Psammophilus dorsalis (GRAY, 1831)
Can you confirm these amateur observations of Psammophilus dorsalis?
|Higher Taxa||Agamidae (Draconinae), Sauria, Iguania, Squamata (lizards)|
|Common Names||South Indian Rock Agama, Peninsular Rock Agama|
|Synonym||Agama dorsalis GRAY in GRIFFITH & PIDGEON 1831: 56|
Agama dorsalis — DUMÉRIL & BIBRON 1837: 486
Charasia dorsalis — GRAY 1845
Charasia dorsalis — ANDERSON 1871: 151
Charasia dorsalis — BOULENGER 1885: 332
Psammophilus dorsalis — SMITH 1935: 309
Psammophilus dorsalis — WERMUTH 1967: 95
Psammophilus dorsalis — DAS 1996: 45
Psammophilus dorsalis — MURTHY 2010
Psammophilus cf. dorsalis — KARTHIK et al. 2018
|Distribution||S India (Malabar, Mysore, Nilgiris, S Arcot, Nallamali Hills, Bihar, Orissa, Madhya Pradesh, Karnataka, Andhra Pradesh, Karnataka, Kerala, Tamil Nadu)|
Type locality: India.
|Diagnosis||Diagnosis (genus). The genus Psammophilus can be distinguished from the genera Cophotis, Ceratophora, Lyriocephalus, Ptyctolaemus, Phoxophrys, Japalura otai Mahony 2009, J. planidorsata Jerdon, 1870, J. sagittifera Smith, 1940 and Otocryptis by the presence of an external tympanum (Boulenger, 1885; Smith, 1935; Inger, 1960; Pethiyagoda & Manamendra-Arachchi 1998; Schulte II et al. 2004; Bahir & Silva 2005; Manamendra-Arachchi et al. 2006; Samarawickrama et al. 2006); from other members of genus Japalura by the absence of heterogenous dorsal scales and short and thick nuchal scales.|
The genus Psammophilus can be diagnosed from all other species of draconinae lizards from the Indian subcontinent except Calotes minor, in having a dorso-ventrally compressed body. Psammophilus differs from Calotes minor in having small body scales and higher number of around the body scales 80–150 (vs 48–60). Psammophilus are characterized by a medium to large adult body size (SVL mm to mm); body dorso-ventrally compressed; presence of an antehumeral fold; supratympanic spines present, reduced in size; dorsal and lateral scales rows slightly irregular; nuchal and dorsal crest small, reduced; dorsal and lateral scales small, keeled, scale rows directed postero-dorsally. Psammophilus can be distinguished from its sister genus Monilesaurus gen. nov. and Calotes in having a dorso-ventrally compressed body (vs dorso-laterally compressed) and higher number of scales on the mid-body scales (more than 80 vs less than 65) and reduced nuchal crest (vs. well developed); and from Microauris gen. nov. by having a relatively large tympanum (Fig. 9d vs 9b). Scales on head large uniform shield like (vs small, sub-triangular) (Fig. 10c vs 10d). Supratympanic spines are present, in the form of two separated spines vs clusters in Calotes. Psammophilus are sexually dimorphic, adult males are larger than females and have enlarged cheeks. Psammophilus are also sexually dichromatic; during breeding season males acquire bright yellow and orange colors on the dorsum while females remain dull to dark brown with or without orange/ yellow spots (Pal et al. 2018: 437).
Diagnosis and comparison (dorsalis). A medium to large sized Psammophilus characterized by the posterodorsal orientation of lateral scales; antehumeral fold well developed; 94–148 midbody scale rows (vs 115–140 in Boulenger, 1885; 115–150 Smith, 1935); ventral scales 112–152; nuchal crest reduced, composed of 15–18 very small, triangular spines, continuous with almost equal to or even smaller dorsal crest which appears like slightly raised denticulation; dorsal crest absent in females and juveniles; two separated, very small supratympanic spines; dorsal and lateral scales keeled, ventral scales strongly keeled; paired postmentals, first pair separated by 1–2 scales; 24–28 subdigital lamellae under fourth finger, 26–34 subdigital lamellae under fourth toe; 11–13 supralabials and 10–12 infralabials; adult males with uniform greyish brown to black body, dorsum lighter; indistinct lighter blotches on the sides, lip scales lighter grey or off-white; females and juveniles with a pair of dorsolateral stripes from neck to above tail, dorsum and lateral speckled with lighter spots.
Morphologically, P. dorsalis is similar to P. blanfordanus, the only other species known from this group, but can be distinguished by a combination of the following characters: 100–140 midbody scale rows (vs 80–100); three samples collected from eastern India close to the type locality of P. blanfordanus also had lower number 84–94 (80–100 Boulenger 1885 & Smith, 1935). Midbody scales row counts clearly overlap with P. dorsalis. Furthermore, all the meristic characters we checked for few specimens overlap (Appendix 3). There is, therefore a need for more thorough examination of morphological and morphometric characters with a larger sample size to diagnose P. dorsalis from P. blanfordanus.
|Comment||Type species: Agama dorsalis GRAY in GRIFFITH & PIDGEON 1831 is the type species of the genus Psammophilus FITZINGER 1843: 17. Agama dorsalis GRAY is also the type species of the genus Charasia GRAY 1845: 246. Boulenger (1885), considered Oriocalotes and Charasia to be synonyms of Acanthosaura Gray 1831.|
|Etymology||None provided but probably from Latin “Psammo” meaning sand and “Philus” meaning loving.|