See Korshunova et al 2020.
Synonyms: Eolis pallida Alder & Hancock, 1842; Eolis picta Alder & Hancock, 1847;
Body (excluding appendages)
Length up to 23mm. Translucent white with rich mahogany pigment flecks that usually coalesce on dorsum [image 1]. Sometimes, also white and gold flecks, but no greenish ones.
Arranged in up to ten groups along each side. Up to seven inflated cerata in each group, the dorsal ones larger than the peripheral. Translucent white revealing brown or pale-brown internal digestive gland. Flecks of mahogany and white surface pigment. Distally white with sub-apical gold ring.
Twice as long as oral tentacles. Smooth, translucent white with mahogany flecks basally and mahogany band two-thirds of way up. Also white pigment freckles.
Dorsally, white, with mahogany flecks and some white flecks spreading onto it from oral tentacles. Small black eyes set back from rhinophores . Oral tentacles translucent white with mahogany flecks and band half way up, also freckles of white pigment. Ventrally, large cylindrical mouth, slit ventrally .
Widest at anterior , but no propodial extension or tentacles. Tapers gradually to posterior.Sole translucent white.
Key identification features
Inflated smooth cerata distally white with sub-apical gold ring.
Mahogany and white pigment marks on body, never greenish.
Basal mahogany mottling on white translucent rhinophores and oral tentacles .
Band of mahogany two-thirds way up rhinophores and half way up oral tentacles.
Cerata smooth, changeable, but always at least moderately inflated.
Usually orange pigment blotches on body.
Usually orange subterminal band on cerata.
Rhinophores and oral tentacles, part or completely orange.
Cerata smooth, like flattened rugby balls.
Dorsum concealed by crowded cerata (up to 150).
Body pale yellow or greyish white.
Subterminal golden-yellow and white bands on cerata.
Inside cerata; indistinct red-brown digestive gland often tinged violet distally.
Rhinophores and oral tentacles; pale yellow-brown with paler tips.
Ecology and behaviour
Low water spring tides and sublittorally to 60m. Eats a range of hydroids, including Obelia geniculata (EML) Simultaneous hermaphrodite. Spawn  a spiral ribbon attached by its edge to substrate, recorded in May and July. Several generations p.a.
Distribution and status
References and links
Alder, J. & Hancock, A. 1845-1855. A monograph of the British nudibranchiate mollusca. London, Ray Society.
Thompson, T.E. & Brown, G.H. 1984. Biology of opisthobranch molluscs 2. London, Ray Society.
Current taxonomy; World Register of Marine Species (WoRMS)
The map provided here shows the distribution of the species based on Conchological Society data.