Species Identification of Shed Snake Skins in Taiwan and Adjacent Islands

Tein-Shun Tsai and Jean-Jay Mao (2017) Shed snake skins have many applications for humans and other animals, and can provide much useful information to a field survey. When properly prepared and identified, a shed snake skin can be used as an important voucher; the morphological descriptions of the shed skins may be critical for taxonomic research, as well as studies of snake ecology and conservation. However, few convenient/ expeditious methods or techniques to identify shed snake skins in specific areas have been developed. In this study, we collected and examined a total of 1,260 shed skin samples - including 322 samples from neonates/ juveniles and 938 from subadults/adults - from 53 snake species in Taiwan and adjacent islands, and developed the first guide to identify them. To the naked eye or from scanned images, the sheds of almost all species could be identified if most of the shed was collected. The key features that aided in identification included the patterns on the sheds and scale morphology. Ontogenetic differences and intraspecific variation in the patterns of sheds were evident in some snake species, and the proportion of young snakes with patterned shed skins was larger than that of adults. The retention of markings on the ventral side of the body (especially the ventral head) during sloughing was much lower than that on the dorsal side. We hope that this pioneering work will not only encourage other researchers to develop similar keys for their country, but also promote local schools, organizations, and citizen scientists to conduct snake inventories.