(SQUAMATA: SCINCIDAE: LANKASCINCUS)

Lankascincus greeri, a new species of litter skink, is described from Sri Lanka. The new species, which is widely distributed throughout the rainforests of the south-western lowlands, is distinguished from all other members of this genus by the presence of paired frontoparietals; possessing 2 secondary temporals in contact with each other; and by having 42-45 paravertebrals, 18-21 subdigital lamellae on fourth digit of pes and a maximum SVL of 58.5 mm. A paratype of Sphenomorphus dorsicatenatus is rediscovered (the type series having long been considered lost) and assigned to Lankascincus. Key words: Reptilia, Sphenomorphus, endemism, Ceylon, Lygosominae Doi: 10.4038/cjsbs.v36i2.482 Cey. J. Sci. (Bio. Sci.) 36 (2): 80-87, 2007


INTRODUCTION
In a review of the Sri Lankan members of the lygosomine skinks previously assigned to Sphenomorphus Fitzinger, 1843, Greer (1991) made available the new genus Lankascincus, in which he included three previously described species (L.deignani, L. fallax, L. taprobanensis) while adding three new ones (L.deraniyagalae, L. gansi and L. taylori).Two further species, L. munindradasai and L. sripadensis, were added to Lankascincus recently by Wickramasinghe et al. (2007), from the highlands of Sri Lanka.The genus Lankascincus is presently considered endemic to Sri Lanka.
A national survey of lizards in Sri Lanka was conducted by the Wildlife Heritage Trust between 1998 and 2005.This survey while serving to delineate the ranges of known species and assess their conservation status also led to the discovery of new taxa.Here, using a morphological approach, we describe a new species of Lankascincus that was discovered in the course of this survey, in the island's lowland rainforests.The review of historical material associated with this study also led to the rediscovery of a paratype of Sphenomorphus dorsicatenatus Deraniyagala, 1953, in the National Museum of Sri Lanka, which was found to be a valid and extant species of Lankascincus.

MATERIALS AND METHODS
Methods for meristic data follow Andreone and Greer (2002); measurements were made using an Olympus SZ40 dissecting microscope.Head length (measured from snout tip to posterior margin of ear opening), eye diameter (greatest diameter of eye), and external ear opening (greatest length of ear opening), were measured to the nearest 0.1 mm using KWB dial Vernier callipers.The following measurements were taken to the nearest 0.5 mm using a steel ruler: snout-vent length (SVL, from tip of snout to anterior margin of vent); tail length (from anterior margin of vent to tip of unregenerated tail); trunk length (from axilla to groin); forelimb length (from forelimb insertion to tip of fourth finger, excluding claw); hind-limb length (from hind-limb insertion to tip of fourth toe, excluding claw).
A Canon IXUS 50 digital camera was used for colour photography.Descriptions of colour in preservative are based on freshly-preserved examples.
Comparisons were made with preserved material in the collection of Natural History Museum, London, England (BMNH); National Museum of Sri Lanka, Colombo, Sri Lanka (NMSL); and Wildlife Heritage Trust of Sri Lanka (WHT).Additional sources of information include Deraniyagala (1931, 1953), Taylor (1950), and Greer (1991)._________________________________ *Corresponding author's email: rohanp@slt.lkAltitudes are given in metres above mean sea level; geographic co-ordinates were taken using topographic maps (1 inch: 1 mile, Survey Department, Colombo) and in some instances, with a Magellan 12-channel GPS (geodetic datum WGS-84: World Geodetic System, 1984).Specimens collected in the course of this study are deposited in NMSL and WHT.
Comparative material examined in this study is listed in the Appendix.
Mental and postmentals wider than long, in contact with first infralabial only; infralabials 5; pairs of enlarged chin shields 3, the first in contact with each other, the second and third separated by a single row of scales (the third also separated from infralabials by a single scale row).

