Some twenty species are known from the fresh waters of Tropical America, A. bimaculata being one of the most common fishes of that region. All are very small.
Heros.—Differing from Acara in having more than four anal spines.
Some fifty species are known from the fresh waters of Tropical America, especially Central America, where almost every large lake or river is tenanted by one or more peculiar species. They are of rather small size, rarely exceeding a length of twelve inches.
Fig. 245.—Heros salvini, from Central America.
Genera allied to Heros, and likewise from Tropical America, are Neetroplus, Mesonauta, Petenia, Uaru, and Hygrogonus.
Cichla.—Form of the body perch-like. Scales small; the spinous and soft portions of the dorsal fin of nearly equal extent, and separated by a notch; anal spines three. Each jaw with a broad band of villiform teeth. The outer branchial arch with lanceolate crenulated prominences along its concave side. Dorsal and anal fins scaly.
Four species from Brazil, Guyana, and Peru.
Crenicichla.—Body low, sub-cylindrical; scales small or rather small. The spinous portion of the dorsal is much more developed than the soft, both being continuous, and not separated by a notch; anal spines three. Præopercular margin serrated. Each jaw with a band of conical teeth. The outer branchial arch with short tubercles. Dorsal and anal fins naked.
Ten species from Brazil and Guyana.