Humpback Grunt

Humpback Grunt, Orthopristis chalceus

The Humpback Grunt, Orthopristis chalceus, whose common Spanish name is burrito corcovado, is a species in the Grunt or Haemulidae Family, known collectively as burros and roncos in Mexico. Globally, there are only eight species in the genus Orthopristis, three of which are found in Mexican waters, one in the Atlantic and two in the Pacific.

The Humpback Grunts have elongated elliptical deep bodies with a depth that is 42 to 45% of standard length. They have an overall silvery-gray appearance changing to white ventrally with oblique orange bands along the scale rows and above the lateral line. The top and bottom head profiles are similar; they have a short snout that ends before their eyes and finely serrated preopercle. Their second anal spine is thick, longer than the third, and about one-half the length of the first anal ray. Their pectoral fins are long and curved. All their fins are translucent except for their caudal fin, which is black.

The Humpback Grunts are found over sandy and muddy bottoms at depths up to 330 feet. They reach a maximum length of 45 cm (18 inches). They are nocturnal carnivores feeding on benthic crustaceans, mollusks, echinoderms, and small fish. They are a poorly studied species and little is known about their behavioral patterns.

In Mexican waters the Humpback Grunts are found from Magdalena Bay southward along the southwest coast of Baja, throughout the Sea of Cortez, and along the coast of the mainland south to Guatemala.

The Humpback Grunt can be confused with the Bronzestriped Grunt, Orthopristis reddingi (elongated body; depth 32-34% of standard length).

The Humpback Grunts are too rare and too small to be of interest to most.

Humpback Grunt, Orthopristis chalceus. Fish caught from coastal waters off Mazatlán, Sinaloa, April 2015. Length: 14 cm (5.5 inches). Catch, photo and identification courtesy of Josh Leisen (lifelistfishing.com), Gaylord, MI.

Humpback Grunt, Orthopristis chalceus. Fish caught from coastal waters off Mazatlán, Sinaloa, April 2015. Length: 25 cm (9.8 inches). Catch and photo courtesy of George Brinkman, Guelph, Ontario, Canada.

Humpback Grunt, Orthopristis chalceus. Fish caught from coastal waters off Mazatlán, Sinaloa, April 2015. Length: 28 cm (11 inches). Catch and photo courtesy of Michael Verdirame, Markham, Ontario, Canada.