Genus Archocentrus Gill

Heros (Archocentrus) Gill in Gill & Bransford, 1877: 185 ^ZBK (original description as subgenus).

Herotilapia Pellegrin, 1904: 211 ^ZBK (junior synonym).

Cichlosoma, “section” Archocentrus, Regan 1905: 74 ( new combination).

Archocentrus, Allgayer 1994: 13 ( new status).

Type species. Heros (Archocentrus) centrarchus Gill, 1877 ^ZBK, by monotypy.

Diagnosis. Genus distinguished by three strict synapomorphies (Schmitter-Soto, in press). Anal pterygiophores on first haemal spine usually five, anal-fin spines modally 11-12, genital papilla oval, the opening strongly crenulated or deeply notched; notch not rounded. Further diagnosed from similar genera by a concave posterior end of maxilla, except in Archocentrus centrarchus, and peritoneum moderately pigmented dorsolaterally (also in Cryptoheros ^ZBK, Petenia ^ZBK, and Amatitlania kanna). Two interorbital bands (also in Rocio).

Description. D. XVI-XIX,7-10; A. X-XIII,7-9; scale rows on cheek 4-6; pored lateral-line scales 25- 29; predorsal scales 12-17; scales from vent to interpelvic scale 6-9; circumpeduncular scales 15-21; anal creases 10-15. Species small, less than 110 mm SL. Body rather oval, deep, depth 47-61% of SL. Head length 33 -35% of SL. Snout short, length about 25% of head length. Orbital diameter 24-33% of head length. Caudal peduncle twice as deep as long; least depth 16-19% of SL. Head profile straight or concave to above orbits, convex at nape. Lips not medially narrow; pectoral and pelvic fins long, always reaching posteriorly to, or beyond, 3rd anal-fin spine. Origin of pelvic fin posterior to a vertical from origin of dorsal fin. Gut equal or longer than body. Seven vertical bars on side of body; dorsal and anal fins immaculate or with dots in a checkered or diagonally-aligned pattern. A blotch on scaly base of caudal fin, which crosses lateral line, ocellated or not.

Distribution. Pacific slope of Central America from Costa Rica ( Río Tempisque) to Nicaragua ( Río Guasaule); Atlantic slope from Costa Rica ( Río Matina) through the Great Lakes of Nicaragua to Guatemala (tributaries of Lago Izabal) (Fig. 1).

Species composition. Archocentrus as restricted here includes only three species: Ar. centrarchus, Ar. multispinosus, and Ar. spinosissimus .

Remarks. The synonymization of Herotilapia ^ZBK is discussed and justified below.