Effects of salinity and starvation on the larval development of Sesarma curacaoense de Man, 1892, a Mangrove crab with abbreviated development
Schuh, M.; Diesel, R.
Journal of Crustacean Biology 15(4): 645-654
1995
ISSN/ISBN: 0278-0372 DOI: 10.2307/1548813
Accession: 031180348
The ecology and development of the mangrove crab Sesarma cuaracoense was studied in Jamaica. Salinity and temperature were measured in the natural habitat of this crab, and the effects of various salinities, different temperatures, and starvation regimes were studied in the laboratory. The crab inhabits mangrove swamps where salinity and temperature ranged from 8-45 ppt and 22.2-39.0 degree C, respectively, and its larval stages were found in the mangrove area and in an offshore lagoon. Females produced relatively few (112-980) moderately sized eggs (mean diameter = 0.58 mm after spawning). Development was abbreviated and consisted of 2 swimming, morphologically advanced zoeal stages and 1 megalopa, and the first crab was reached after an average of 13.5-19.3 days when larvae were fed. Development to the first crab stage was completed at salinities ranging from 10-55 ppt. However, a high mortality appeared at the extremes of 10 and 55 ppt. When starved from hatching, yolk reserves were sufficient for development to the megalopa stage, during which food was required in order to molt to the first crab. Sesarma curacaoense had fewer larval stages, the larvae tolerated a wider range of salinities for development, and showed a higher degree of lecithotrophy than reported for other species of Sesarma outside Jamaica. Its mode of development is similar to that in the endemic Jamaican species (2 zoeae), and its degree of lecithotrophy is intermediate between its semi-terrestrial and truly fresh-water and terrestrial relatives.