Centre for Ecological Sciences, Indian Institute of Science, Bangalore 560012, India.
Centre for Ecological Sciences, Indian Institute of Science, Bangalore 560012, India.
Mol Phylogenet Evol. 2021 Apr;157:107064. doi: 10.1016/j.ympev.2020.107064. Epub 2020 Dec 31.
The Indian subcontinent's unique geological history is reflected in the diverse assemblage of its biota. The blindsnake superfamily Typhlopoidea, with its unique mix of ancient as well as younger lineages in Asia, provides an opportunity to understand the various biotic exchange scenarios proposed for the Indian landmass. In this study, we aim to understand the biogeographic origins of the four genera of typhlopoids found in India and to decipher their times and modes of arrival in the subcontinent. Five nuclear markers were sequenced for 12 samples collected from across India, encompassing all four genera under study. Published sequences of typhlopoid genera were compiled and combined with Indian sequences to generate a global dataset. Phylogenetic relationships were reconstructed using maximum likelihood and Bayesian inference methods. Divergence times were estimated using BEAST 1.8.2. Ancestral geographical ranges were estimated using DEC + J, implemented in BioGeoBEARS. Divergence time estimates suggest that Gerrhopilus is an ancient lineage, and the lineage leading to it was present on the Indian landmass since the last 100 million years. The other three genera are more recent dispersals into India, possibly trans-oceanic. Biogeographic reconstructions suggest an East Gondwanan origin for Typhlopoidea, an African origin for Grypotyphlops and an Asian origin for Indotyphlops and Argyrophis. It appears that India harbours a combination of ancient and more recently dispersed lineages of typhlopoids. The genus Gerrhopilus is of Gondwanan origin that likely dispersed out of India into Southeast Asia. The other genera are intrusive elements that dispersed into India from Africa (Grypotyphlops) and Asia (Indotyphlops and possibly Argyrophis) post break-up of Gondwana. Thus, our study provides further evidence on the ability of blindsnakes to undergo long distance trans-oceanic dispersal. Results also suggest an Asian origin for typhlopoids from Australasia, Philippines and Wallacea.
印度次大陆独特的地质历史反映在其生物群的多样性组合中。盲蛇超科 Typhlopoidea 以其在亚洲独特的古老和年轻谱系混合为特色，为了解为印度次大陆提出的各种生物交换情景提供了机会。在这项研究中，我们旨在了解在印度发现的四种盲蛇属的生物地理起源，并破译它们到达次大陆的时间和方式。为了从印度各地收集的 12 个样本中测序五个核标记，涵盖了正在研究的四个属。编译了盲蛇属的已发表序列，并将其与印度序列结合，生成了一个全球数据集。使用最大似然和贝叶斯推断方法重建了系统发育关系。使用 BEAST 1.8.2 估计分歧时间。使用 DEC+J 在 BioGeoBEARS 中估计祖先地理范围。分歧时间估计表明，Gerrhopilus 是一个古老的谱系，其谱系自 1 亿年前以来就存在于印度次大陆上。其他三个属是最近进入印度的扩散，可能是跨洋的。生物地理重建表明 Typhlopoidea 的起源是东冈瓦纳，Grypotyphlops 的起源是非洲，Indotyphlops 和 Argyrophis 的起源是亚洲。似乎印度拥有古老和最近扩散的盲蛇谱系的组合。属 Gerrhopilus 起源于冈瓦纳，可能从印度扩散到东南亚。其他属是侵入性元素，从非洲（Grypotyphlops）和亚洲（Indotyphlops 并可能是 Argyrophis）扩散到印度，冈瓦纳分裂后。因此，我们的研究进一步证明了盲蛇能够进行长距离跨洋扩散。结果还表明，来自澳大拉西亚、菲律宾和华莱士区的盲蛇起源于亚洲。
