Eutropis multifasciata (Kuhl, 1820)

Eutropis multifasciata View in CoL .

– Eutropis multifasciata is a common, diurnal, forest-floor skink that spends much of its time basking and foraging in relatively open areas with direct sunlight. In the Seribuat Archipelago, many populations manifest significant departures from this behavior and/or morphology. On P. Cebeh and P. Sepoi, this species occurs in high densities and is active at night. Specimens on both islands were observed crawling and running through the leaf litter during the evening hours. It was originally believed these lizards were frightened out of hiding by our lights. But with lights off, lizards could be heard moving through the leaf litter. The skinks from P. Cebeh are inordinately thick and robust and from a distance, do not even appear to be E. multifasciata . On P. Sepoi and the Tokong Burung group, E. multifasciata occur in the intertidal, living and foraging in and among the rocks and crevices. At first glance we mistook these skinks for Emoia atrocostata . Eutropis multifasciata has a relatively modest degree of colour pattern variation in its continental forms (see Chan-Ard et al., 1999). On small islands in the Seribuat Archipelago, this variablilty is often fixed and taken to extremes. On the large islands of Tioman, Aur, Tinggi, Sibu, and Babi Besar, E. multifasciata has the typical pattern of a bronze-coloured dorsum, dark flanks with black-edged white spots, and a cream-coloured venter. On P. Sepoi, adult males are uniformly grey in colour whereas females and juveniles are greyish with light green flanks bearing yellow spots. On P. Seribuat and P. Sembilang all skinks have a grey dorsum and bright orange flanks. On the Tokong Burung group, males and females are a uniform greenish gold. The juveniles, however, have metallic green flanks. Skinks from P. Tokong Bahara are the most distinctive of all. The head, forepart of the body, and forelimbs are coppery orange; the posterior of the body, hind limbs, and legs are olive green. The posterior of the jaws are bright orange, and the chin and throat are yellow. The body is relatively narrow (especially when compared to those of P. Cebeh) and original tails are nearly twice the length of the body. Morphological investigations indicate that each one of these populations differ significantly from one another and from mainland populations (A. Ponce, unpublished). Molecular analyses are currently underway to determine their species status and relationships.

All the skinks living on the three islands of the Tokong Burung group and P. Tokong Bahara reside within the tern rookeries, taking refuge in the rocks, cracks, and grass hummocks. Other insular lizard populations living within seabird rookeries derive a significant portion of their resources from the birds in the form of regurgitated food and the arthropods attracted to the nests (e.g., Barrett et al., 2005; L. Grismer, 2002; Hews, 1990; Rounsevell et al., 1985). We suspect the same is happening with Seribuat Archipelago populations. One of us (LLG) observed a skink eating a portion of regurgitated fish from a nest on Tokong Burung Condong.