Dendronotus iris

The Rainbow Tree-backed Nudibranch

Phylum Mollusca
Class Gastropoda
Subclass Opisthobranchia
Order Nudibranchia
Suborder Dendronotoida
Family Dendronotidae
Genus Dendronotus
Species iris

Description: Can reach length of 20 cm; white or grayish body but can also be orange to red; dark brownish-red cerata with white tips; a white line runs along the foot; branchial plume or gill tufts may be tipped with yellow, orange or purple; body cylinder shaped, 6 to 9 pairs of elaborately branched cerata with sharp tips.

Habitat: Found on floats and pilings, as well as on rocks near the low tide level.

Natural History: Though usually found in deeper water, this nudibranch can be found at the end of summer, in large numbers near the surface. It is an active swimmer, which feeds upon hydroids, anemones, and the scyphistomae form of jellyfish. This nudibranch detects its food using its chemoreceptors. When it locates its meal, it aligns its mouth towards the tentacles of its prey. Then raising and waving its head it lunges forward biting and striking its prey.