Dendrodoris atromaculata
(Alder & Hancock, 1864)

Order: NUDIBRANCHIA
Suborder: DORIDINA
Superfamily: EUDORIDOIDEA
Family: Dendrodorididae

DISTRIBUTION

Tropical Indo-West Pacific

PHOTO

Upper: Living animal (67 mm long alive) found intertidally at Rowes Bay, Townsville, Australia. B. living animal (37 mm long alive) found intertidally at Nasese, Fiji. Photos: J. Brodie.

Dendrodoris atromaculata is one of the large tuberculate species of the genus, with a relatively high body profile and broad, but firm, mantle skirt,  crawling adults reaching up to 85 mm in length. The dorsum is covered in compound tubercules, each with a narrow stalk and a swollen midsection bearing many finger-like papillae which radiate out in a stellate pattern.

The mantle ranges in colour from pale yellow, to a brownish orange, and there are usually irregularly shaped darker brown to black patches.  The underside usually lacks markings, but specimens can have scattered small black spots (Brodie, 2004) were scattered across the ventral underside of the pale orange notum. The foot is of similar in colour to the dorsal background colour but the colour can be more intense. There can also be brown spots on the sides of the foot.
The rhinophores are relatively small with a translucent orange club and colourless stalk. There are four large and finely branched gills, and they are arranged in a cross.
 
Although described 150 years ago from India, there are very few records of it in the literature.
  • Alder, J. & Hancock, A. (1864) Notice of a collection of nudibranchiate mollusca made in India by Walter Elliot Esq., with descriptions of several new genera and species. Transactions of the Zoological Society of London, 5: 113-147.
  • Brodie, G. D. (2004) An unusual dendrodorid: redescription of the tropical nudibranch Dendrodoris atromaculata (Alder & Hancock, 1864) (Anthobranchia: Doridoidea: Dendrodorididae). Zootaxa, 503: 1-13.
Authorship details
Rudman, W.B., 2007 (August 28) Dendrodoris atromaculata (Alder & Hancock, 1864) . [In] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/dendatro

Related messages


Dendrodoris atromaculata? from Western Australia

August 29, 2007
From: Bruce Potter

Dear Bill,
I found this critter under a jetty last weekend and have not been able to identify it at all. I found it quite difficult to photograph because of its colour and texture, all the shots turned out like poor quality paintings instead of high quality photos.

Locality: Rockingham, 6 metres, Western Australia, Indian Ocean, 11 August 2007, Mucky under Jetty. Length: 30 mm. Photographer: Bruce Potter.

Regards
Bruce Potter.

bandppotter@bigpond.com

Potter, B., 2007 (Aug 29) Dendrodoris atromaculata? from Western Australia. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/20476

Dear Bruce,
I can understand your problems - the tubercles on its mantle fall into two size categories and their colours make them merge into the background. When I first saw your photo my immediate thought was Hoplodoris estrelyado but on a closer look, the tubercles are quite different. Some are relatively short and tapering while others have a narrow stalk and then enlarge to a large multituberculate club, with a tapering flagellum at the tip.

I suspect this is Dendrodoris atromaculata, but as you will see in the Fact Sheet photos kindly provided by Gilianne Brodie, that species is usually a yellowish colour with large black patches. However the tubercles are so distinctive that I suspect your animal is a colour form. Without any information on its anatomy I could of course be quiet wrong. This is another example where a photo of the underside and the area around the mouth would have been very useful, because the head of a dendrodorid is very distinctive.  

Best wishes,
Bill Rudman

Rudman, W.B., 2007 (Aug 29). Comment on Dendrodoris atromaculata? from Western Australia by Bruce Potter. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/20476