Reproductive biology of the deep-sea shrimp Heterocarpus chani Li, 2006 (Decapoda: Caridea: Pandalidae) from southern India

The caridean shrimp Heterocarpus chani Li, 2006 (Pandalidae), is widely distributed along the Indian coasts, and is commercially exploited by deep-sea fisheries in southern India. There is limited information on its reproductive biology. A total of 3,122 specimens were collected from commercial bottom trawlers with a 25-30 mm mesh cod-end at depths of 200-300 m between November 2013 and December 2015. There was no significant difference (P < 0.05) in the sex ratio, and size at first maturity with regard to the carapace length was estimated as 22.2 mm in females and 21 mm in males in Arabian Sea specimens and 22 mm and 20.8 mm, respectively, in Bay of Bengal samples. Ovigerous females were observed through the entire fishing season, which indicates year-round breeding, with three stages identified in the development of eggs (early, middle, and late stages). The estimated absolute and relative fecundity in ovigerous females ranged 830-45,650 eggs and 160-2,871 eggs g(-1), respectively. The maximum of 45,650 eggs is the highest number so far reported for any pandalid species. The relationship between carapace length and fecundity revealed b values of 3.31 to 6.33, indicating positive allometry with the coefficient of determination (r(2)) of 0.21-0.37. Knowledge of the reproductive biology of the species can be further extrapolated aiming for the sustainable management of this resource.