ROBOASTRA ARIKA BURN, 1967

(FIG. 8A)

Remarks: Burn (1967) described a new species, R. arika, from Lowe Howe Island, more than 600 km from the east coast of Australia. The description was based on a single preserved specimen, 12 mm long, deposited in the Australian Museum. However, it appears that the holotype has been lost (Rudman, pers. comm.). The only available information about this species stems from the original description. Comparison of the drawing of the half row of radula (Fig. 8A) from Burn (1967) with that of the radula (Fig. 8B) of R. luteolineata from Baba (1936) reveals that they appear to be very similar. Since we do not have any more information, and as we are not sure that both are the same species, we nominate R. arika as a taxon dubium. It is important to emphasize that, in the last few years, pictures of a nudibranch incorrectly identified as R. arika have appeared in a number of popular books (Gosliner et al., 1996; Debelius, 1998; Coleman, 2001) and web pages (www.seaslug forum.net, www.medslug.de, www.aqualife.com, etc.). These pictures are from an unknown species of Tambja, which is currently being described.