Phyllacanthus parvispinusEastern slate-pencil urchin
Solid dark-purple urchin with large rounded primary spines, which are usually eroded. Like Goniocidaris tubaria, the secondary spines are flat and most obvious around the base of the larger spines. The species uses its blunt primary spines to wedge rigidly into crevices during the day and thus can survive in areas with heavy wave action. It feeds at night on encrusting plants and animals scraped from the reef surface.
Max Size: 9 cm
Sea Temperature Range: 15.3-25.2°C
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: Common (34.9% 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 (5 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