Colouration
In life (Plate 1), ground colour yellowish brown; head with a series of pale spots dorsally; prominent white spots laterally on neck; a distinct white blotch present beneath eye; tail reddish, with blackish, interrupted longitudinal lines at base.In preservative, dorsally light brown, becoming progressively paler on sides and venter.Interrupted dark longitudinal lines present on dorsum, prominent on base of tail; similar lines well-defined on hind-limbs.Supralabials and infralabials with black spots.

Etymology
The species is named for Allen E. Greer of the Australian Museum, Sydney, in recognition of his many contributions to the taxonomy of Scincidae.The name is Latinized as a noun in the genitive singular case.

Distribution and natural history
Lankascincus greeri is widely distributed among the forested areas of south-western Sri Lanka, including the Sinharaja World Heritage Site, Kanneliya Forest Reserve, Kombala-Kottawa Forest Reserve and Beraliya Forest Reserve (Fig. 2).It is restricted to lower elevations (< ~ 500 m).
Individuals of L. greeri were observed in leaf litter and under large stones.It is a relatively rare species, hitherto known from only the five specimens of the type series, which comprise four males and a juvenile (sex not determined).Lankascincus greeri occurs in sympatry with two congeners (L.fallax and L. gansi), and the skinks Eutropis carinata lankae and E. macularius macularius.
Although Greer (1991) and Austin et al. (2004) considered Sphenomorphus dorsicatenatus Deraniyagala, 1953 (type locality Angamana, near Nivitigala) to be a species incertae sedis, they tentatively assigned it to Lankascincus.The types of this species have long been considered lost (Greer, 1991).In the course of this study, one of the paratypes was discovered during a search of materials in the collection of the NMSL.Sphenomorphus dorsicatenatus is distinguished from L. greeri by having the secondary temporals separated by the upper primary temporal (vs secondary temporals in contact) and possessing only a single (vs 2) post-supralabials.We consider it to be a valid species, widely distributed in the lowland rainforests of Sri Lanka (e.g., Sinharaja, Kottawa, Kanneliya and Beraliya).A related but distinct and as yet undescribed species occurs in the environs of Kandy, a description of which, together with an analysis of the interrelationships of Lankascincus, is presently in preparation (work in progress).
The only other lygosomine species incertae sedis from Sri Lanka is Lygosoma megalops Annandale, 1906, the types of which are evidently lost (Deraniyagala, 1953;Greer, 1991).The original description, however, is sufficiently detailed for this species to be distinguished from the new species described herein.Lankascincus greeri differs from 'Lygosoma' megalops by having the parietals posteriorly in contact with each other, 7 supralabials, and 10 or 11 supraciliaries (vs parietals clearly separated by interparietal, 6 supralabials, and 7 or 8 supraciliaries in 'Lygosoma' megalops).Deraniyagala (1931Deraniyagala ( , 1953) ) recorded Lygosoma dussumieri Duméril & Bibron, 1839 (type locality 'Malabar', i.e., the south-western littoral of India, now in Kerala State), from Peradeniya, near Kandy, in central Sri Lanka.While the lack of surviving voucher material precludes verification of this record, Deraniyagala's description allows separation of that taxon from the new species herein described by the number of mid-body scale rows: Lankascincus greeri has 26-28, whereas the Sri Lankan 'Lygosoma' dussumieri was noted by Deraniyagala (1931) to have 38-40.
While L. greeri occurs in anthropogenic habitats, it appears to depend on a high degree of shade and leaf litter and is uncommon or altogether absent in highly disturbed habitats (unlike, e.g., the almost synanthropic L. fallax).The reduction and elimination of leaf litter and forest undergrowth that inevitably accompanies deforestation (Andreone and Greer, 2004) could, therefore, impact on this species.Widespread burning continues to devastate significant extents of secondary forest in Sri Lanka each year (Batuwita and Bahir, 2005), posing further threats to ground-dwelling species.