FIRST REPORT OF THE ATHECATE, CHAIN FORMING DINOFLAGELLATE COCHLODINIUM FULVESCENS (GYMNODINIALES) FROM PAKISTAN

A harmful dinoflagellate Cochlodinium fulvescens is reported for the first time from northern boarding of Arabian Sea, Karachi, Pakistan. During a phytoplankton monitoring program between May 2002-July 2003, Cochlodinium was observed from two localities of Manora Channel. Highest abundance was recorded during October 2002 at 926 cells l(-1) during a period of high temperature and high salinity value. Taxonomical characters were studied by using light microscopy, epiflouresence microscopy and scanning electron microscopy. Identification of Cochlodinium fulvescens was confirmed by the presence of granular shaped chloroplast, different cell structure, large size, and intermediate position of sulcus between the cingulum and degree of torsion makes more than 1.5 turns. Emergence of the C. fulvescens in northern Arabian Sea has great concern from a fisheries viewpoint since this species has been implicated in considerable economic losses worldwide.