Granite boulders act as deep‐time climate refugia: A Miocene divergent clade of rupicolous Cnemaspis Strauch, 1887 (Squamata: Gekkonidae) from the Mysore Plateau, India, with descriptions of three new species

• Published in: Journal of zoological systematics and evolutionary research Vol. 58; no. 4; pp. 1234 - 1261
• Main Authors: Agarwal, Ishan, Thackeray, Tejas, Pal, Saunak, Khandekar, Akshay
• Format: Journal Article
• Language: English
• Published: Berlin Hindawi Limited 01.11.2020
• Subjects: Biodiversity; biogeography; Boulders; Congeners; Divergence; dwarf geckos; Eocene; Granite; Habitats; microrefugia; Miocene; New species; Paleocene; Refugia; systematics; tropics; Western Ghats; India
• ISSN: 0947-5745; 1439-0469
• DOI: 10.1111/jzs.12391

We describe a divergent clade and three new rupicolous species of dwarf geckos of the genus Cnemaspis from the Mysore Plateau, southern India. Cnemaspis bangarasp. nov., C. graniticola sp. nov., and C.yelagiriensis sp. nov. differ from each other by 9%–18% uncorrected ND2 sequence divergence and other South Asian Cnemaspis by 17%–33% and are morphologically distinguishable from all regional congeners and each other. The new species are known from only granite boulders in montane habitats (>1,000 m asl.), just 60–120 km straight‐line distance apart from each other. A fossil‐calibrated timetree and ancestral area reconstructions indicate South Asian Cnemaspis originated in Western Ghats forests with initial divergence in the Paleocene‐Eocene making it perhaps the oldest Indian squamate clade. Cnemaspis that occur in Peninsular India in the dry zone outside the Western Ghats form three independently derived clades that occur in significantly warmer and drier habitats than those in the Western Ghats. The discovery of a Miocene divergent clade from rocky hills on the southern edge of the Mysore Plateau reveals these habitats as novel, long‐term climate refugia. This adds to the body of work revealing ancient origins of taxa in the Indian dry zone and supports the Mysore Plateau as an important and overlooked hot spot of lizard biodiversity. South Asian Cnemaspis has a Paleocene–Eocene origin in Western Ghats forests. Discovery of a novel Miocene divergent clade and three new rupicolous species of dwarf geckos that are endemic to montane (>1,000 m asl.) granite boulder habitats. Rocky hills on southern edge of Mysore Plateau are novel, long‐term climate refugia. Adds to body of work revealing ancient origins of Indian dry zone taxa.