Influence of Prey Scent on Chemosensory Behavior of Two Fossorial Earthsnakes: Conopsis biserialis and Conopsis nasus (Serpentes: Colubridae)

Terrestrial, arboreal, and semiaquatic snake species are well known to discriminate among prey types using chemosensation. In contrast, chemosensory capacities of cryptic and fossorial snake species are not well understood. We tested for interspecific differences in the ability of two fossorial earthsnakes, Conopsis biserialis and Conopsis nasus, to detect and discriminate among potential invertebrate and vertebrate prey based on chemical cues alone. Presentation of swabs treated with various prey odor extracts revealed that both snake species were able to detect prey using chemoreception. Chemosensory tongue-flick attack scores and lower latency responses were significantly different for treated swabs when compared to water controls, and interspecific differences were observed. We also found that tongue-flick attack score was higher for invertebrate prey odors than vertebrate prey odors in both earthsnake species. Additionally, differential chemosensory responses to chemicals from different prey types indicated that snakes could discriminate among at least some invertebrate prey types based on chemosensory cues.