Search

Abstract: The aim of this study was to characterize the morphology and function of each section of the reproductive system of male Callinectes danae, as well as the stages of reproductive development and their relation to secondary sexual characteristics. Development of their reproductive system begins after completion of the pubertal moult. The growth of the gonopodium showed negative allometry for both juveniles and adults. The reproductive system is divided into portions with different functions. There is a germinal zone in the testes containing spermatogonia, a zone of maturation containing spermatocytes, spermatids or spermatozoa, as well as a collecting duct, which carries spermatozoa to the vas deferens. There are two matrices in the anterior vas deferens that initiate the separation of spermatozoa groups, one composed of polysaccharide acids (matrix I) and another consisting of neutral polysaccharides (matrix II). In the median vas deferens, the matrix II forms an acellular capsule, which forms the spermatophores. In the posterior vas deferens, the matrices are accumulated, initially with a granular texture and are homogenous for the final portion. The ejaculatory duct and penis have muscle lining to expel the spermatophores at copulation. Even after copulation, males retain a stock of spermatophores, allowing copulation with other females. [ABSTRACT FROM AUTHOR]

Shinozaki-Mendes, R.A., Silva, J.R.F. and Hazin, F.H.V. 2011. Development of male reproductive system of the blue land crab Cardisoma guanhumi Latreille, 1828 (Decapoda: Gecarcinidae). - Acta Zoologica (Stockholm) 93: 390-399. In this study, the reproductive tract of the Cardisoma guanhumi was described both macroscopically and microscopically. The maturation stages of the reproductive system were defined, and the development of germ cells was described. The reproductive tract is made up of a pair of testis, a pair of vas deferentia, and a pair of ejaculatory ducts. The germ cells were classified in the order of development as spermatogonia (diameter: 10.5 ± 0.11 μm), spermatocytes (9.7 ± 0.07 μm), spermatids (initial phase: 5.5 ± 0.06 μm; final phase: 4.3 ± 0.05), and spermatozoa (SPZ) (4.0 ± 0.03 μm). The testis is made up of a germ zone, a maturation zone and collector ducts, which lead to the anterior vas deferens (AVD), containing solely SPZ. The spermatophores (SPH) start to be formed in the AVD, through the secretion of spermatophoric and protein matrices. In the median vas deferens, the SPH, already fully formed, are stored, while in the posterior vas deferens, a large production of a glycoprotein matrix is observed. Based on macroscopic and microscopic description of the male reproductive tract, three maturation stages are proposed: immature, maturing, and mature. [ABSTRACT FROM AUTHOR]