COMMUNITY STRUCTURE AND VERTICAL-DISTRIBUTION OF CYCLOPOID AND POECILOSTOMATOID COPEPODS IN THE RED-SEA .3. REEVALUATION FOR SEPARATING A NEW SPECIES OF ONCAEA

Fine mesh net samples from the upper mesopelagic zone (100 to 450 m) of the central and northern Red Sea during autumn and winter 1980-81 were re-examined to separate the abundance and vertical distribution of 2 very similar small Oncaea species, O. tregoubovi and Oncaea sp. K, which previously had been considered as a single species. O. tregoubovi is more abundant and lives at deeper layers than Oncaea sp. K. The new results alter the ranks of important cyclopoid and poecilostomatoid species in both subzones of the upper mesopelagic zone, although the dominance of O. tregoubovi in the lower part, at 250 to 450 m, still remains very high.