Eubranchus rubeolus
Burn, 1964

Family: Eubranchidae


Known from a single specimen from Victoria Australia. Possibly ocurs in New Zealand (see discussion below).


Eubranchus rubeolus - original drawing of holotype, 7 mm long alive. Point Lonsdale, Port Phillip Heads, Victoria, Australia. Burn 1964, Fig 6.

This species was described from a single specimen from Victoria, Australia. I have copied below Burn's description of the external features.

Description: The living slug was 7 mm. in length; preserved it is 3 mm. long including the turned up tail. 1,1 mm. wide and 1.1 mm. high. The medianly folded sole is 0.7 mm. wide over the thickened margins, the cerata are up to 1.1 mm. long. Alive the body colour was white with shining yellow edges to the foot and head, the rhinophores and tentacles were dark red except for a subapical yellow band and a white cap, On the notum there were 3 round or elongate dark red patches: 3 patches (Fig. 6m) each side correspond with the spaces between the notal patches plus one below the rhinophores. Cerata heavily pigmented: digestive gland dark red for lower four-fifths, white above: cnidosacs white: the skin over the dark red digestive gland is red, over the white part and above it is pale gold with subepidermal white pigment cells. Preserved the coloration consists of yellow body and yellow capped dark red cerata.

Miller (1971) identified a eubranchid from sthn New Zealand as E. rubeolus but there are considerable differences in colour pattern between the two. An example of the New Zealand 'species' has recently been posted on the Forum [message #16605]. The only specimen known of the Victorian species is the holotype. Until more specimens from New Zealand and Australia are rediscovered it is difficult to know whether the colour differences are within the normal range of variation within one species or whether we have two species.

  • Burn, R.F. (1964)  Descriptions of Australian Eolidacea (Mollusca: Opisthobranchia) 2. The genera Nossis, Eubranchus, Trinchesia, and Toorna. J. Mal. Soc. Aust., 8: 10-22.
  • Miller, M.C. (1971) Aeolid nudibranchs of the family Flabellinidae and Eubranchidae from New Zealand waters. Zoological Journal of the Linnean Society, 50: 311-337.
Authorship details
Rudman, W.B., 2006 (May 15) Eubranchus rubeolus Burn, 1964. [In] Sea Slug Forum. Australian Museum, Sydney. Available from

Related messages

Eubranchus rubeolus? from Fiordland, New Zealand

May 16, 2006
From: Ian Skipworth

Hi Bill

Here's a little aeolid I found recently in Dusky Sound. It's not familiar to me and your comments on its identification would be much appreciated.

Locality: Passge Point, Dusky Sound, 12m, Fiordland, New Zealand, Tasman Sea, 8 May 2006, Rocky reef. Length: 8mm. Photographer: Ian Skipworth.


Skipworth, I.R., 2006 (May 16) Eubranchus rubeolus? from Fiordland, New Zealand. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from

Dear Ian,
Your visit to Fiordland has produced some interesting animals. Michael Miller (1971) describes 4 specimens from Dunedin, in sthn New Zealand, and identified them as Eubranchus rubeolus Burn, 1964 a species from Victoria, Australia. Your animal differs from Miller's in not having any orange on the head, oral tentacles and bottom half of rhinophores, but otherwise they are identical. One important feature to note is the orange patch in the dorsal midline just behind the rhinophores. If you have any other photos it would be nice to know of there are any orange patches or a line on each side of the body, as Miller describes a broad orange band along each side of the body.

What I am not sure is if this is the same as Burn's E. rubeolus from Victoria, a species which is based on a single 7 mm long specimen. As far as I know it has not been reported again in Australia. As I have outlined on the Fact Sheet, there are some colour differences between New Zealand and Victorian animals but until it is redescribed from Victoria, we can't be sure if they are the same species
Best wishes,
Bill Rudman

Rudman, W.B., 2006 (May 16). Comment on Eubranchus rubeolus? from Fiordland, New Zealand by Ian Skipworth. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from