Document Type : Original Article
Generalitat de Catalunya, Catalonia, Spain
CRARC, Catalonia Reptiles and Amphibians Rescue Center, Masquefa, Catalonia, Spain
Geometric techniques allow to be applied easily to many zoological problems. Pseudemys concinna is a large terrapine species known as the Eastern River Cooter, native to North America, with a yellow plastron is yellow. The plastral pattern tends to fade with age. In this study, we applied geometric techniques to assess size in a sample of 20 fresh corpses of P. concinna (18 females and 2 males), from which we also obtained colour (red, blue, and green channels) on plastron -lower shell-, to objectivize this fading pattern. A negative regression between size and colour was registered, so colour plastral intensity of Pseudemys concinna LeConte 1830 tends, effectively, to fade with age. Elucidating the cellular and chemical mediators, and mechanisms, of these slow colour changes will likely require laboratory study. Our observation also opens the door to study if animals in natural habitat present similar plastron pigment production. Elucidating the cellular and chemical mediators, and mechanisms, of these slow colour changes will likely require laboratory study.