Oplurus

Abstract: The structure and topography of cutaneous receptors of 21 species of iguanian lizards were studied using histology and scanning electron microscopy. Sense organs with "hairs" are found in the integument of Ceratophora, Draco, Phrynocephalus, Stellio, and Trapelus (agamids), and in Anolis, Chal- arodon and Oplurus (iguanids). Sense organs without "hairs" are found in the integument of Physignathus (agamid) and Sceloporus (iguanid). The chameleons have generalized epidermal receptors with simplified structure. Familial differences were observed in the numbers of receptors on the scales of the head and the tail: iguanids have 5-7 times more receptors than agamids. Physignathus differs from other agamids in the morphology, size, and number of receptors. These receptors are hypothesized to serve several functions (as mechano- and thermoreceptors, and possibly sensitivity to humidity). Integumental sense organs were first de- scribed for reptiles in 1868 by Leydig in the lizard genera Lacerta and Anguis, and in the snake genus Coronella. The small depressions he found in the surface of their scales were considered "organs of the sixth sense"; Leydig compared them with the taste buds of fishes

Abstract: We report the development of 18, single-copy, anonymous nuclear loci from the Malagasy plated lizard Zonosaurus madagascariensis. More than 140 clones from a genomic library were examined and 38 potential loci tested across both closely and distantly related lizards. Of the 18 loci reported here, more than half (10) work in closely related zonosaurines although only one successfully amplified a homologous fragment in the distantly related iguanid (Oplurus). Sequences of these loci revealed a high frequency of single nucleotide polymorphisms, supporting previous reports of high levels of intraspecific variation in lizards.

Abstract: The topography and numerical distribution of the skin receptors in 29 lizard species including 18 agamids, eight iguanids and three gekkonids, are compared and contrasted. There are no marked differences in the number of receptors in the dorsal and ventral surfaces of the body in the different groups. The maximal density of the receptors occurs on the head and decreases in the caudal direction. Iguanids and gekkonids have 5–6 times more receptors than agamids. Agamids Gonocephalus grandis from S.E. Asia, Pogona barbata, Diporiphora bilineata from Australia and Ceratophora tennentii from Sri-Lanka, however, are distinguished by their high density of receptors, especially on the head. Species of Physignathus are similar to iguanids in this way. The agamid Phrynocephalus mystaceus shows considerable differences, in receptor number, from other species of this genus. There is a high density of receptors on the caudal scales of the Madagascan iguanid Oplurus, and a similar high density of receptors on the ventral surface of the gecko Teratoscincus scincus.

Abstract: The iguanid subfamily Oplurinae consists of seven species of small to medium-sized, arboreal, sand-dwelling or rock-dwelling lizards endemic to Madagascar and the Comoros, belonging to the genera Oplurus and Chalarodon. We here present the first complete molecular species-level phylogeny for Oplurinae based on DNA sequences (865 bp) of the mitochondrial 16S rRNA gene and the nuclear c-mos gene. Our study is based on 52 specimens sampled from different populations in Madagascar and includes the geographically isolated population from Grande Comore, hitherto considered as subspecies Oplurus cuvieri comorensis or even as a separate species O. comorensis. Our results confirm that, within the genus Oplurus, the largely arboreal O. cuvieri and O. cyclurus form the sister clade to the remaining, more rock-dwelling species. Within the latter lineage, Oplurus quadrimaculatus is placed most basal, O. fierinensis and O. grandidieri are closely related sister species with high support, and O. saxicola is sister to the fierinensis/grandidieri lineage. Within the arboreal Oplurus, the Comoran sample shows no genetic differentiation relative to O. cuvieri populations from the North West and Sambirano regions of Madagascar, indicating that this population should not be considered as a separate species. In the monotypic genus Chalarodon, we discovered deep genetic divergences among populations of C. madagascariensis indicating the presence of a previously unrecognized cryptic species and the need for taxonomic revision.