A molecular-genetics perspective on the systematics of the parthenogenetic flowerpot blindsnake Indotyphlops braminus (Daudin, 1803) (Squamata: Serpentes: Typhlopidae)

Abstract

Sri Lanka has a rich snake diversity, but the island’s scolecophidians (‘blindsnakes’) are poorly understood due to the cryptic, burrowing habits of these inconspicuous animals and lack of systematic field surveys and morphological and molecular analyses. Here we report findings from a systematic survey carried out over a decade across the island of Sri Lanka, focusing particularly on the globally widespread, parthenogenetic species Indotyphlops braminus. We report 780 locations across the island in which this species was recorded, at elevations of 1–1,424 m asl, and mostly <1,000 m (771 out of 780 localities). We provide a molecular-systematics perspective by reporting new DNA sequence data for 15 specimens from Sri Lanka, and new analyses of asiatyphlopine molecular genetic diversity and relationships. Based on molecular results, we conclude that (i) Indotyphlops, as originally conceived may not be monophyletic, (ii) phenotypically the I. braminus-like blindsnakes widespread across most of Sri Lanka are a single, genetically homogeneous species, and (iii) some populations from peninsular India are very similar in DNA sequence to I. braminus from Sri Lanka, but others are genetically highly distinct and unlikely to be conspecific. Based on the estimated phylogenetic relationships, we recommend that I. braminus is currently best recognized as a phenotypically exceptional species of Indotyphlops rather than, as recently proposed, the only species of a monotypic genus (Virgotyphlops).

Key words:

• Asiatyphlopinae
• distribution
• diversity
• phylogenetics
• snake
• Sri Lanka
• Typhlopidae

Acknowledgements

Fieldwork was undertaken with permission from the Department of Wildlife Conservation (Permit no: WL/3/2/2/13) and the Forest department (Permit No: R&E/RES/NFSRCM/2018-02), which we gratefully acknowledge. Equipment and enabling of museum reference work outside Sri Lanka was funded by Nagao Natural Environment Foundation, Japan and Dilmah Conservation, Sri Lanka. The Commercial Bank PLC, Sri Lanka and the Bird and wildlife team funded the molecular studies. The Global Environment Facility of the United Nations Development Project (UNDP), and Wildlife and Nature Protection Society provided partial funds for molecular studies and fieldwork. Van Wallach and Addison Wynn kindly provided important reference material relevant to the current study as well as commenting on the submitted manuscript. We thank Dinarzarde Raheem, Rohan Pethiyagoda and an anonymous reviewer for additional constructive comments. Dushantha Wasala, H. C. Nasrullah, Gehan Rajeev, Aravinda Boomi, Kithmini Wickramarachchi, and Chamara Amarasinghe assisted fieldwork. Prasanna Samarawickrama prepared the distribution map, and Mahesh Chathuranga prepared Fig. 2. NW would like to thank Filipa Sampaio and Kanishka Ukuwela for technical mentorship. NW and LJMW thank colleagues from the Herpetological Foundation of Sri Lanka, and the Institute of Biochemistry, Molecular Biology, and Biotechnology of the University of Colombo for various courtesies.

Disclosure statement

No potential conflict of interest was reported by the authors.

Supplemental Material

Supplemental material for this article can be accessed here: https://doi.org/10.1080/14772000.2022.2062478.

Associate Editor: Dr Susan Tsang

Additional information

Funding

This work was supported by the [Nagao Natural Environment Foundation, Japan]; the [Dilmah Conservation, Sri Lanka]; the [Commercial Bank PLC, Sri Lanka]; the [Global Environment Facility of the United Nations Development Project (UNDP)] under Grant [number SRL/SGP/OP6/STAR/BD/2018/09]; the [Bird and wildlife team] and the [Wildlife and Nature Protection Society, Sri Lanka].