The genus Apistogramma is among the most speciose of South American cichlid genera with around 70 species valid at present but many more awaiting description. In addition many species exist in two or more geographical colour forms which may or may not turn out to be distinct in the future. Hobbyists tend to label these with collection data if available in order to avoid mixing them and the potential of hybridisation.

This is the type species of the genus Aequidens and has the widest distribution of any member species. It exists in various colour forms depending on locality with variants from Ecuador and Peru being particularly sought after since they develop striking red (Ecuador) or orange (Peru) colouration on the lower part of the jaw, head and anterior portion of the belly whereas those from Brazil tend to have an overall grey/blue/green colouration, for example.

Despite its type status it's long…

This species, which may also be referred to by the alternative vernacular names 'spotted raphael', 'white-spotted' or 'white-barred' catfish, is very common in the trade and despite its adult size is recommended to beginners and experienced aquarists alike since it is hardy, attractive and relatively-long-lived. The light body markings are highly variable in terms of exact placement and may be either white or pale to darkish yellow in colour.

It is very similar i…

In the igarapés Baré and Ubim, western Brazil H. erythrostigma was collected from stretches measuring 5-7 metres in width with thick riparian and overhanging vegetation.

The substrate was mostly composed of sand and the fish displayed a preference for boundary zones between shallow and deeper water. Conductivity was measured at 14.2-62.1 mS/cm³, dissolved oxy…

The broad dark stripe in the dorsal portion of the body extends into the ventral portion on the caudal peduncle, and this character can be used to distinguish it from the very similar-looking C. zygatus, with which it is often confused. In C. zygatus the dark stripe does not extend ventrally on the caudal peduncle and is present only on the dorsal part.

This species is popular in the aquarium hobby and unlike the majority of congeners tends to spend a fair amount of time away from the substrate, often forming groups in midwater.

It has been placed in the unofficial ‘C. elegans group’, which contains a number of species exhibiting similarities in morphology and colour pattern, some of which remain unidentified in scientific terms.

This species is among the more popular Corydoras in the aquarium hobby and is widely available. It may also be referred to as ‘arched cory’.

There exist a number of similar-looking congeners, particularly C. urucu (Britto et al., 2009), described from the rio Urucu in Coari municipality, Amazonas state, Brazil, and C. narcissus from the rio Purus. The latter appears to have also been traded as C. sp. ‘super arcuatus longnose’ while a larg…

The genus Apistogramma is among the most speciose of South American cichlid genera with around 70 species valid at present but many more awaiting description. In addition many species exist in two or more geographical colour forms which may or may not turn out to be distinct in the future. Hobbyists tend to label these with collection data if available in order to avoid mixing them and the potential of hybridisation.

Member species have also been organised into a series of species lineages, complexes and groups by authors in order to better separate them. Such lists have been augmented by fish that have appeared in the aquarium trade and are in a state of near-constant flux

Numerous ornamental forms of this species have been selectively line-bred for the aquarium trade, vernacular names for which include "sunset", "sunburst", "double red", "triple red", "gold", "white gold", "orange flash" and "albino". It has also been assigned the 'A' number A200 under the DATZ system with possibly conspecific, related forms similarly numbered A201, A202 and A203 depending on locality.

Th…

Given its eventual size and natural behaviour this species is largely unsuitable for the home aquarium, and we know of only a handful of private aquarists with the facilities required to house it long-term.

Unfortunately juveniles are readily available in the trade, although the scarcity of privately-maintained adults would suggest that most fail to reach their potential.