Records of Body Bending Behavior (‘Liana Crypsis’) in Five Snake Species in Thailand and One in Spain

Hitherto, body bending behavior (BBB) has been reported for less than a dozen of different snake species from tropical and subtropical America. Most authors assume that this rarely documented behavior is cryptic and antipredator, e.g., by taking the form of a liana the snake may avoid being attacked by a potential predator. We herein report the first records of this behavior in snakes in Asia and Europe. A dozen cases of body bending are documented for the colubrids Coelognathus radiatus (Boie, 1827), Ptyas carinata (Günther, 1858) and Oligodon joynsoni (Smith, 1917), and Malpolon monspessulanus (Hermann, 1804), and the natricids Fowlea piscator (Schneider, 1799) and Rhabdophis siamensis (Mell, 1931). In addition to the earlier reports from the New World, we suggest that BBB is widespread in snakes throughout the tropical and subtropical world. For a number of species that display it relatively frequently, such as C. radiatus in Thailand, BBB may have a significant adaptive value. We propose that this behavior is basically a kind of defensive immobility response that may develop swiftly or rather slowly and which is most often associated with diurnal activity, open spaces and an inclination to aggressive defenses. Our data suggest that its function is more often aposematic than cryptic.