Megalancistrus sp.

Megalancistrus: from the Greek μέγας (mégas), meaning 'big, large, great', and the generic name Ancistrus.

Known only from the rio São Francisco system in eastern Brazil.

Suitable only for public installations or the very largest private aquaria.

Wild specimens are likely to feed primarily on aquatic invertebrates alongside smaller quantities of wood as in the congener M. paranus, although it's unclear whether the latter is an essential part of the diet or ingested unintentionally while the fish are foraging.

In the aquarium it does best when offered a varied diet comprising sinking dried foods, frozen Daphnia, mosquito larvae, chironomid larvae (bloodworm), and prawn/shrimp, for, example, plus fresh fruit, parboiled potato, etc.

Home-made foods using a mixture of natural ingredients bound with gelatin are very useful since they can be tailored to contain fresh vegetables, Spirulina and meatier ingredients.

Can behave very aggressively in confined surroundings and should only be maintained alongside similarly-sized, robust fishes in suitably-sized aquaria (see 'Aquarium Size').

L234 was previously applied to M. paranus, which has also has the L-number L113 assigned to it.

However M. paranus is native to the Paraná, Paraguay and Uruguay drainages, whereas L234 is collected in the rio São Francisco so appears to represent an unidentified species.

M. barrae and M. sp. 'LDA097' are also exported from the São Francisco system.