Halichoeres nicholsiSpinster wrasse
Tropical Eastern Pacific
Males blue-green with narrow vertical light streaks on each scale, a yellow blotch on fore body, followed by a broad dark band which is in turn followed by a diffuse light band. Head mildly pointed, with blue spots on upper head, lower head unmarked, and dorsal, anal and tail fins with blue spots and dashes. Females pinkish to grey with a dark stripe along body broken on fore-body and joined by an upside down triangular mark on back. Tail fin and underside yellow. Hides under sand to sleep, and shelter from danger.
Max Size: 38 cm
Sea Temperature Range: 20.7-30.3°C
Habitat Generalization Index: 21.69
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: Least Concern
Occurrence: Common (43.2% 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: Joe Shields