CONSERVATION GENETICS OF THE COMMON SNAPPING TURTLE (CHELYDRA-SERPENTINA)

Previous studies of relationships among the subspecies of snapping tur tles (Chclydra serpentina) based on morphological and osteological cha racters have been inconclusive. We investigated relationships among th e four currently recognized subspecies using restriction endonucleases yielded 90 variable fragments that define 11 different haplotypes. In dividuals of the two North American subspecies, C.s. osceola and C.s. serpentina, are closely related, differing by a maximum of 0.5% sequen ce divergence. The Central American subspecies, C.s. rossignonii and C .s. acutirostris, are more distinct, both from each other (a minimum o f 1.7% sequence divergence) and from the North American samples (an av erage of 4.45% sequence divergence). The degree of allozymic variation among the four subspecies was found to be limited and could not be us ed to diagnose the four recognized subspecies. The mtDNA data presente d here support the species-level distinctness of C.s. rossignonii and C.s. acutirostris from each other and from a C.s. serpentina-C.s. osce ola complex. The recognition of three distinctive groups of Chelydra r ather than one widespread polytypic species has important conservation implications because it focuses attention on the poorly known middle and South American species.