41 research outputs found
Illegal Philatelic Issues in the Name of the Republic of Rwanda, Depicting Sri Lankan Snake Images
Seasonal Fluctuation and Population Distribution of Otocryptis wiegmanni, Wagler, 1830 (Reptilia: Agamidae) Inhabiting a Tropical Lowland Rain Forest of Sri Lanka
The seasonal fluctuations of population density and distribution of Otocryptis wiegmanni inhabiting indifferent habitats of the Yagirala forest reserve of Sri Lanka was investigated during the north-east, first inter-monsoon, south-west and second inter-monsoon seasons of the year 2014. Three linear transacts, each measuring 200 m in length were marked along the natural forest, degraded forest and riverine forest habitats. All transects were surveyed by visual encounter survey (VES) method. Ambient temperature, relative humidity, canopy cover and leaf litter moisture content were measured in three points of each transect (50, 100 and 150 m) and the monthly total rainfall data was obtained from Meteorological Department. The highest mean adult population density and the highest number of juveniles were recorded during the relatively dry north-east monsoon season. O. wiegmanni preferred the degraded forest habitat (0.027±0.020 lizards/m2) compared to the natural (0.007 ± 0.006 lizards/m2) and riverine forest habitats during all four climate seasons. Fluctuations in the population density varied according to season and habitat conditions. This species fed mostly on insects of the Orders Orthoptera, Coleoptera and Hymenoptera, and the common breeding season was during the north-east monsoon (NEM) in January-February period. Key words: Yagirala forest reserve, agamid, kangaroo lizard, habitat preferenc
Higher-level molecular phylogenetic relationships of the endemic genus Lankascincus from Sri Lanka based on nuclear DNA sequences
The island of Sri Lanka, located off the tip of the Indian peninsula, has an amazingly diverse and highly endemic herpetofaunal assemblage despite its close proximity to the mainland. Lankascincus, a scincid genus endemic to the island of Sri Lanka, is one of the most common skinks found on the island
Molecular evidence for the taxonomic status of Hemidactylus brookii group taxa (Squamata: Gekkonidae)
Hemidactylus brookii
has one of the widest distributions and, arguably, one of the most confused taxonomic histories of any
gekkonid lizard. Nuclear (RAG1 and PDC) and mitochondrial (ND2, cyt
b
) DNA sequence data were employed to examine
relationships among a sample of putative
H. brookii
, including a topotypical specimen from Borneo. Two clades were recovered,
one consisting of specimens from Borneo (Sarawak), Myanmar, Peninsular Malaysia and Karnataka, southwestern India, and
another of specimens from Sri Lanka, Mauritius and Kerala, southwestern India. Both clades are well supported and deeply
divergent from one another, whereas genetic variation within each clade is limited. None of the analytical approaches used
recovered a well-supported monophyletic
H. brookii sensu lato
. Near uniformity of
H. brookii
sensu stricto
in East Asia suggests
that this species has spread to this region relatively recently. The name
H. parvimaculatus
Deraniyagala 1953 is available for
the Sri Lankan clade and this form should be treated as a valid species. Existing data cannot be used to distinguish whether
this species has colonized Sri Lanka from South India or vice versa. The Palghat Gap provides a candidate barrier to gene
flow between
H. brookii
and
H. parvimaculatus
. Although the identity of
H. brookii
complex geckos in East Asia and Sri
Lanka appears resolved, the situation in India and Pakistan remains complex and thorough revisionary work, coupled with
phylogenetic studies, is needed to determine species boundaries in this regio
Evolution of nuchal glands, unusual defensive organs of Asian natricine snakes (Serpentes: Colubridae), inferred from a molecular phylogeny
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
Were human babies used as bait in crocodile hunts in colonial Sri Lanka?
Use of live animals as bait is not an uncommon practice in hunting worldwide. However, some curious accounts of the use of human babies as bait to lure crocodiles in sport hunting exist on the island of Sri Lanka, where sport hunting was common during the British colonial period. Herein we compile the available records, review other records of the practice, and discuss the likelihood of the exercise actually having taken place. </div
Were human babies used as bait in crocodile hunts in colonial Sri Lanka?
Use of live animals as bait is not an uncommon practice in hunting worldwide. However, some curious accounts of the use of human babies as bait to lure crocodiles in sport hunting exist on the island of Sri Lanka, where sport hunting was common during the British colonial period. Herein we compile the available records, review other records of the practice, and discuss the likelihood of the exercise actually having taken place. </div