Growth and maturation of the ghost shrimp Lepidophthalmus sinuensis Lemaitre and Rodrigues, 1991 (Crustacea, Decapada, Callianassidae), a burrowing pest in penaeid shrimp culture ponds

Growth and sexual maturation were studied in the ghost shrimp Lepidophthalm us sinuensis, a pest species infesting oligohaline penaeid shrimp culture p onds on the Caribbean coast of Colombia. Sex ratio was significantly female -biased over four years of sampling. Development of ovaries, indexed as rel ative width, peaked prior to peak occurrence of ovigerous females and eithe r coincided with or immediately followed the quarter of lowest ambient sali nity. Ovigerous females occurred in all months, but the greatest mean perce ntage occurred in the first or second quarter of each year. Size and colora tion of ovaries varied by maturational stage, and monthly counts of eggs pe r female peaked in February-April. Detection of recruits <8-10 mm carapace length (CL) was sporadic, and tracking of growth in recruitment cohorts was not possible. Mean CL of the population increased slowly over the first tw o years of sampling, as the percentage of males in the population increased . Sexual maturity in both males and females was evident in relative growth changes of the major chela. Analysis of growth in chela width, scaled to ca rapace length, suggested that males mature at about 11.0-11.3 mm CL, wherea s females mature near 10.8-11.2 mm CL. Prematuration positive allometric gr owth did not differ between sexes, whereas postmaturation negative allometr ic growth in females differed significantly from strongly positive allometr ic growth in postmaturation males. Relative growth in wet weight of postmat uration males significantly exceeded that of postmaturation females. Expect ed female weight accumulations from episodic ovarian development were perha ps offset by simultaneous negative postmaturation growth of the female majo r chela. An understanding of growth, maturation, and the reproductive cycle of this shrimp species will help develop management strategies to control infestations by this callianassid pest species.