Community structure and vertical distribution of cyclopoid and poecilostomatoid copepods in the Red Sea. III. Re-evaluation for separating a new species of Oncaea

Abstract

Fine mesh net samples from the upper mesopelagic zone (100-450 m) of the C and N Red Sea during autumn and winter 1980-81 were re-examined to separate the abundance and vertical distribution of two very similar small Oncaea species, previously 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 peocilostomatoid species in both subzones of the upper mesopelagic zone, although the dominance of O. tregoubovi in the lower part, at 250-450 m, still remains very high. -from Author