Molecular phylogenetics and taxonomic reassessment of the widespread agamid lizard Calotes versicolor (Daudin, 1802) (Squamata, Agamidae) across South Asia

The genus Calotes Cuvier, 1817 (Agamidae: Draconinae) is highly diverse, with species occurring in South and Southeast Asia, and Oceania. Most species of the subfamily except C. versicolor have narrow geographic distributions. Calotes versicolor is distributed from western Iran in the west to south China and Indonesia in the east and has been introduced to parts of Africa and North America. The species has had a complicated taxonomic history; multiple species and subspecies related to C. versicolor were described from India and adjoining regions, which were synonymized in subsequent revisions. However, a study of Burmese C. versicolor yielded two new species, C. htunwini and C. irawadi, indicating that C. versicolor is a species complex. Such integrative taxonomic studies have not been carried out in India, the supposed type locality of C. versicolor. Hence, we studied C. versicolor sensu lato from the Indian subcontinent and generated sequences of mitochondrial 16S and COI fragments from tissues sampled from multiple localities in the region, including the type localities of its synonyms. Phylogenetic analyses revealed four well-supported, deeply-divergent lineages, supported by morphological data. These lineages represent (i) C. versicolor sensu stricto, from South India and parts of the east coast, (ii) C. irawadi sensu lato from northeast India and Southeast Asia, (iii) a synonym from the eastern Indo-Gangetic Plains which we resurrect here, and (iv) a subspecies from Pakistan which we elevate to species level. We provide re-descriptions for the resurrected or elevated species, and a diagnostic key to the species of the C. versicolor complex. The study shows that C. versicolor sensu stricto is endemic to parts of southern and eastern India, and not widely distributed, though it may have been introduced to other parts of the world.

Sex-Determination Mechanisms among Populations within Cryptic Species Complex of Calotes (Squamata: Agamidae: Draconinae)

Sex-determination mechanisms and sex chromosomes are known to vary among reptile species and, in a few celebrated examples, within populations of the same species. The oriental garden lizard, Calotes versicolor, is one of the most intriguing species in this regard, exhibiting evidence of multiple sex-determination modes within a single species. One possible explanation for this unusual distribution is that in C. versicolor, different modes of sex determination are confined to a particular population or a species within a cryptic species complex. Here, we report on a population genetic analysis using SNP data from a methylation-sensitive DArT sequencing analysis and mitochondrial DNA data obtained from samples collected from six locations: three from Bangladesh and three from Thailand. Our aim was to determine whether C. versicolor is best described as a single species with multiple lineages or as multiple species, as well as if its sex-determination mechanisms vary within or between species. We present evidence that the latter possibility is the case and that C. versicolor comprises a complex of cryptic species. We also identify sex-linked markers within these species and use them to identify modes of sex determination. Overall, our results suggest that different sex-determination modes have evolved among closely related species and within populations of Agamid lizards.

Environment-Dependent Variation in Gut Microbiota of an Oviparous Lizard (Calotes versicolor)

Vertebrates maintain complex symbiotic relationships with microbiota living within their gastrointestinal tracts which reflects the ecological and evolutionary relationship between hosts and their gut microbiota. However, this understanding is limited in lizards and the spatial heterogeneity and co-occurrence patterns of gut microbiota inside the gastrointestinal tracts of a host and variations of microbial community among samples remain poorly understood. To address this issue and provide a guide for gut microbiota sampling from lizards, we investigated the bacteria in three gut locations of the oriental garden lizard (Calotes versicolor) and the data were analyzed for bacterial composition by 16S ribosomal RNA (16S rRNA) gene amplicon sequencing. We found the relative abundance of the dominant phyla exhibited an increasing trend from the small intestine to the large intestine, and phyla Firmicutes, Bacteroidetes and Proteobacteria were the three primary phyla in the gut microbiota of C. versicolor. There were a higher abundance of genus Bacteroides (Class: Bacteroidia), Coprobacillus and Eubacterium (Class: Erysipelotrichia), Parabacteroides (Family: Porphyromonadaceae) and Ruminococcus (Family: Lachnospiraceae), and Family Odoribacteraceae and Rikenellaceae in the sample from the hindgut. The secondary bile acid biosynthesis, glycosaminoglycan degradation, sphingolipid metabolism and lysosome were significantly higher in the hindgut than that in the small intestine. Taken together our results indicate variations of gut microbiota composition and metabolic pathway in different parts of the oriental garden lizard.

Potential and Challenges on Amphibians and Reptiles Research in West Java

West Java Province has the largest population amongst others in Java, and therefore land conversion rate in the region is increasing. Approximately 40% of forest areas in West Java has been converted between 1990–2015. As a consequence, the number of bi­odiversity in the region is decreasing, including amphibians and rep­tiles. These groups play an important role in the food chain of an ecosystem, and are very sensitive to environmental changes. How­ever, comprehensive research on amphibian and reptile species in West Java is suboptimal. Visual Encounter Survey has performed in seven districts in West Java for one month and has recorded 26 amphibian species and 27 reptile species. These species were in­cluding Javan endemic species (for example: Fejervarya iskandari, Huia masonii, Limnonectes microdiscus, Megophrys montana, and Microhyla achatina), introduced species (Calotes versicolor), and species with a new distribution record (Leptophryne borbonica and Kalophrynus minusculus). In addition, cryptic species (Genus Lep­tophryne and Cyrtodactylus), which are interesting for further stud­ies, were observed. This study has demonstrated that the potential of a comprehensive study of amphibian and reptile species in West Java is great. Apart from this, conserving the biodiversity in the region also challenging due to the high rate in land conversion

Vertebrate prey handling in the Indian Grey Hornbill Ocyceros birostris (Aves: Bucerotiformes: Bucerotidae)

Most hornbills are omnivorous, but there are few specific records of how vertebrate prey are handled by hornbills, particularly in Asia. I describe an observation of a pair of Indian Grey Hornbills Ocyceros birostris handling a large vertebrate prey item (Garden Lizard Calotes versicolor) which included both manipulation (crushing) in the bill and repeated wiping on the branch of a tree, the latter technique undescribed for this or other species of hornbill. Likely reasons for this behaviour are discussed.