Monday, November 21, 2011

[Herpetology • 2005] Calotes desilvai • A new species of agamid lizard from Morningside Forest, Sri Lanka

Fig. 2. Calotes desilvai, paratype female, 75.5 mm SVL,
WHT 5998: dorsolateral view, in life.

The genus Calotes Cuvier has been considered to be represented in Sri Lanka by six species. A seventh species, C. desilvai, evidently restricted to a single site, Morningside Forest (~ 10 km2) on the eastern side of the Sinharaja World Heritage Site, is described. Among the Sri Lankan Calotes, the new species seems most closely related to C. liolepis Boulenger, which is widely distributed in the island’s lowland rain forest and a few isolated moist forests in the dry zone. Calotes desilvai is distinguished from C. liolepis by having the fifth toe 42.6–47.0% of head length in males, 41.9–45.9% in females (vs. 31.0–39.5% and 33.0–40.5% respectively, in C. liolepis); bands on gular area distinct, black (vs. bands on gular area faint, brown); shoulder pit black (vs. shoulder pit cream white to brown); and scales on ventral surface of thigh smooth (vs. scales on the ventral surface of thigh carinate). Males of C. desilvai may also be distinguished from males of C. liolepis by their longer upper arm and femur (49.6–50.0 and 70.3–75.0% of head length, respectively) vs. shorter upper arm and femur (40.3–49.3 and 57.1–69.5%, respectively) and a comparatively short posterior supratympanic spine (1.7–2.7% of head length), longer in C. liolepis (3.1–12.9%).

KEYWORDS. – Agamidae, Calotes, new species, distribution, Sri Lanka

Fig. 6. Map of Sri Lanka illustrating the distribution of Calotes liolepis (solid circles) and Calote desilvai (solid square), based on material examined in this study

Etymology. – The species epithet is an eponym Latinized in the genitive singular, honouring Anslem de Silva, founder of the Amphibia and Reptile Research Organisation (ARROS) and patron of herpetology in Sri Lanka for more than the past three decades.

Distribution. – Calotes desilvai is known only from the type locality, Morningside Forest Reserve (1,080 m alt.) and adjacent forest, over a range of ~10 km2 at the eastern border of Sinharaja World Heritage Site (Fig. 3).

Natural history notes. – We observed egg-bearing females at the type locality in February, 2004. Female paratype WHT 5998, 75.5 mm SVL, had two creamy-white eggs measuring 16.2×8.9 mm and 16.5×8.5 mm. This lizard was observed only on tree trunks 2–5 m above ground between 9 and 15 h. It is restricted to areas of dense, undisturbed forest, being absent from secondary forest and scrub habitats.

Calotes desilvai is sympatric in its type locality with the agamids Otocryptis wiegmanni Wagler, 1830, Cerataphora erdleni and Cerataphora karu Pethiyagoda & Manamendra-Arachchi, 1998, all of which are endemic to Sri Lanka. We recorded Calotes desilvai only from undisturbed, closed-canopy forest at Morningside. Calotes liolepis however, inhabits all forest types, including home gardens and rubber plantations; we even observed this species on shade trees in tea plantations.

The conservation status of Calotes desilvai is discussed in a separate paper (Bahir & Surasingha, 2005: this volume).

Mohomed M. Bahir & Kalana P. Maduwage. 2005. Calotes desilvai, a new species of agamid lizard from Morningside Forest, Sri Lanka. Raffles Bulletin of Zoology Suppl. 12: 381–392.