Clio pyramidata
Distribution:
Worldwide in warm waters of the Atlantic, Indian and Pacific. In the North Pacific it ranges from Washington to Baja California (more common in the southern region).
Habitat:
Epipelagic to mesopelagic.
Size:
Up to 9 mm
Diet:
Phytoplankton, protozoa, juvenile copepods, nauplii, tintinnids, radiolarians, and centrics diatoms have been found in the gut.
Predators:
The squid Doryteuthis opalescens; also an important food for fish and whales.
Useful Facts or Characters:
Elongate, pyramid-shaped, and transparent shell. Has a pronounced central midrib on the dorsal surface. Shell opening unobstructed; bears a posterior tip. The shell lacks transverse folds and does not curve dorsally.
Natural History:
Known to be an intermediate host for parasitic copepods that eventually infest fish. Several forms exist within the California Current, but here no attempt was made to distinguish them.