Acaronia is distinguished by its large gape, correlating with long ascending premaxillary processes reaching beyond middle of orbit. There are only two species known in this genus.





Sven O Kullander


Acaronia nassa (Heckel)


Acara nassa Heckel, 1840. Annln wien. Mus. Natges. 2, p. 353 (Rio-Guaporé).
Acara cognatus Heckel, 1840. Annln wien. Mus. Natges. 2, p. 356 (Barra do Rio-negro).
Acara unicolor Heckel, 1840. Annln wien. Mus. Natges. 2, p. 357, Pl. XXX, fig. 25 (Barra do Rio-negro).
Centrarchus ?? rostratus Jardine, 1843. Nat. Libr. Ichthyol. 5, p. 163, Pl. 15 (Rio Negro).
Apistogramma ambloplitoides Fowler, 1940. Proc. Acad. nat. Sci. Philad. 91, p. 281, Fig. 63 (Ucayali River basin, Contamana, Peru).

Acaronia nassa, NRM 28298, adult, freshly preserved, from Brazil, Amapá, Juminán, near Cunene village. 28 March 1994 (SOK 94-035). Photo © S.O. Kullander.
Acaronia nassa, NRM 28298, adult, freshly preserved, from Brazil, Amapá, Juminán, near Cunene village.
28 March 1994 (SOK 94-035). Photo: S.O. Kullander.


Distinguished from Acaronia vultuosa by (1) having microbranchiospines externally on all gill arches and internally on the fourth gill arch; (2) anterior external gill rakers on first gill arch coalesced into long tooth plates; and (3) the colour pattern. In A. vultuosa the suborbital stripe usually is not interrupted as it is in A. nassa, and when divided the dorsal and ventral portions are not widely separated. The supraorbital spot is rounded instead of horizontally elongate, forming a short horizontal band instead of being irregularly rounded as it is in A. vultuosa. There are no blackish spots marking the openings of the distal extrascapular lateralis canal. A dark spot on the posttemporal and another on the first lateral line scale, but no stripe running posteroventrad from the posttemporal lateralis canal opening. Dark horizontal lines on sides are formed by dark pigment on the marginal parts of the scale instead of the middle third of scales. The midlateral spot is elongate and not rising much above the lateral band instead of rectangular and large, extending from the lateral band dorsally to or almost to the lateral line canal row. The caudal fin is richly spotted instead of mostly immaculate posterior to the muscular base.

Primary types

Acara nassa. — Syntypes: NMW 10538-10540. 3, 125.5-154.4 mm SL. 'Rio Guapore, Brasilien'. No date. J. Natterer; NMW 16185. 1, 138 mm (stuffed). 'Mato Grosso'. 12 Jan 1829. J. Natterer; NMW uncat. 1, ca 136 mm (stuffed). No locality. No date. J. Natterer.
Acara cognatus. — Holotype, NMW 33619. 127.0 mm SL. 'Brasilien, Rio-negro' [Manaus]. No date. J. Natterer.
Acara unicolor. — Syntypes, NMW 33347. 2, ca 109.1-139.5 mm SL. 'Brasilien, Rio-negro' [Manaus]. No date. J. Natterer.
Centrarchus ?? rostratus. — Lost.
Apistogramma ambloplitoides. — Holotype, ANSP 68681. 77.5 mm SL. Peru, Departamento Loreto, Contamana. Jul-Aug 1937. W.C. Morrow.


ambloplitoides refers to similarity with Ambloplites, a genus of the Centrarchidae, with the Greek suffix -oides, from eidos, Greek noun meaning look, appearance, etc.
cognatus, -a, -um is a Latin adjective, meaning related by birth, or similar.
nassa is a Latin noun meaning fyke-net, wire cage or similar fish basket, a translation of Tupi-Guarani juquiá, referring to a meaning fish basket trap with wide opening.
rostratus, -a, -um is a Latin adjective, from the noun rostrum, snout, bird beak, elephant trunk, etc.; to emphasize the length of the snout.
unicolor, -oris is a Latin adjective meaning of a single colour, from unus, one and color, colour.

Geographical distribution

Peru, Brazil, French Guiana, Guiana, Bolivia, including drainages Amazon (including Bolivian Amazonia, Rio Negro), Tocantins, Essequibo, Oyapock. Ascends the Rio Negro to the mouth of the Rio Marauiá, overlapping with A. vultuosa descending to the Ilha Tamaquaré.
Lifemapper map

Natural history

In Peru, Acaronia nassa was collected mainly from the Río Nanay drainage, chiefly in drying floodplain lakes, but the species was found also in a stream and on a sand playa (Kullander, 1986).

Local name

'Cara, bocca de Juquià' (=Acará boca do juquiá), in Vila Bela, according to Natterer (in Heckel, 1840).


FOWLER, H.W. 1940. A collection of fishes obtained by Mr. William C. Morrow in the Ucayali River Basin, Peru. Proc. Acad. nat. Sci. Philad. 91: 219-289.
HECKEL, J. 1840. Johann Natterer's neue Flussfische Brasilien's nach den Beobachtungen und Mittheilungen des Entdeckers beschrieben. (Erste Abtheilung, die Labroiden.) Annln wien. Mus. Natges. 2: 327-470.
JARDINE, W. (ed.). 1843. The naturalist's library [vol. 38]. Ichthyology Vol. V. Fishes of Guiana. Part II Edinburgh, 214 pp. [Also as Vol. XXXI. Ichthyology. Fishes of British Guiana. Part 2nd. Two pl. 18 listed in text and Contents, but only one present.]
KULLANDER, S.O. 1986. Cichlid fishes of the Amazon River drainage of Peru. Swedish Museum of Natural History, Stockholm, 431 pp.
KULLANDER, S.O. 1989. Description of a new Acaronia species from the Rio Orinoco and Rio Negro drainages. Zool. Scr. 18: 447-452.