Dorsal Snake Scale Microdermatoglyphics: Ecological Indicator or Taxonomic Tool?

The dorsal scale microdermatoglyphic patterns of 40 species of snakes were analyzed to determine whether any correlation exists between the habitat preferences of the species and their microdermatoglyphic patterns. Ten species were selected from each of four major habitats; desert sand dwelling, burrowing, aquatic, and arboreal. The scales were analyzed for amount of variation within each species group, and for the number of patterns seen in more than one group. No single pattern was found to predominate in any of the habitats, and each group exhibited a wide diversity of patterns. The same or very similar patterns were often found in snakes of different habitat preferences. Indications are that microdermatoglyphic patterns reflect phylogenetic relationship rather than ecological or habitat factors. The great radiation of squamate rep- tiles during the Cenozoic Era has re- sulted in a diversity of snake species characterized by relatively little mor- phological variation. This poses a par- ticular problem for herpetologists deal- ing with the approximately 400 genera and 2350 species of the suborder Ser- pentes. The paucity of major morphological variation in the Serpentes in general and the poor fossil record of the group have led to a proliferation of widely differing schemes of classification based on often subjectively weighted phylo- genetic characters inherent in minor body structures. (Some of these charac- ters may, in fact, be correlated with the ecology, locomotion, or food habits of the animals, and hence of questionable value.) Traditional taxonomists have used many of the same features of scale placement, tooth structure, and general