Armed Grunt

Armed Grunt, Conodon serrifer

Armed Grunt, Conodon serrifer. Fish caught within Magdalena Bay, Baja California Sur, October 2018. Length: 19.7 cm (7.8 inches).

Armed Grunt, Conodon serrifer. Fish caught from coastal waters off Mazatlán, Sinaloa, April 2013. Length: 25 cm (10 inches). Catch, photograph and identification courtesy of George Brinkman, Guelph, Ontario, Canada.

The Armed Grunt, Conodon serrifer, is a member of the Grunt or Haemulidae Family, that is also known as the Serrated Grunt and in Mexico as ronco ofensivo. Globally, there are three species in the genus Conodon, of which two are found in Mexican waters, one in the Atlantic and one in the Pacific Ocean.

The Armed Grunt has an elongated compressed body with a depth that is 26% to 30% of standard length. They have an overall silvery blue gray coloration with brown tinges dorsally and are white ventrally. Their head is silvery brown. They have 6 or 7 bars on their upper sides that do not extend below their pectoral fins. All their fins are yellow with the exception of their first dorsal fin which is dusky. Their eyes are larger than their snout. Their snout has 4 pores, 2 in front and 2 in back. Their gill covers border is concave and strongly serrated with 1 or 2 large spines pointing backwards (after which they are named). Their anal fin has 3 spines, the second being much larger than the third, and 7 or 8 rays; their caudal fin is straight or slightly concave; their dorsal fin has 12 spines and 12 or 13 rays; and, their pectoral fins are long and reach past the pelvic fin tips. Their body is covered with scales.

The Armed Grunts are found at depths between 6 m (20 feet) and 72 m (235 feet). They reach a maximum of 30 cm (12 inches) in length. The Armed Grunt 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.

The Armed Grunt is a resident of all Mexican waters of the Pacific with the exception that they are absent from of the northern third of the Sea of Cortez.

Due to its coloration and marking the Armed Grunt is a fairly easy fish to identify and cannot be confused with any other species.

From a conservation perspective the Armed Grunt is currently considered to be of Least Concern with stable, widely distributed populations. They are small in stature and of limited interest to most. Caution: as indicated by its common name this fish is dangerous to handle, being well protected by numerous spines.