Friday, January 26, 2024

[Herpetology • 2024] Agasthyagama edge • A New Species of Kangaroo Lizard (Squamata: Agamidae: Agasthyagama) from the southern Western Ghats of India


Agasthyagama edge
 Das, Pal, Narayanan, Subin, Palot, Rajkumar, & Deepak, 2024

Northern Kangaroo Lizard | വടകൻ കംഗാരു ഒാന്ത്  ||  DOI: 10.3897/vz.74.e113084 

Abstract
We describe a new species of Agasthyagama from Idukki district, Kerala, India. The new species is distinguished from its sister species Agasthyagama beddomii by a combination of scale characters and are also genetically different from each other with 11% uncorrected pairwise difference in ND2 gene and 3% in 16S gene. The two species are also geographically separated, the closest distributional records are approximately 80 km apart.

Keywords: Agamid, endemic, evergreen forest, Kerala, southern India, Tamil Nadu, terrestrial

Agasthyagama edge sp. nov. in life:
 A uncollected adult male from Kulamavu, Idukki; B uncollected female from the same locality.
Photographs by Sandeep Das.



Agasthyagama edge sp. nov.

Comment: There are no previous records of Agasthyagama from the mountains in Idukki district. Sivagiri hills according to a map provided by Smith (1935) is on the Eastern slopes of the Western Ghats immediately north of the Shencotta/ Shencottah gap.

Diagnosis and comparison: 
A small-sized agamid (SVL 30–42.5 mm; n = 11) lizard characterised by the presence of heterogenous dorsolateral scales, oriented backwards, small overlapping scales with larger often trihedral scales; larger scales roughly forming 5 or 6 chevron shaped ridges on mid dorsum from nuchal region to above cloaca; strongly keeled enlarged scales randomly scattered laterally, 76–82 rows of scales around midbody; head with unequal keeled scales, supraciliary edge sharp; a small antehumeral pit present, tympanum concealed; nuchal and dorsal crests absent; ventral scales strongly keeled, larger than lateral scales, 73–80 ventrals from mentum to cloaca; gular scales at the mid-line nearly equal to the adjacent scales; males with a small dewlap, 32–35 scales from mentum to last dewlap scale; limbs slender, covered with larger keeled scales; 4th digit on pes much longer than others, 5th digit on pes much reduced. Uniform olive-brown body, with lighter, enlarged scales laterally, mid dorsum paler; breeding males with pale peach to grey mid dorsum; dewlap in breeding males with pale bluish-white centre flanked by reddish-brown stripe.
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Etymology: The species is named after the Zoological Society of London’s EDGE of Existence Program who supported SD and RKP, and several early career conservation researchers across the globe in their projects on evolutionarily distinct species. EDGE is an acronym for Evolutionarily Distinct and Globally Endangered. The specific epithet “edge” is a patronym as a noun in apposition. We suggest common name “Northern Kangaroo Lizard” and വടകൻ കംഗാരു ഒാന്ത് (vadakan kangaroo oanth) as a regional Malayalam name.


Agasthyagama beddomii in life, all uncollected individuals from various localities: 
A adult male from Kanayar, Achankovil; 
D female from Rockwood, Shendurney Wildlife Sanctuary; 
F female from Arippa, Trivandrum. 
Agasthyagama edge sp. nov. in life:
A uncollected adult male from Kulamavu, Idukki; 
B uncollected female from the same locality.
Photographs by Sandeep Das


 Sandeep Das, Saunak Pal, Surya Narayanan, K. Subin, Muhamed Jafer Palot, K. P. Rajkumar, V. Deepak. 2024.  Discovery of A New Species of Kangaroo Lizard (Squamata: Agamidae: Agasthyagama) from the southern Western Ghats of India. Vertebrate Zoology. 74: 151-168. DOI: 10.3897/vz.74.e113084