Cratena peregrina is a medium sized aeolid nudibranch
often found roaming on hydroids (Eudendrium sp.) in
areas with constant water currents. It is a common
species and easily seen in the field, its bright colours
giving it away. It is often accompanied with Flabellina
affinis, with which it may compete for food.
Propodial tentacles: Present, white in colour. Oral tentacles: 2 in number, very long, tapering and
recurved (like elephant tusks), white in colour. Rhinophores: Long, smooth, almost transparent base
with bright yellow to orange pigment at the upper area. Cerata: Very long and thin, bright red with a purplish
subterminal ring and a white tip. Body: Aeoliid like, base colour is white with two
characteristic bright yellow spots in the area between
the oral tentacles and rhinophores. Foot: White in colour without appendages.
Size range: 15-42mm. Common.
Specific characteristics: This species is easily identified
in the field by the bright red cerata, yellow tipped
rhinophores and the two yellow rectangular spots on the
anterior dorsal area.