Other characiforms

This species is not normally aggressive towards conspecifics with juveniles in particular exhibiting a marked schooling instinct. Older individuals tend to be more solitary but still group together from time-to-time, and it's best maintained in numbers of four or more. One important point to note is that acestrorhynchids are can...

The vernacular name of this fish is derived from its appearance and behaviour, rather than a genetic association with the marine barracuda, and it's also sometimes referred to as 'pike characin' or 'spotted cachorro' with local vernacular names including 'Grand dent-chien' (French Guiana), ' Cachorrinho' or 'Ueua' (Brazil). Although most species of Acestrorhynchus appear superficially similar to one another most exhibit distinguishable external chara...

This species is a member of the putative A. nasutus group of closely-related species within the genus alongside A. nasutus, A. maculipinna and A. isalineae. These are characterised by possession of two dark, longitudinal stripes, one running from the tip of the snout to the base and the other from the posterior edge of the lower maxilla to the underside of the caudal peduncle.

This species is a member of the putative A. nasutus group of closely-related species within the genus alongside A. nasutus, A. maculipinna and A. isalineae. These are all characterised by possession of two dark, longitudinal stripes, one running from the tip of the snout to the base and the other from the posterior edge of the lower maxilla to the underside of the caudal peduncle.

An obligate piscivore capable of consuming quite large prey in relation to its body size although it tends to focus on smaller prey such as tetras and related species. Newly-imported specimens may refuse to accept anything but live fishes although most can be weaned onto dead alternatives once they recognise them as edible, and some even learn to accept dried foods.

An obligate piscivore capable of consuming surprisingly surprisingly large prey. Newly-imported specimens may refuse to accept anything but live fishes although most can be weaned onto dead alternatives once they recognise them as edible, and some even learn to accept dried foods- Like the vast majority of predatory fishes this specie...

Boulengerella differs from Ctenolucia, the only other genus currently contained in the family Ctenolucidae, by a series of derived features including possession of 87-124 (vs. 45-50) lateral line scales, presence of a strongly (vs. weakly) developed fleshy appendage at the tip of the snout and absence (vs. presence) of fleshy flaps on the lower jaw. Within the order Characiformes the family Ctenoluciidae is also distinguished by a set o...

Both species also possesses a broader dark midlateral stripe on the body which tends to be more well-defined in B. lateristriga than in B. maculata. Colour pattern in B. maculata varies considerably with some specimens noticeably paler than others, for example, and the the broad midlateral stripe usually less intense in such individuals. This does not app...

This species is currently the only described member of its genus although colour pattern and morphology vary considerably across its range. You may see reference to this species being the only fish species to possess infra-red vision, but other species also possess this ability and we suspect that infra-red plays an important role in the reproductive cycle of many fishes.

C. hujeta is traded under various names including 'slant-nosed gar', 'hujeta gar', 'rocket gar' and 'freshwater barracuda' but it and other members of the family Ctenoluciidae have traditionally been referred to as 'pike characids'. They're all predatory fishes native to South America, included in the order Characiformes and currently spread across two genera; Ctenolucius with two species and Boulengerella with five. The two genera are ...

This species is rare in the aquarium trade but is arguably more suitable for the home aquarium than some of its better-known relatives given its adult size and relatively docile behaviour. Other vernacular names include 'Dientón' (Peru), 'Perrito' (Ecuador), 'Payara-chata' or 'Payarin' (Venezuela) and 'Icanga', 'Minguilista' or 'Peice-cachorro' (Brazil), some of which are also applied to related species.

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...

Quite widely distributed having been recorded from Brazil, Colombia, Peru and Venezuela. It's been collected from the upper parts of several major river drainages including the Río Negro, Río Orinoco (including the Río Inírida and Casiquiare canal) and Río Solimões. The type series was collected from 'Igarapé Préto', Brazil, said to be 60 kilometres to the south of the Colombian border city Leticia. Populations from Colombia and Brazil tend to be more intensely-coloured, and the Peruvian populations may apparently represent an undescribed species.

It's known by various vernacular names including 'Pirá-pacu', 'Pira-pucu' or 'Diente de cao' (central Amazon), 'Bicuda' or 'Uena' (rio Tocantins), 'Bicuda' (rio Tapajós), 'Aguejeta' or 'Picua' (Venezuela), and 'Moruwi' or 'Pirapoko' (Guyana). The entire dorsal-fin base is located anteriorly to a vertical through the anal-fin origin and this character distinguishes it from all other ctenolucids except B. lucius and B. xyrekes.

This species is largely unsuitable for the home aquarium given its eventual size and natural behaviour, and we know of only a handful of private aquarists with the facilities required to house it long-term. Nonetheless juveniles and subadults are sometimes available in the trade although often misidentified as the congener B. maculata.

H. armatus should probably not be considered a home aquarium subject at all given its eventual size and migratory natural behaviour. Unfortunately, juveniles are seen for sale quite regularly, most often without adequate information regarding their long-term care, and it's common to see them being maintained in medium-sized aquaria with no possibility of achieving their potential.

Vernacular names in Brazil include 'Cachorra' or 'Pirandirá', although these are also applied to congeners. It can be told apart from all congeners by the following combination of characters: head and body silvery with dark dorsal surface; an elongate dark blotch posterior to the opercle; dorsal, caudal and anal-fin rays reddish to orange proximally with some individual variation in intensity and tonality; adipose fin dark, with diffuse black pigmentation.

R. vulpinus is the most widely-distributed member of the family Cynodontidae. Type locality is given simply as 'Brazilian rivers', but this species is currently understood to be distributed in the Amazon basin from the Río Ucayali system in Peru, eastward as far as the rio Xingu in Brazil, plus the rio Tocantins and Rio Capim basins. It's also known from the Río Orinoco ba...