Noumea decussata
Risbec, 1928

Order: NUDIBRANCHIA
Suborder: DORIDINA
Family: Chromodorididae

DISTRIBUTION

Tropical West Pacific

PHOTO

on sponge, 70ft, Split Solitary Is, Coffs Harbour, nthn New South Wales, Australia. December 1989. PHOTOS: Carol Buchanan

Mantle white, sometimes with obscure yellow specks. Rhinophore clubs are red and the translucent clear gills have a red line along the inside edge. The mantle has pair of folds about two-thirds of the way down the body, given it a cross-like or cruciform appearance. There has been some confusion between this species and Noumea simplex in the literature, some of it no doubt due to Risbec (1953) misidentifying specimens of Noumea simplex as N. decussata. In Noumea simplex the mantle ranges in colour from pink to white and there is usually an orange-red line, often broken, along the edge of the mantle, and the tips of the gills and rhinophore clubs are bright orange. Compare also with Noumea romeri which also has a pinkish mantle. In that species there is a distinct whitish border to the mantle, the outer edge of the vibratile gills is orange and the upper half of the rhinophore clubs are orange.

See Scott Johnson's observations of N. decussata feeding on a yellow species of aplysillid sponge, and Carol Buchanan's photo here of it on another aplysillid. Both sponges seem different from the bright pink aplysillid sponge which N. simplex and N. romeri are usually associated with.

Authorship details
Rudman, W.B., 2001 (April 13) Noumea decussata Risbec, 1928. [In] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/factsheet/noumdecu

Related messages

  1. Data for Noumea decussata from Japan
    From: Yukari Sato, September 25, 2003
  2. Noumea decussata from Japan
    From: Yukari Sato, September 15, 2003
  3. Noumea decussata clustering
    From: Scott Johnson, August 22, 2001
  4. Noumea decussata from the Marshall Ids
    From: Scott Johnson, April 16, 2001

Show factsheet and all related messages