Family: SCORPAENIDAE, Scorpionfishes
Small to medium sized fishes (to ~ 50 cm); body usually weakly compressed; head relatively large (37-50% of SL) and spiny; a spiny, longitudinal ridge under eye; eye variable in size; snout variable in length; numerous small conical teeth on jaws; teeth present or absent on roof of mouth; preopercular margin with 3-5 spines; 2 (1-2) spines on opercle; a single dorsal fin, usually strongly notched at the rear of the spiny part, VIII-XVIII strong, venomous spines, 4-14 soft rays; anal fin II-IV, 5-14; pelvics I, 5, under pectorals; pectorals large, 11-24; tail fin round to straight; lateral line with 12-54 pored or tubed scales; scales small, smooth or rough, sometimes absent or tiny and imbedded.
Scorpionfishes are bottom living predators that occur in a variety of depths from shallow tide pools to the oceanic abyss. Most reef species are secretive, dwelling in caves and crevices. They usually remain stationary during daylight, but are nocturnally active, feeding mostly on crustaceans and fishes. Scorpaenids often exhibit variegated color patterns that blend well with their surroundings, thus enabling them to remain undetected by their prey. The dorsal, anal, and pelvic spines are all venomous. Poison is produced by glandular tissue in longitudinal grooves on each side of the spine. Wounds from the spines vary from bee-sting intensity to unbelievable agony in Indo-West Pacific genera such as Synanceia (stonefishes) and Pterois. Immersion of the injured limb in very hot water helps alleviate the pain, but treatment by a physician may be required.
Scorpionfishes are found in all temperate and tropical seas and are commercially important in some areas. Most of the estimated nearly 430 species and 67 genera occur in the Indo-Pacific; only a few (12 species from 4 genera; one Indo-Pacific, the rest endemic) are found in shallow areas in our region, but numerous species occur in the adjacent temperate seas, the north and south.