Effects of salinity on the larval development of the semiterrestrial sesarmid mangrove crab Neosarmatium indicum (A. Milne Edwards) under laboratory conditions

Abstract

The larval development of the semiterrestrial sesarmid mangrove crab Neosarmatium indicum (A. Milne Edwards, 1868) was studied under laboratory conditions at salinities 0-35&&PM and temperatures of 25.5-27.5[degree]C. The larval development consists of five zoeal stages and a megalopa. Larvae survived to the first crab stage at salinities between 5 and 35&&PM with different percentages. At the 0&&PM, the larvae died within 12 hours without moulting to subsequent stages. Total duration of development to the first crab stage was 45, 38, 34, 30, 28, 35 and 40 days at 5, 10, 15, 20, 25, 30 and 35&&PM, respectively. Significant differences (P < 0.05) in the survival rate were found among the tested salinities. The best survival rate for each larval stage was recorded at 20 and 25&&PM.