MATING BEHAVIOUR IN THE MARINE ORNAMENTAL SHRIMP Stenopus hispidus

RAFAEL A. GREGATI; VIVIAN FRANSOZO; LAURA LÓPEZ GRECO*; MARIA LUCIA NEGREIROS-FRANSOZO

VERACRUZ, MEXICO

Congreso; WAS AQUACULTURE 2009; 2009

World AQUACULTURE SOCIETY

mating behaviour in THE marine ornamental shrimp Stenopus hispidus Rafael A. Gregati; Vivian Fransozo; Laura López Greco*; Maria Lucia Negreiros-Fransozo *Dept. of Biodiversity and Experimental Biology, FCEyN, University of Buenos Aires Ciudad Univ. C1428EHA, Buenos Aires, Argentina. laura@bg.fcen.uba.ar S. hispidus is one of the most popular decapod with ornamental interest. It is commonly known as “banded coral shrimp” or “clown shrimp”, due to its colorful body. It is collected around the world for aquarium trade purposes and because of its popularity, a number of attempts have been carried out to close its complete life cycle on commercial scale. This species lives in mating pairs when adult and exhibit strongly agonistic behavior with other couples or individuals of the same species, so according to this, the aim of this study was to characterize the mating system and sperm transfer as an important step to complete the life cycle in captivity.         Adults were kept as mating pairs in a recirculation water system, photoperiod 12:12, salinity 35‰ and 26 ± 1°C. They were daily fed with ornamental fish food and pieces of shrimp, squid or shellfish. The reproductive cycle was monitored and the mating behavior was recorded with a video camera. As mating occurs at night, we separated each couple in the same aquarium with a movable plastic net at late afternoon. At morning in the next day if female molted, the net was removed. Mating behavior was observed and described nine times. The behavior of males and females was similar in all events, with variation in the time, from a few minutes up to 6 hours. No courtship display was registered, and the antennule or antenna contact was subtle, differing from previous descriptions. The differences related to the mating time were related to female behavior. Females are not always “receptive” so males spent hours following and encouraging them, tightening her with the two pairs of minor chelipeds (1). When the female is receptive, she shows her pleopods to male while tightening (2); he moves to a perpendicular position (3) and he stays a few seconds abdomen versus abdomen with the female, both moving their pleopods (4). Finally, the male makes a fast spin, and he put his first pleopods against the basis of the female large chelipeds (third pereiopod) where her gonopores open, transferring the spermatophores in a few seconds (5). Spawning was almost immediate, but in a few cases this process delays nearly six hours. No fights or cannibalism were registered, as occurs in other ornamental shrimps of genus Lysmata. Mating behavior of S. hispidus is similar to other caridean shrimp species, where mating occurs soon after the female molts and need to copulate during each reproductive cycle. Financial support: CAPES (fellowship to the first author), CNPq (international cooperation) and FAPESP (installations and vehicles). All the experiments were conducted at the NEBECC (Núcleo de Estudos em Biologia, Ecologia e Cultivo de Crustáceos), UNESP, Botucatu, Brasil.