Bronchocela rubrigularis Hallermann, 2009

Chandramouli, S. R., Adhikari, Omkar D., Amarasinghe, A. A. Thasun & Abinawanto, A., 2023, A review of the genus Bronchocela Kaup, 1827 (Reptilia: Agamidae) in the Nicobar Archipelago with the description of two new species, Zootaxa 5254 (4), pp. 493-516 : 499-502

Bronchocela rubrigularis Hallermann, 2009

( Fig. 3 )

Bronchocela jubata (non Duméril & Bibron, 1837)— Stoliczka (1870); Theobald (1876) part

Calotes jubatus (non Duméril & Bibron, 1837)— Boulenger (1885; 1890); Annandale (1905); Smith (1935) part

Material studied: DOSMB 05086, an adult male and DOSMB 05087, an adult female, from near the APWD guest house, Camorta (8.03792ºN, 93.54263ºE, 28 m asl.), BNHS 1609, an adult female from Nancowry.

Holotype: ZMH R09271, an adult male collected from Triket Island , Central Nicobar Islands ( Fig. 4 ).

Differential diagnosis and comparisons: A species of Bronchocela endemic to the Central group of Nicobar Islands characterized by: large body size (82.3–106.4 mm SVL); relative tail length (338 % SVL); 50–58 scale rows around mid-body, of which, the first two to three rows on the dorsum oriented posterodorsally, the next 4–5 rows oriented posteriorly, followed by 10–11 rows oriented posteroventrally; 10–11 enlarged, elongated and backwardly curved scales forming the nuchal crest; dorsal crest relatively well developed, composed of enlarged scales in the form of a well-defined serrated ridge; three postmentals; 7–10 supralabials; 7–10 infralabials; six canthals; 6–7 supraciliaries; 27–32 subdigital lamellae under toe IV; 68–77 ventrals; bright grass green dorsal colouration with a bright yellow and black coloured ring around the eyes in both sexes and a red, triangular gular patch in males ( Table 2 ).

Description and variation: A large bodied species of Bronchocela (mean SVL 86.95 mm; n=10), with a long, tapering tail (TaL:SVL 3.37, n=7). Body relatively short and robust (AG:SVL 0.44, n=3). Head large (HL:SVL 0.27); longer than broad (HL:HW 1.83) and about as broad as deep (HW:HD 0.99, n=3). Snout less than half as long as the head (ES:HL 0.44) with a blunt, broadened and rounded tip. Canthus rostralis sharply defined, with six canthal scales. Orbit relatively large, a little less than 1/4 th the length of the head (ED:HL 0.20); tympanum circular, relatively slightly large, a little larger than half the orbit diameter (TYH:ED 0.72) and black in colour. Scales between the eye and tympanum fairly enlarged. Nasal relatively large and ovoid in shape. Scales on the check below the tympanum slightly enlarged; the first two rows smooth and those below keeled. Mental semicircular, bounded by three small postmentals and nine infralabials on either sides. Rostral relatively small, bounded by seven to ten supralabials on each side. Nostrils separated from each other by seven small internasals. Nuchal crest composed of seven to eight elongated, backwardly curved scales projecting posterodorsally. Dorsal body scales fairly enlarged, feebly keeled and homogeneous, in 50-58 (n=11) rows around the mid-body. Of the dorsal scales, the first row on the dorsum on either sides oriented posteriorly; the next two to three rows of scales oriented posterodorsally, with the rest of the scales on the lateral body oriented posteroventrally. Ventrals 60-68 in a longitudinal series; much larger (about twice) than the dorsal scales, bearing a strong median keel, projecting posteriorly towards the lower vertex. Limbs relatively robust and elongate; upper arm short and slender (UAL:SVL 0.18, n=3); lower arm nearly as long as the upper arm (UAL:LAL 1.06, n=3); palm about as long as the lower arm (LAL:PAL 1.03, n=3). Fingers long and slender, relative length of fingers IV>III>V≥II>I. Thigh long and robust (FEL:SVL 0.24, n=3); tibia slightly shorter than thighs (FEL:TBL 0.93, n=3); foot elongated, slightly longer than thigh (FEL:FOL 0.84, n=3). Hindlimbs longer than half the body length (HLL:SVL 0.98, n=10). Relative lengths of toes IV>III>V>II>I; 24-27 subdigital lamellae under toe IV.

Dorsal and ventral coloration verdant green throughout the body; tip of the tail reddish. Head yellowish green both dorsally and ventrally. Sides of the lips, cheeks yellow and eyelids with a black ring around. Tympanum black and the throat with a bright red triangular patch in males. In preservation, dorsal green colouration present in the recently collected samples while the old ones uniform dark throughout. Trunk and belly dark grey. The red throatpatch grey in preservation.

Distribution and Natural history: Endemic to islands of the central group of Nicobars and recorded during the present study from Camorta, Katchall, Teressa and Nancowry Islands. Has been reported from Trinkat, Bompoka, Chowra and Tillanchong Islands ( Hallermann 2009). Arboreal and diurnal in habit. A fairly common species found in a variety of habitats ranging from evergreen forests, secondary forests and plantations to home gardens ( Fig. 8 ).

Figures

FIGURE 3. Bronchocela rubrigularis (top: DOSMB 05086, middle: live male, below: live female).

FIGURE 4. Head of the holotype of Bronchocela rubrigularis (ZMH R09271) (Photo: J. Hallermann).

FIGURE 8. Map, showing the distribution of the four Bronchocela species in the Nicobar Archipelago (red triangles indicate type localities).