Danionella

This species is available in the trade on occasion and has been sold as Danionella sp. 'neon green' or 'flourescent green'. The specific name was inspired by its jaw morphology which according to current knowledge is unique among cypriniform fishes. Both upper and lower jaws contain a series of toothlike odontoid processes; these are only rudimentary in females but in males appear to form rows of teeth of which the front pair is large and fang-like. The upper fangs project th...

As far as we know this species has not been bred in aquaria although Pete Liptrot and Paul Dixon of the Bolton Museum Aquarium, UK, have achieved great success with an unidentified congener. They first noticed fry from their group of 24 adults after moving the school to a dedicated set-up planted with mature Java moss and have since rewarded with regular batches of fry.

The anatomical structure of miniaturised cyprinids can vary greatly; there are two putative groups with some species possessing intermediate features to some degree. The first contains those fishes which though small are essentially proportionally dwarfed versions of their larger relatives. The other includes those in which anatomical development stops at a point where adult still resemble a larval form of their larger ancestor, as in...