Gonads of males and females of the mangrove tree crab Aratus pisonii (Grapsidae: Brachyura: Decapoda): A histological and histochemical view

Abstract

This study describes the microscopic anatomy of the male and female gonads and the spermatogenesis and oogenesis of the mangrove tree crab Aratus pisonii. Males and females were captured in a mangrove marsh in Guaratiba (23°04′S, 44°10′W), Rio de Janeiro State, Brazil. The testes are composed of spermatogonia I (7.82±0.84μm), spermatogonia II (6.12±0.72μm), spermatocytes I (5.62±0.71μm), spermatocytes II (5.00±0.42μm), spermatids (4.01±0.33μm), and spermatozoa (2.58±0.18μm). The spermatozoids are sent to the vas deferens, which is divided into three regions: anterior vas deferens, middle vas deferens and posterior vas deferens. There are no indications of development as the production of male gametes was continuous throughout the study period. In the females, there are four ovary development stages: previtellogenesis, early-stage vitellogenesis, mature vitellogenesis, and postspawning. Five types of cells were found in the gonads: oogonia (5.23±1.31μm), oocytes in early development (19.84±5.16μm), previtellogenic oocytes (49.49±6.87μm), vitellogenic oocytes (87.51±10.23μm), and mature oocytes (174.78±29.46μm). The findings of this study indicate that A. pisonii females lay eggs on multiple occasions throughout the study period. © 2011 The Authors. Acta Zoologica © 2011 The Royal Swedish Academy of Sciences.