Argestidae Por, 1986 (Copepoda: Harpacticoida) are one of the most abundant taxa in muddy sediments of the deep oceans. This family with up to date 20 known genera and 83 described species shows well visible morphological characters, allowing quick identification not only at family level, but also at generic and even species level. Altogether, their high abundances, their frequent occurrence in deep-sea samples all over the world, combined with their high recognition value, Argestidae are supposed to be excellent representatives for chorological and biogeographical studies of Harpacticoida the deep oceans. During DIVA 1 expedition of RV METEOR (July/August 2000), two stations at the Angola Basin were sampled quantitatively. As first analyses show, both stations differ remarkably regarding their taxa composition. During DIVA 2 cruise of RV METEOR (February/March 2005), the Cape Basin, Angola Basin, and Guinea Basin were sampled. First results indicate that both Cape and Guinea Basin show considerable similarity considering species occurrence but differ remarkably from the Angola Basin. Since the Angola Basin is geographically positioned between the Cape and Guinea Basin, the obtained results indicate, that other factors than geographic structures seem to rule the occurrence of benthonic living harpacticoid copepods in the deep oceans.