Morphological characteristics and distribution of Ocypodidae at zoea one larvae stage from coastal waters of Khuzestan Province, Persian Gulf

Taxonomic studies on the Brachyura larvae of the Persian Gulf are relatively few. Samples were collected monthly with a 300μ mesh size plankton net from coastal waters of Khuzestan (Northern Persian Gulf) during May 2007 to April 2008. The stage one zoea larva of 8 species Macrophthalmus depressus, Serenella leachii, Ilyoplax frater, Tylodiplax indica, Dotilla blanfordi, Dotilla sulcata, Uca annulipes and Scopimera crabricauda of Ocypodidae were illustrated and described in detail. Common morphological characteristics in identified species of Ocypodidae are dorsolateral processes on second and third abdominal segments and also two aesthetasc on antennules. Spatial and temporal variations in density of larval stages of Ocypodidae were studied. In warmer months Macrophthalmus depressus larvae (1264 ind/m3 in March, in other warm months (May, June, August and September 2007) M. depressus larvae with average of 97, 168, 87, 318 and 1264ind/m3, respectively were the dominant species agagin and Ilyoplax frater larvae (457ind/m3) in July 2007 were the dominant species. However, in colder months (November and February 2008), Camptandrium sp1 larvae was dominant with 76 ind/m3 and 56 ind/m3 for the two months, respectively.