Comprehensive DescriptionRead full entry
| Common names: halfmoon (English), chopa (Espanol) |
Medialuna californiensis (Steindachner, 1876)
Body an elongate oval, compressed; small pointed head; mouth is small, horizontal and opens at the front; the top jawbone slips partially under the under-eye bone when the mouth is closed; teeth pointed, 1 row on each jaw; dorsal fin continuous, IX-XI spines that fold down into a scaly groove, 22-27 rays, spiny part much lower than soft part; anal III, 17-21; tail fin slightly concave; paired fins are relatively short; origin of the pelvics behind the base of the pectoral fin; scales small, thick and rough, covering the body, head (except forward of eyes) and soft portions of the median fins.
Dark bluish above, paler below; sometimes indistinct short bars along flank; a dark blotch at upper corner of operculum; dorsal, tail and anal grey, dark outer margins; juveniles blue above, silvery below.
Size: 48.3 cm.
Habitat: rocky bottoms and algal beds.
Depth: 0-44 m.
Canada to the SW Gulf of California.