Heterochely and laterality in Fredius ibiapaba Santos, Tavares, Silva, Cervini, Pinheiro and Santana, 2020 (Decapoda: Brachyura: Pseudothelphusidae), endemic species from the Ibiapaba plateau, Northeast Brazil

Abstract

ABSTRACT The aim of this study was to investigate whether Fredius ibiapaba presents heterochely and laterality of the larger chela, highlighting its implications for the biology and ecology of the species. We carried out the study with specimens deposited in the carcinological collection of the Laboratório de Crustáceos do Semiárido of the Universidade Regional do Cariri. The results show that adult and juvenile males and females exhibit heterochely, with a more pronounced asymmetry in males. Handedness was exhibited, with a strong righthanded tendency in adult and juvenile males and females. The hypertrophy of one of the chelipeds is especially important for males, as the large chelipeds are used to acquire greater advantages in agonistic encounters, disputes over territory, and feeding, and mainly in the construction of burrows and defence of shelters, increasing reproductive success. The directional energy shift from body growth to cheliped growth, more pronounced in juvenile males, may explain the smaller body size found in males of this species.