Raucous Grunt, Haemulopsis leuciscus
The Raucous Grunt, Haemulopsis leuciscus, whose common Spanish name is ronco ruco, and whose local name is roncador, is a member of the Grunt or Haemulidae Family, known collectively as burros and roncos in Mexico. There are only five global members of the Haemulopsis Genus of which four are found in Mexican waters, all in the Pacific.
The Raucous Grunts have oblong bodies with a depth that is 32 to 34% of standard length. They have an overall silver appearance and a straight ventral profile. Their head features an apparent “bump” above their eyes. They have a short snout (11 to 12% of standard length) and their mouth ends before their eyes. The outside edge of their upper gill cover and their pectoral fin base are black. Their second anal spine is stout and longer than the eye diameter and their pectoral fins are short. Their fins are dusky with the exception of their pelvic fins, which are yellow.
The Raucous Grunts are found over sandy and muddy bottoms at depths up to 440 feet. They reach a maximum length of 41 cm (16 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 Raucous Grunts are found in all waters of the Pacific with the exception that they are absent from Magdalena Bay northward along the central and northwest coasts of Baja.
The Raucous Grunt is difficult to identify as it is very similar in appearance to the Elongate Grunt, Haemulopsis elongatus (straight head profile, snout 10 to 11% of standard length), the Shining Grunt, Haemulopsis nitidus (very short second anal spine; black blotch behind operculum) and the Yellowstripe Grunt, Haemulopsis axillaris (third anal spine longer than second; snout 6 to 7% of standard length).
The Raucous Grunts are not abundant or of significant interest but are viewed as good table fare when available. They are caught primarily off the beach during the warm water months.