Dramatic dietary shift maintains sequestered toxins in chemically defended snakes.

Unlike other snakes, most species of Rhabdophis possess glands in their dorsal skin, sometimes limited to the neck, known as nucho-dorsal and nuchal glands, respectively. Those glands contain powerful cardiotonic steroids known as bufadienolides, which can be deployed as a defense against predators. Bufadienolides otherwise occur only in toads (Bufonidae) and some fireflies (Lampyrinae), which are known or believed to synthesize the toxins. The ancestral diet of Rhabdophis consists of anuran amphibians, and we have shown previously that the bufadienolide toxins of frog-eating species are sequestered from toads consumed as prey. However, one derived clade, the Rhabdophis nuchalis Group, has shifted its primary diet from frogs to earthworms. Here we confirm that the worm-eating snakes possess bufadienolides in their nucho-dorsal glands, although the worms themselves lack such toxins. In addition, we show that the bufadienolides of R. nuchalis Group species are obtained primarily from fireflies. Although few snakes feed on insects, we document through feeding experiments, chemosensory preference tests, and gut contents that lampyrine firefly larvae are regularly consumed by these snakes. Furthermore, members of the R. nuchalis Group contain compounds that resemble the distinctive bufadienolides of fireflies, but not those of toads, in stereochemistry, glycosylation, acetylation, and molecular weight. Thus, the evolutionary shift in primary prey among members of the R. nuchalis Group has been accompanied by a dramatic shift in the source of the species' sequestered defensive toxins.

An authentic record of Eutropis bibronii (Gray, 1838) (Reptilia: Scincidae) from Sri Lanka.

Among the eight species of Eutropis Fitzinger currently known from Sri Lanka, Eutropis bibronii (Gray, 1838) is among the least known. Hence, the occurrence of this species in Sri Lanka has been doubted by some authors since there were no confirmed records from live specimens for the past 70 years. The species has been previously reported mostly from northern regions of Sri Lanka. Here, we report the collection of a live Eutropis bibronii from the Chundikulam National Park in the Northern Province of Sri Lanka confirming its occurrence in the country.

The Re-discovery of live populations of Cnemaspis tropidogaster (Boulenger, 1885) (Sauria, Gekkonidae) from Sri Lanka after 120 years.

Gonatodes kandianus var. tropidogaster was described by Boulenger (1885) with only "Ceylon" (=Sri Lanka) as its locality. This taxon was later assigned to the genus Cnemaspis and then recorded from many different parts of the country. Misleading taxonomic publications and muddled nomenclatural issues has since rendered its taxonomic position unclear. Recent studies have revealed, however, that C. tropidogaster is a species complex, and the species and its types have been redescribed. Unfortunately, no live populations of this species have been recorded until now. Here we report the rediscovery of live populations of this species 120 years after its last collection date records. C. tropidogaster was rediscovered from a low elevation (50-80 m asl.) of the wet zone of Sri Lanka. The rediscovered population was attributed to C. tropidogaster on the basis of a suite of matching morphometric and meristic characters that distinguish C. tropidogaster from other Sri Lankan Cnemaspis.