Spottail Grunt, Haemulon maculicauda
The Spottail Grunt, Haemulon maculicauda, whose common Spanish name is burro rasposo and whose local name is roncador, is a species in the Grunt or Haemulidae Family, known collectively as burros in Mexico. Globally, there are tweety-one species in the genus Haemulon, and all twenty-one are found in Mexican waters, fourteen in the Atlantic and seven in the Pacific.
The Spottail Grunts have longer and thinner bodies than most Grunts with a depth that is 32 to 34% of standard length. They have an overall gray appearance and are characterized by a large black spot or blotch at the base of their caudal fin, after which they are named. This fish are abundant in in-shore waters and can also be caught at depths up to 110-feet. We have observed that fish coming out of deeper waters have significantly dark tail spotting than inshore fish (as seen photographically below). Their mouths are oblique, with a red interior, and open below eye level. They have scale rows with white centers that run parallel along their sides giving the appearance of white rows on their sides. Their dorsal fin is continuous with a modest notch in the middle. All their fins are dark. Juveniles have a dark mid-lateral stripe and a black spot at the base of their caudal fin.
The Spottail Grunts are found inshore around coral and rocky reefs at depths up to 110 feet. They reach a maximum of 30 cm (12 inches) in length and 1 kg (2.2 pounds) in weight. They are nocturnal feeders. Very little is known about their behavioral patterns.
In Mexican waters the Spottail 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 Spottail Grunt can be confused with the Latin Grunt, Haemulon steindachneri (yellow fins) and the Mojarra Grunt, Haemulon scudderi (overall gray appearance; no spot on base of caudal fin; yellow fins).
The Spottail Grunts are generally too small and too rare to be of interest to most.
Spottail Grunt, Haemulon maculicauda. Fish caught from coastal waters off Acapulco, Guerrero, February 2017. Length: 25 cm (10 inches). Catch and photo courtesy of Ben Cantrell, Peoria, IL.