Reproduction and growth of the caridean hinge beak shrimp, Rhynchocinetes uritai (Kubo, 1942) (Caridea, Rhynchocinetidae) from the East Sea of Korea.

Abstract

Abstract Biological knowledge of the hinge beak shrimp, Rhynchocinetes uritai in Korean waters is scarce. The objective of this work is to provide the information on size structure, size at maturity and growth of the hinge beak shrimp. We registered 1787 into two consecutive sampling seasons (2012-2013), ratio of females to males was significantly greater ratio 1: 0.25, with predominance of females on larger class sizes, using natural log transformed cephalothorax length-wet weight (LWR) relationships estimated were lnBW = 2.4063 lnCL -5.6628 and lnBw = 2.417lnCL -5.7675 for females and males respectively. The gonadosomatic index (GSI) varied monthly with maximum in September (5.12) and minimum April 2013 (0), the highest values of the GSI coincide with the breeding period, there was significant difference between the mean GSI of females with non-eyed and eyed egg, indicating R. uritai is a consecutive breeder. There was no significant difference in the slope of the regressions of number of egg versus carapace length between females carrying non-eyed and eyed egg stages (F = 0.4, P>0.05) whereas there was a significant difference in intercepts (F = 24.16, P< 0.05), indicating there was brood loos between the two egg stages. Egg volume increased 90% as eggs developed from non-eyed to eyed stage. Based on dry weight in early stages, reproductive output was determined as 0.22±0.016. mean size at sexual maturity of females was CL50 = 8.45 mm. the von Bertalanffy growth parameters were L∞ =14.89mm, C = 0.2, WP = 0.25, φ' = 2.01 for males and L∞ = 21.43mm, C = 0.7, WP = 0.65, φ' = 2.15 for females.