Lip-curling in redbelly snakes (Storeria occipitomaculata): functional morphology and ecological significance

Redbelly snakes Storeria occipitomaculata have a characteristic agonistic d isplay involving conspicuous lip-curling and head distortion. The lip-curli ng and head distortion display is similar to head shape-changes during feed ing. Storeria occipitomaculata produced mouth secretions while displaying. Micrographs of maxillae and observation of changes in head configuration sh owed that the lip-curling behaviour of S. occipitomaculata is related to th e presence of carina-bearing maxillary teeth, which are protruded from the mouth during the display. I compared the behaviour and morphology of this s pecies to other gastropod-eating snakes and suggest that these behavioural and morphological characteristics have a two-fold role: in prey capture the y aid the capture, the handling, and perhaps the digestion of prey; in pred ator deterrence they may act as delivery agents for mouth secretions.