Aspects of the life history and seasonal ecology of Nasima dotilliformis (Alcock) (Brachyura: Ocypodidae) on a Kuwait mudflat

摘要

Data on Nasima dotilliformis, between MHWS and MHWN in Sulaibikhat Bay, Kuwait were obtained by sampling every six weeks between May 1988 and March 1989, and from two additional collections. Carapace width frequency data suggested that in females instar number was variable, or fixed with widely overlapping size ranges, and that in males there were instars at 4.75, 7.25 and 9.25 mm. The puberty moult was 4.75-7.25 mm in males and a proportion of females, and sex ratios in all size classes did not differ significantly from 1:1. The chela propodus grew isometrically in both sexes, and growth of the abdomen was negatively allometric in males and positive in immature and isometric in mature females. In both sexes the meri of the third and fourth ambulatories grew with positive allometry in width and length, and the level of growth of the male fourth merus was significantly greater than that of either females or the third merus. Population density, biomass and the percentages of juveniles and ovigerous females were higher in winter (November-March) than summer. Winter was therefore the ecologically-active season, contrary to the cycle normally associated with waters of similar latitude.