Comportamento e morfometria do caranguejo Goyazana castelnaui H. Milne-Edwards, 1853, (Brachyura, Trichodactylidae) no Sertão de Pernambuco, Brasil

Abstract

We aimed to investigate the behavioral and morphometric aspects of Goyazana castelnaui H. Milne-Edwards, 1853, proposing to elaborate a behavioral repertoire of the species, describing the activities of the crabs in the natural environment and in the laboratory, as well as characterize the morphometry of juveniles in the first stages of crab using geometric morphometric. The specimens were observed in the Pajeú River, in the Municipality of Floresta, semiarid of pernambuco, from June 2010 to May 2011 and from March 2015 to September 2016. 28 individuals (12♂ and 16♀) were cultured for the behavioral study in Unidade Acadêmica de Serra Talhada, Universisade Federal Rural de Pernambuco, between March 2015 and February 2017. The specimens showed signs of nocturnal habit, cryptic behavior and direct embryonic development. The cheliped were essential for diverse activities such as defense, construction of burrows, mating and feeding. However, in the absence of one or more chelipeds the locomotor pereiopods and maxilliped compensated the absence mainly in the capture of the food. The lost appendages were regenerated in subsequent moult, although adult females showed less potential for regeneration. The pleon was extremely important for the reproductive behavior since in the females they are used as incubation chamber and receptivity sign during court. For males it was used to facilitate and maintain the pleon of the partner opened during copulation. The geometric morphometry of the juveniles presented little variation in the form, in which the dorsal view varied mainly in the posterior and anterolateral regions whereas the dorsal portion presented variations in both the thoracic sternites and the pléon, being not possible the differentiation between males and females.