进行检测，并探究其多样化模式。物种界定结果显示，本数据集涵盖9个高原物种与4个低地物种；分化时间定年结果表明，地质事件与气候波动共同在埃塞俄比亚褶蛙属类群的多样化进程中产生了复杂且相互交织的影响。我们对特有种纽曼褶蛙（Ptychadena neumani）物种复合体的分类学进行了修订，恢复了1个曾被正式异名的学名，并描述了3个新类群。最后，本研究描述了2个分布于埃塞俄比亚的低地褶蛙新物种，这类群可能拥有更广的分布范围。