Author: Undescribed

Order: Nudibranchia  Family: Aegiridae

Maximum Size: 15 mm

Sightings: Sunshine Coast

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Aegires sp. 01 Undescribed

At first glance this species could be easily mistaken for Aegires citrinus, apart from the pure white colour. However, closer examination reveals some black markings anterior and posterior to the gill. Aegires citrinus is known to be yellow and lacking in any kind of black markings. Aegires citrinus also bears a surface patterning that mimics the surface of its sponge prey, that this species lacks.

Rudman discusses Aegires citrinus (then called Notodoris citrina) on the Sea Slug Forum stating: “Adult animals are uniformly yellow and can be distinguished from other species of the genus by their lack of black pigmentation,….” and in another message: “….the pattern on the skin matches the spicular skeleton of the sponge both in size and arrangement.”

Interestingly if we also look at Rudman’s Sea Slug Forum comments on Notodoris sp. 2 (from South Africa) the top image on Message # 1 is a very good match for the specimen in our image above. In Message # 2 he comments: “It is possibly an ‘albino’ form of one of the known species,….” but then finishes with: “At present I think it is probably an unnamed species which we should distinguish as Notodoris sp. 2.”

In consideration of the above we have decided to keep this specimen as a separate species until such time as further evidence may prove it to be otherwise.

David A. Mullins – June 2021

References:

– Rudman, W. B., (2003, July 11) Notodoris citrina Bergh, 1875. [In] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/factsheet/notocitr and associated messages.

– Rudman, W. B., (2009, October 2) Notodoris sp. 2 [In] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/factsheet/notosp2 and associated messages.