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


Swedish Museum of Natural History, NRM

Acaronia vultuosa Kullander


Acaronia vultuosa Kullander, 1989. Zool Scr. 18, p. 447 (Venezuela, Terr. Federal Amazonas, Departamento Ature, small drying backwater pool off road from El Burro to Puerto Ayacucho, approximately 05°47'N, 67°29'W).


Distinguished from Acaronia nassa by (1) the absence of microbranchiospines on the first gill arch; (2) the separate anterior external gill rakers on first gill arch which are not 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 horizontally elongate, forming a short horizontal band instead of being irregularly rounded as it is in A. nassa. Blackish spots marking the openings of the distal extrascapular lateralis canal are not present in A. nassa. A dark stripe runs posteroventrad from the posttemporal lateralis canal opening and is extended to the scale below the first trunk lateral line scale; in A. nassa there is a spot on the posttemporal and another on the first lateral line scale. Dark horizontal lines on sides are formed by dark pigment on the middle third of scales instead of marginal parts of scales. The squarish midlateral spot is large and extends from the lateral band dorsally to or almost to the lateral line canal row, instead of elongate and not rising much above the lateral band. The caudal fin is mostly immaculate posterior to the muscular base, instead of densely spotted. (From Kullander, 1989.)

The largest specimen examined is about 131.5 mm SL.


MBUCV-V 17714. Adult female, 87.0 mm SL. Venezuela, Territorio Federal Amazonas, Departamento Ature, small drying backwater pool off road from El Burro to Puerto Ayacucho, approximately 05°47'N 67°29'W. 11 December 1984. Richard P. Vari, O. Castillo & C. Ferraris (Field no. RPV 84-27).


The Latin adjective vultuosus means full of facial expressions or grimaces. It was given with reference to the species diagnostic conspicuous black markings on the head.

Geographical distribution

Río Orinoco basin, including the lower Caura, Vichada and Inírida drainages, the Río Casiquiare and the upper Río Negro basin, in Venezuela, Colombia and Brazil. The geographic range overlaps slightly with that of the widespread Amazonian species A. nassa. The species were found associated on the Ilha Tamaquaré. Acaronia nassa ascends the Rio Negro some distance further upstream, to the mouth of the Rio Marauiá.
Lifemapper map

Natural history

No information available.

Local names

Not recorded.


KULLANDER, S.O. 1989. Description of a new Acaronia species from the Rio Orinoco and Rio Negro drainages. Zool. Scr. 18: 447-452.