Pteraeolidia ianthina
Blue dragon | Blue Dragon Nudibranch
Similar Species
Same Genus
Distribution
Temperate Australasia, Tropical Indo-Pacific
Description
Large nudibranch, easily recognised by the elongate body shape and fans of long cerata down the back. The rhinophores have purple tips and the oral tentacles have two purple bands. When feeding on soft corals, it does not digest the photosynthetic cells (zooxanthellae) embedded in the soft coral tissue, but uses it o harness solar energy and dependant upon the amount of Zooxanthellae of the the animal has in its digestive glands the body colour will range from white to brown. . Similar species Pteraeolidia semperi found in Tropical Indo Pacific has more bands on the rhinophores and has been removed as a synonym of P. ianthina following DNA testing. This is the only nudibranch known with adults that remain beside and protect its eggmass.
Information
Max Size: 15 cm
Sea Temperature Range: 14.1-25.2°C
Depth: 0-27m
Habitat Generalization Index: N/A
Also referred to as the SGI (Species Generalisation Index), this describes the habitat niche breadth of the species. Species with values less than 15 are found in a relatively narrow range of reef habitat types (specialists), while those over 25 may be found on most hard substrates within their range (generalists). Learn more here.
Conservation and Rarity
IUCN Status: Not Evaluated
Occurrence: Infrequent (6.9% of sites)
Occurrence describes how often the species is found on surveys within its distribution. It is calculated as the % of reef sites surveyed by RLS divers across all the ecoregions in which the species has been observed
Abundance: Few (2 per transect)
Abundance is calculated as the average number of individuals recorded per RLS transect, where present.
Edit by: GJ Edgar. 2008. Australian Marine Life. New Holland, Sydney