Description
The cerata are arranged in 4 to 8 groups. The oral tentacles and rhinophores are very long and the rhinophores are smooth. It feeds on several species of hydroids, but it seems to prefer Tubularia indivisa.

Size
The maximum length is about 55 mm.

Colour
Translucent white to yellowish body, with white pigmentation. The cerata are translucent so the digestive gland is clearly visible and the tips are white. Oral tentacles and rhinophores have white pigmentation as well.

Habitat
In the sub littoral zone.

Distribution
North Atlantic and western Mediterranean.