Wednesday, September 19, 2018

[Herpetology • 2018] Systematic Revision of Calotes Cuvier, 1817 (Squamata: Agamidae) from the Western Ghats adds Two Genera and Reveals Two New Species

Monilesaurus acanthocephalus &  M. montanus 
 Pal, Vijayakumar,  Shanker,  Jayarajan & Deepak, 2018

Lizards of the genus Calotes are geographically restricted to South Asia, Indo-China and parts of Southeast Asia. The greatest diversity of the genus is from the biodiversity hotspots in South Asia: Western Ghats (Peninsular India), Sri Lanka and Indo-Burma. Here, we present a systematic revision of members of the genus Calotes from Peninsular India using a combination of molecular phylogeny, geographical distribution and morphological characters. We show that Calotes from the Western Ghats is paraphyletic and consists of three major clades, one of which is widely distributed in South and Southeast (SE) Asia, while the others are restricted to Peninsular India. The Peninsular Indian clade is composed of two sister clades: Psammophilus, with a wider distribution and a second clade, composed of two extant species, Calotes rouxii and Calotes ellioti and two new species, all restricted to the Western Ghats region. Based on morphological differences, we retain the generic status of Psammophilus and assign its sister clade to a new genus Monilesaurus gen. nov. and transfer the following species, C. rouxii and C. ellioti, to this new genus. We also provide diagnoses and descriptions for two new species recognized within Monilesaurus gen. nov. In addition, Calotes aurantolabium from the Western Ghats was observed to be deeply divergent and to share a sister-relationship with the clade composed of CalotesMonilesaurus gen. nov., and Psammophilus. Based on its phylogenetic position and morphological attributes, we assign this species to a new genus Microauris gen. nov. These new discoveries highlight the evolutionary significance of the Western Ghats in housing novel lizard diversity.

Keywords: Reptilia, Agamidae, Calotes, new genus, MicroaurisMonilesaurusPsammophilus, Western Ghats

 Family Agamidae
Subfamily Draconinae  

Calotes Cuvier, 1817
Lacerta calotes Linnaeus, 1758 

Four species of Calotes (Calotes grandisquamis, C. nemoricola, Calotes cf. versicolor, Calotes calotes) are known from the Western Ghats of which two are endemic to this region.

Calotes nemoricola Jerdon, 1853 

Calotes grandisquamis Guenther, 1875

Calotes versicolor group

Content. Calotes bachae Hartmann, Geissler, Poyarkov, Ihlow, Galoyan, Rödder & Böhme, 2013C. bhutanensis Biswas, 1975; Ccalotes (Linnaeus, 1758)C. ceylonensis Müller, 1887; C. chincollium Vindum, 2003; C. desilvai Bahir & Maduwage, 2005; C. emmaC. grandisquamisC. hutunwini Zug & Vindum, 2006C. irawadi Zug, Grown, Schulte & Vindum, 2006Cjerdoni Günther, 1870; C. liocephalus Günther, 1872; C. liolepis Boulenger, 1885; C. versicolor (Daudin, 1802), Cmanamendrai Amarasinghe & Karunarathna, 2014C. maria Gray, 1845; C. medgoensis Zhao & Li, 1984Cminor, C. mystaceus Duméril & Bibron, 1837C. nemoricola Jerdon, 1853C. nigrilabris Peters, 1860; C. nigriplicatus Hallermann, 2000 and Cpethiyagodai Amarasinghe, Karunarathna, Hallermann, Fujinuma, Grillitsch & Campbell, 2014.

FIGURE 7. Lateral photograph showing live coloration of
 A. adult male Monilesaurus acanthocephalus gen. et sp. nov. and
. adult male
Monilesaurus montanus sp. nov. 

Monilesaurus gen. nov. 
Type species. Calotes rouxii (Duméril & Bibron, 1837)

 Content. Monilesaurus ellioti comb. nov., Monilesaurus montanus gen. et sp. nov., Monilesaurus rouxii comb. nov. and Monilesaurus acanthocephalus gen. et sp. nov.

Etymology. The genus epithet is derived by adding the word ‘Monile’ meaning necklace in Latin referring to the distinct neck fold in this genus and the Greek word sauros meaning lizard which is latinized here as saurus.

Monilesaurus rouxii (Duméril & Bibron, 1837) comb.nov. 
Calotes rouxii—Duméril & Bibron, 1837. Erp. Gen, iv, 1837: 407. 
Calotes ellioti—(not of Günther) Stoliczka, 1872. J. Asiat. Soc. Beng. (2) xli, 1872: 113. 
Calotes rouxii—Smith, 1935. Fauna of British India, ii, 1935: 206.

Monilesaurus ellioti (Günther, 1864) comb. nov. 
Calotes rouxii—(not of Dum. & Bibr., 1837), Jerdon, 1853. J. Asiat. Soc. Beng. (2) xxii, 1853: 471 
Calotes ellioti—Günther, 1864. Rept. Brit. Ind. 1864: 142. 
Bronchocela indica—Theobald, 1876. Cat. Rept. Brit. Ind. 1876: 105. 
Calotes elliotti—Smith, 1935. Fauna of British India, ii, 1935: 207.

Monilesaurus acanthocephalus gen. et. sp. nov. 
 Etymology. The species epithet is derived by combining the Greek word ‘acanthos’, meaning spine or thorn, and ‘kephale’ latinized as ‘cephalus’ meaning head; referring to the long posterorbital and supratympanic spines.

Monilesaurus montanus gen. et. sp. nov. 
 Etymology. The species epithet is derived from the word ‘montane’ referring to the restricted distribution of this species to high elevation forests (> 1500 m a.s.l).

Psammophilus Fitzinger, 1843
Type species: Agama dorsalis (Gray, 1845) 

Content: Psammophilus dorsalis, Psammophilus blanfordanus (Stoliczka, 1871)
Etymology: None provided but probably from Latin “Psammo” meaning sand and “Philus” meaning loving.

Psammophilus dorsalis (Gray, 1831) (Fig. 8a)
Agama dorsalis –Gray, 1831. In Griffith, E & E. Pidgeon’s Anim. King. ix, 1851: 56 
Charasia dorsalis– Gray, 1845. Cat. Liz. Brit. Mus. 1845: 246. 
Charasia dorsalis—Boulenger, 1885. Cat. Liz. Brit. Mus. 1845: 450. 
Psammophilus dorsalis—Smith, 1935. Fauna of British India, ii, 1935: 209. 

FIGURE 8. Lateral photograph showing live coloration of  adult female Microauris aurantolabium comb. nov.  

Microauris gen. nov.  
Type species. Calotes aurantolabium (Krishnan, 2008) 

Etymology. The genus epithet is derived by adding the word ‘Micro’ as a prefix to the Latin word ‘auris’ meaning ear, referring to the extremely small tympanum of this genus.

Suggested English. Small-eared dragon

Saunak Pal, S.P. Vijayakumar, Kartik Shanker, Aditi Jayarajan and V. Deepak. 2018. A Systematic Revision of Calotes Cuvier, 1817 (Squamata: Agamidae) from the Western Ghats adds Two Genera and Reveals Two New Species. Zootaxa. 4482(3); 401–450. DOI: 10.11646/zootaxa.4482.3.1