Cuthona caerulea is a small aeolid nudibranch found in
shallow water feeding on hydroids. It is reported to feed
on Sertularella hydroids and is easily identified because of
its bold ceratal colouration.
Propodial tentacles: Absent, (foot rounded). Oral tentacles: 2 in number, medium, with yellow tips
and superficial white pigment. Rhinophores: Translucent with yellow tips and
superficial white pigment, smooth. Cerata: Brightly coloured with orange, blue,
yellow/orange areas often with a dark green line between
the blue band, and with white tips. Foot: Translucent without appendages.
Size range: 3-10mm. Fairly common.
Specific characteristics: This species is easily identified
in the field because of its bright colours and the yellow
tipped tentacles.