The Filefish Family – Monacanthidae
The fish of the Filefish or Monacanthidae Family are known in Mexico’s fishing areas as Lijas. There are a total of one hundred eleven global family members that have been placed in twenty-six genera of which eleven species are found Mexican waters, eight in the Atlantic, one in the Pacific, and two in both the Atlantic and the Pacific. They are circumglobal with the majority being found in the cooler waters of temperate and subtropical seas.
The Filefish are relatively small fish; the largest are 1.0 meters (3 feet 3 inches) in length but most are less than 20 cm (7.9 inches) long. They are close relatives of the Triggerfish (Balistidae). They have deep and very compressed bodies that vary in shape from oblong to almost circular. They have a long pointed snout with a concave profile, a small mouth that opens at the front, moderately strong teeth (six in the upper jaw and six or less in the lower jaw), and a gill opening that is a short slit on the side before the pectoral fin base. They have two dorsal spines, the first of which is long and can be locked in place and the second of which is either very small (less than 33% of the length of the first) or non-existent. Their pelvic fins are either absent or reduced to a small scaly spine. Their skin is coarse sandpaper-like. They are covered with small scales.
Filefish are generally pale brown to dark brown with or without paler or darker blotches and/or dark spotting; some species are very colorful with iridescent blue markings. They have the ability to change color to match their surroundings. Filefish are found at depths between 30 feet and 300 feet; they are a benthic species living in and around coral and rocky reefs or on sandy and muddy bottoms and within seagrass beds. They tend to be secretive, often hiding in thick algae, seagrasses, gorgonians or coral. Most are omnivores and feed on a wide variety of benthic animals and plant life including algae and sponges. Some species are schooling but most are found as individuals or in pairs. Larger Filefish are consumed by some human cultures on a limited basis (primarily in Australia), however, most Filefish are considered trash fish obtained in commercial bottom trawls.
Five filefish are currently included in this website, two that reside in both the Atlantic and the Pacific two from the Atlantic and one from the Pacific:
Barred Filefish, Cantherhines dumerilii
Orangespotted Filefish, Cantherhines pullus
Planehead Filefish, Stephanolepis hispidus
Scrawled Filefish, Aluterus scriptus
Unicorn Filefish, Aluterus monoceros