MALE REPRODUCTIVE SYSTEM OF THE RED CHERRY SHRIMP NEOCARIDINA DAVIDI (CARIDEA)

FERNANDO ZARA; MARIA ALICE GARCIA BENTO; ANA LAURA TOMAS; LAURA S. LÓPEZ GRECO

Buenos Aires, CABA

Jornada; Reunión conjunta de sociedades de biociencias; 2017

MALE REPRODUCTIVE SYSTEM OF THE ?RED CHERRY SHRIMP? NEOCARIDINA DAVIDI (CARIDEA)Caridea is a diverse taxon of marine, freshwater and brackish shrimps poorly studied as far as their reproductive anatomy. This study aimed to describe for the first time the functional anatomy of the male reproductive system in an Atyidae, Neocaridina davidi, a very popular ornamental species. For this purpose mature males were cold-anaesthetized and their reproductive systems were dissected for routine histological and histochemical tests. Male reproductive system consists of two coiled testes continuous to the vasa deferentia opening in the gonopores located in the coxae of the fifth pair of pereiopods. Testes are positioned on the dorsal side of the cephalothorax, above the hepatopancreas and below the heart. Testes comprise seminiferous tubules where spermatogenesis occurs. Each vas deferens (VD) is a long tube dorsolaterally positioned with respect to the hepatopancreas, and divided in proximal, middle and distal zones. The proximal part has a cylindrical epithelium with secretory cells while in the proximal to medial zone the vas deferens has a dorsal fold with high columnar epithelium with secretory activity, the typhlosole. This typhlosole is similar to that observed in Macrobrachium rosembergii, yet different from those in penaeid shrimps. The VD increases in diameter distally and the spermatophore (SPF) formation begins at the proximal part of VD. The SPF is a continuous cord with two acellular layers: the inner is thicker with high protein content, and the outermost is much thinner with low protein content, and strongly reactive to the PAS staining. The spermatozoa are arranged in clusters of 3-4 spermatozoa and immersed in an eosinophilic, and strongly PAS positive secretion. Spermatozoa have many spikes. Although further analyses are necessary, the composition of the spermatophore, and the arrangement and form of the spermatozoa appear to be novelties within Caridea. UBACYT-2014-2017-20020130100186BA, PIP-2015-2017-11220150100544, PICT 2016-0759.Keywords: Neocaridina davidi, male reproductive system, spermatophore, testes, vasa deferentia