S. pappaterra is relatively rare in the ornamental trade and much sought after by enthusiasts.

It is easily distinguished from all known congeners by presence of a series of prominent black blotches beneath the dorsal-fin, plus a well-defined dark band extending along the side of the body. In recent genetic analyses its genetic distinctness was strongly supported, with S. jurupari and S. leucosticta its closest relatives.

Widely-distributed throughout the Amazon, Orinoco, Essequibo, and Tocantins river systems in Brazil, Peru, Bolivia, Ecuador, Colombia, Venezuela, and Guyana.

Type locality is ‘Rio Cupai [= Rio Cupari], Rio Tapajós basin, Amazon River drainage, Pará State, Brazil’.

This species was described from Suriname but no specific locality was given.

It’s currently accepted to occur throughout much of the Amazon river system in Brazil, Peru and Bolivia with additional records from coastal drainages of Guyana, Suriname and French Guiana plus the island of Trinidad (Trinidad and Tobago).

This species is very rare in the aquarium hobby and may never have been available on a commercial basis although it has been collected, bred and distributed by some private collectors.

It’s a member of the putative G. surinamensis ‘group’ of closely-related species within the genus and ca…

In the upper Iténez it most commonly inhabits riparian zones with sandy substrates or edges of sand banks, although it’s also been collected in smaller streams and residual flood waters.

It typically forms large aggregations of up to several thousand individuals and at the confluence of the ríos Paraguá and Iténez occurs sympatrically with the congener C. paragua.

T. stellatus is superficially similar to its only congener T. securis, but can immediately be identified by the presence (vs. absence) of a prominent dark spot in the dorsal-fin. It is sometimes traded as ‘platinum hatchetfish’.

The genus Thoracocharax was originally erected by Fowler in 1906 as a subgenus of Gasteropelecus, but was elevated to generic status by Weitzman (1960).

C. strigata is an enduringly popular species in the aquarium hobby but is not bred on a commercial basis with all fish offered for sale collected in the wild.

It can be told apart from other members of the genus by its larger adult size and dark, marbled colour pattern appearing as a series of dark and light stripes running diagonally across the body below the lateral line.

This colour pattern is variable and popul…

This species may be referred to using a variety of names including ‘scomb’, ‘sabre tooth tetra’, ‘sabre tusk barracuda’, ‘dog tooth characin, ‘vampire fish’, ‘Cachorra’ or Pirandirá (the latter two names being used in Brazil where they’re also applied to congeners).

It’s regularly confused with the payara, H. armatus, though that species grows considerably larger, is pop…

C. guapore is a sought after aquarium fish although it is not often traded. It exhibits slightly different behaviour to the majority of congeners in that it tends to form aggregations in midwater and spends a large proportion of its time away from the substrate. Its morphology exhibits corresponding adaptations towards a pelagic existence with a relatively large eye, a more terminal mouth position, more strongly-forked caudal-fin, and more symmetrical body shape than most other Corydoras species.

C. caudimaculatus may be confused with the congener C. similis but can be told apart by possession of a well-defined, blackish spot on the caudal peduncle vs. a ‘smudged’ bluish marking.

C. guapore also has a comparable colour pattern but possesses a distinctly rounded snout and tends to swim above the substrate.