Species by Order: Cyclopoida

Natural History
Oithona nana

Shows strong positive phototaxis.

Oithona setigera

Oithona setigera lacks the tuft of fine hairs on the ventral side of the genital segment that is found in O. plumifera (which also occurs in the San Diego region).

Oithona similis

A 'sit and wait' hunter, they provide few clues (either hydrodynamic or visual) to their presence. In the North Sea O. similis has been shown to have very low mortality rates (Eiane and Ohman 2004), which helps explain why they are so abundant in the ocean.