An integrated approach to the taxonomy of hipposiderid bats in South Asia

Abstract

Cryptic diversity has been well documented in several bat families and particularly in the Old-World families such as the Hipposideridae and Rhinolophidae which exhibit high levels of acoustic divergence. The genus Hipposideros is the most speciose in the family Hipposideridae and is well known for its taxonomic complexity due to the presence of several morphologically cryptic lineages. This study aims to unravel the
taxonomic uncertainty in two hipposiderids, Hipposideros pomona Andersen, 1918 and Hipposideros lankadiva Kelaart, 1850 from South Asia. H. pomona from southernIndia has recently been identified as a distinct species. Meanwhile, all specimens from northeast India and Southeast Asia have been assigned to H. gentilis Andersen, 1918. Currently, three subspecies are recognised in H. lankadiva: H. l. lankadiva (Sri Lanka), H. l. indus (peninsular India) and H. l. gyi (northeast India and Myanmar). To date, no study has reassessed the taxonomic status of these taxa using an integrated
taxonomic approach throughout their geographic extent. Therefore, an integrated taxonomic approach was applied using multiple lines of evidence, namely: morphometrics, bioacoustics and molecular phylogenetics. In addition, a presenceonly modelling approach (MaxEnt) was used to better understand the geographic distribution of the targeted taxa. Results showed that H. pomona is distinct from H. gentilis sensu lato based on morphometrics, bacular and molecular data and its distribution is confined to the south of peninsular India. Hence, the recent species status of H. pomona is valid. Although there is a significant variation in the size and echolocation call frequency of H. lankadiva from Sri Lanka and northeast India-Myanmar compared with bats from mainland India, the taxon exhibited moderate to low genetic divergence in both mitochondrial and nuclear datasets. Therefore, the current subspecies status is appropriate in H. lankadiva. Species distribution models predicted that H. pomona is restricted to southern areas in peninsular India, though
suitable conditions exist for its presence in Sri Lanka. The range of H. gentilis s.l. potentially overlaps with that of H. pomona in some areas of peninsular India. Models predicted that the three subspecies of H. lankadiva do not overlap in range.In conclusion, the present results reiterate the importance of using integrated approaches in bat taxonomy.

Date of Award	24 Mar 2020
Original language	English
Awarding Institution	University of Bristol
Supervisor	Gareth Jones (Supervisor)