Authors: Bivek Gautam, Santosh Bhattarai, Bishal Prasad Neupane, Chiranjibi Prasad Pokheral, Tejas Thackeray, Akashay Khandekar, Vivek Phillip Cyriac, Ishan Agarwal
Abstract: A new species of ground-dwelling gecko of the genus Cyrtodactylus (Geckoella) is described
from the low elevation Terai-Duar region of southeastern Nepal using molecular
and morphological data. Cyrtodactylus teraiensis sp. nov. is the first new species of
the C. nebulosus species complex, the remaining members of which are distributed
in the northern Eastern Ghats and Satpuras; a lectoype for C. nebulosus is also designated.
The new species is the first Geckoella described from outside peninsular India
and distributed north of the Indo-Gangetic Plains. Cyrtodactylus teraiensis sp. nov.
forms the deeply divergent sister taxon to Indian members of the C. nebulosus complex
with 15.7–18.1% uncorrected mitochondrial sequence divergence from them, and
21.0–28.5% from other Geckoella. The new species is also recognised in tree-based delimitation
methods and can be morphologically distinguished from other Cyrtodactylus
and Geckoella species by a small body size (snout to vent length, SVL up to at least
45.5 mm), length of original tail < SVL, 16–18 rows of dorsal tubercles, 30–32 ventral
scales across belly at midbody; dorsal colour pattern of four or five paired spots between
neck and hindlimb insertions alternating with two or three much smaller paired
spots. The divergence between Cyrtodactylus teraiensis sp. nov. and Indian members
of the C. nebulosus complex is estimated to have occurred in the Middle Miocene, and
it may be that tropical forest expansion during the Mid-Miocene Climatic Optimum allowed
dispersal across the Indo-Gangetic Plains.
Keywords: Endemic species, Indian subcontinent, integrative taxonomy, mitochondrial
DNA, taxonomy
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