The Sandperches family consists of 82 species grouped into 7 genera. They are exclusively marine fish, present in the South American coasts of the Atlantic and Indo-Pacific Oceans (from New Zealand to Hawaii, being absent in the Chilean coast). The body of the Sandperches is moderately elongated and slightly compressed. Their lateral line is complete and slightly arched in the region of the pectoral fins. They have a pointed head in which the eyes adopt a slightly dorsolateral position. With a relatively large mouth, it is situated in a terminal position and is protractile. The lower jaw usually slightly exceeds the upper jaw. Both jaws have curved teeth located in several rows, with the outer row being larger. The operculum has a very sharp spine at the back of the operculum.
The radial formula of the Sandperches is 1D. IV-VII + 19-24; 1A. I + 16-25; V. I + 5; P. 14-21. That is, they have a single dorsal fin (1D) which is continuous and has between 4 and 7 spines and 19-24 radii. Generally, the portion of the spokes is higher than the spinous portion of the dorsal fin. As for the anal fin (1A), it is unique and has 1 spine and 16-25 spokes. The pelvic or ventral fins (V) have 1 spine and 5 spokes and are located below or slightly forward of the pectoral fins. Usually the fourth radius of the pelvic fins is the longest. The pectoral fins (P) have between 14 and 21 spokes. Finally, the caudal fin is variable in shape depending on the species and can take a shape from slightly rounded to moonlit. It generally has 15 branched spokes, although the range is between 13 and 15 spokes.
Most Sandperches have a distinctive coloration, in which the presence of bright colors is rare. Moreover, most species present sexual dimorphism, so differentiating between male and female individuals is possible. While this is true, it must also be said that these differences can be very subtle. Very territorial in habit, they are usually species that inhabit the seabed, where they feed on small fish and invertebrates.
