This species has been referred to the genera Poecilobrycon and Nannobrycon in the past and in the aquarium hobby is also known as ‘oneline’ or ‘red fin’ pencilfish. It’s a popular aquarium fish and has an interesting oblique swimming-style, a behavioural trait shared only with N. eques among congeners.

The most recent diagnosis of the species appears to be that giv…

This species is traded under various other names including ‘red arc pencilfish’, ‘Peruvian red pencilfish’, ‘ruby red pencilfish’, ‘red pencilfish’, and Nannostomus cf. marginatus ‘red’.

It was initially described as a subspecies of N. marginatus but can be identified by the following combination of characters: pronounced sexual dimorphism with adult males exhibiting bright red pigmentation between the central…

This species is also known as the ‘spraying’, ‘splashing’ or ‘jumping’ tetra and these names are also sometimes applied to its congeners although none of them exhibit a comparable spawning strategy, simply depositing their eggs among vegetation at or around the water surface.

Several Brachyrhamdia species have developed colour patterns that mimic syntopically-occurring Corydoras spp. throughout the life-cycle, and the remainder may mimic Otocinclus or smaller Corydoras spp. when juvenile.

Among other catfishes they’re closely-related to members of the genus Pimelodella, but differ in…

Hemiodus species can be a very skittish when first introduced to the aquarium, but usually settle down over time, especially if a large number are being kept together. All of them look superficially similar, but can be distinguished by differences in patterning. None are particularly common in the hobby….

Hemiodus species can be a very skittish when first introduced to the aquarium, but usually settle down over time, especially if a large number are being kept together. All of them look superficially similar, but can be distinguished by differences in patterning. None are particularly common in the hobby. H. ternetzi can be identified by the fact that the black lateral stripe extends to behind the eye, and thehas no pigmentation….

Hemiodus species can be very nervous when first introduced to the aquarium, but usually settle down over time, especially if a large number are being kept together. All of them look superficially similar, but can be distinguished by differences in patterning. None are particularly common in the hobby….

Hemiodus species can be a very skittish when first introduced to the aquarium, but usually settle down over time, especially if a large number are being kept together. All of them look superficially similar, but can be distinguished by differences in patterning. None are particularly common in the hobby….

Hemiodus species can be a very skittish when first introduced to the aquarium, but usually settle down over time, especially if a large number are being kept together. All of them look superficially similar, but can be distinguished by differences in patterning. None are particularly common in the hobby….

Hemiodus species can be very nervous when first introduced to the aquarium but usually settle down over time, especially if a large number are being kept together. All of them look superficially similar, but can be distinguished by differences in patterning. None are particularly common in the hobby, but H. gracilis is probably the most often seen. It is sometimes sold as the red or red-tailed hemiodus and was previously considered a member of the now defunct genus Hemiodopsis….