Description of two new species of Cnemaspis Strauch, 1887 (Squamata: Gekkonidae) from the Western Ghats of Kerala, India

Abstract

Two new species of geckos of the genus Cnemaspis Strauch, 1887 are described from the southern Western Ghats of Kerala. Both species are medium to large sized Cnemaspis and can be differentiated from all other Indian congeners by a suite of distinct morphological characters. Both species are found in the high elevation forests of the two major massifs— Anaimalai Hills and Agasthyamalai Hills and are presently known to have very restricted distributional ranges. The discovery of these novel species highlights the understudied diversity of reptiles in the high mountain ranges of the Western Ghats.

Diversifying on the Ark: multiple new endemic lineages of dwarf geckos from the Western Ghats provide insights into the systematics and biogeography of South Asian <i>Cnemaspis</i> (Reptilia: Squamata)

“…Several recent studies have explored the phylogenetic relationships within SA Cnemaspis ( Agarwal et al, 2017 , Cyriac et al, 2018 , 2020 , Khandekar et al, 2019a , 2019b ) as well as the evolutionary origin of lineages within the group ( Agarwal et al, 2020b ). However, these previous studies did not adequately sample the WG, where the genus is most diverse.…”

“…In total, 240 Cnemaspis individuals were examined for morphological analyses, including type specimens of the new lineages described herein as well as extant species from Peninsular India, topotypical specimens, type specimens, and other museum specimens listed in the material examined section (Appendix II). Comparative data on the described Cnemaspis species from Peninsular India were also taken from published literature ( Agarwal et al, 2020b ; Cyriac & Umesh, 2013 , 2014 ; Cyriac et al, 2018 , 2019 , 2020 ; Das & Bauer, 2000 ; Giri et al, 2009a , 2009b ; Khandekar, 2019 ; Khandekar et al, 2019a , 2019b , 2020b ; Manamendra-Arachchi et al, 2007 ; Mirza et al, 2014 ; Mukherjee et al, 2005 ; Murthy et al, 2019 ; Sayyed et al, 2016 , 2018 , 2019 , 2020 ; Srinivasulu et al, 2015 ). Counts and external observations of morphology and meristic characters were made under a Leica stereo dissecting microscope, and on the left side of the body for symmetrical characters where possible.…”

“…Due to the presence of a circular eye pupil, Cnemaspis geckos are often thought to be diurnal and are commonly called “day geckos”, although studies report that at least some are nocturnal ( Grismer et al, 2014 ) and/or crepuscular. Similar to other endemic fauna of the WG, most Cnemaspis geckos have limited distribution ranges and microhabitats ( Agarwal et al, 2020a ; Chaitanya et al, 2019 ; Cyriac et al, 2018 , 2019 ), and many are known only from the type locality and museum specimens ( Manamendra-Arachchi et al, 2007 ; Murthy et al, 2019 ). It is important to assess and validate the status of these species by locating extant populations, and to address taxonomic uncertainties and systematic relationships.…”

“…The diverse SA clade of Cnemaspis comprises some 85 known species with disjunct distributions across Peninsular India and Sri Lanka, as well as Myanmar, northeast India, and islands west of Sumatra ( Agarwal et al, 2017 ; Grismer et al, 2014 ; Khandekar et al, 2020a ; Lee et al, 2019 ; Uetz et al, 2020 ). In the past two decades, there has been a rapid increase in the discovery of new species of SA Cnemaspis in both Sri Lanka and India, primarily due to extensive taxonomic revisions and the use of molecular phylogenies to delimit species ( Cyriac et al, 2018 , 2020 ; Karunarathna et al, 2019a , 2019b ; Khandekar et al, 2019a ; Manamendra-Arachchi et al, 2007 ; Sayyed et al, 2018 ). Neverthless, the diversity of SA Cnemaspis is likely to be greatly underestimated.…”

Elevational gradients of reptile richness in the southern Western Ghats of India: Evaluating spatial and bioclimatic drivers

“…Particularly, 47% of the reptiles that occur here are endemic to the Western Ghats (Srinivasulu et al., 2014). Recent studies have also indicated that each mountain range in the Western Ghats possibly has many local endemics and basal lineages—especially in case of reptiles (Chaitanya et al., 2019; Cyriac et al., 2018; Deepak et al., 2020; Mallik et al., 2019; Pal et al., 2018). Consequently, there is a need to better document and explain patterns of species richness in this region.…”