Whitespotted Filefish, Cantherhines macrocerus

Whitespotted Filefish, Cantherhines macrocerus. Fish caught from coastal waters off Broward County, Florida, June 2023.  Length: 40 cm (16 inches). Catch, photograph and identification courtesy of Dominick Porcelli, Lighthouse Point, Florida.

The Whitespotted Filefish, Cantherhines macrocerus, is a member of the Filefish or Monacanthidae Family, and is known in Mexico as lija de lunares blancos. Globally, there are twelve species in the genus Cantherhines, of which three are found in Mexican waters, two in the Atlantic and one in the Pacific Ocean.

The Whitespotted Filefish has a deep oblong compressed body that are 63% to 67% of standard length. They are an overall dark brown color or mixtures of brown and orange and they are covered with pales spots with a indistinct prominent pair of spots at the top and bottom at the caudal base.  The spines on the caudal base are yellow. The caudal fin, first dorsal fin and pelvic fins are brown; the anal fin and second dorsal fin area transparent. The juveniles are black with many white spots.  The head has a long pointed snout and a small mouth that opens at the front that is equipped with six strong teeth on the upper jaw and six or less on the lower jaw.  Their short gill slit is on the side before the pectoral fin base. They are sexually dimorphic with the males  having larger spines on the caudal peduncle and an orange patch anterior to the peduncle spines. Their anal fin has 29 to 32 rays; their caudal fin in rounded; their first dorsal fin is set toward the front of the  head and has two spines, the second dorsal fin at 34 to 36 rays; their pectoral fins have 14 rays. They have rough skin, are covered with minute scales and have an inconspicuous lateral line.

The Whitespotted Filefish is found in pairs at depts up to 93 m (300 feet) within coral reefs and rocky bottoms within gorgonian corals. They reach a maximum of 40 cm (16 inches) in length. They are similar in appearance to triggerfish and are capable of locking their their first dorsal spine in place. They consume algae, gorgonians, hydroids, sponges and stinging coral. The Whitespotted Filefish is poorly studied with very limited information available about their lifestyle and behavioral patterns including specific details on age, growth, longevity, movement patterns, diet, habitat use, and reproduction.

In Mexican the Whitespotted Filefish is found in the southern portions of the Sea of Cortez and along the east coast of the Yucatán Peninsula in the Caribbean.

The Whitespotted Filefish is easy to identify due to white spotting pattern that cover the body. However, they have similar body profiles to five other filefish found in Mexican waters.

From a conservation perspective the Whitespotted Filefish is currently considered to be of Least Concern with stable, widely distributed populations.