Fecundity and brood biomass investment in the estuarine crab Chasmagnathus granulata. (Decapoda, Brachyura, Grapsidae).

STELLA, V.S.; LÓPEZ LAURA S. Y E. M. RODRÍGUEZ.

CRUSTACEANA

E. J. BRILL

Lugar: LEIDEN; Año: 1996 vol. 69 p. 306 - 312

0011-216X

Number of brooded eggs and wet and dry brood weights were measured in the estuarine crab, Chasmagnathus granulatus. Best correlations for all reproductive variables were found with respect to female wet body weight, but while the best fitted model was logarithmic for broods having uneyed embryos (UE), a linear model corresponded to eyed embryo (EE) broods. For UE, larger females invested in each brooded egg 8.4% more of dry biomass than smaller females, in accordance with the logarithmic model adjusted. Overall fecundaity was estimated in 26790 ± 9936 eggs/brood/female. Biomass investment in reproduction was estimated in 7.1% (dry weight basis) and 9.3 (wet weight basis). Egg dry weight decreased throughout embryonic development, in accordance with metabolic requirements of embryos, while a higher water content was noted in EE, probably related to tissue solvation during development and/or increase of the osmotic pressure needed for hatching.