Hemiancistrus

Hemiancistrus
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Siluriformes
Family:	Loricariidae
Subfamily:	Hypostominae
Genus:	Hemiancistrus Bleeker, 1862

Hemiancistrus is a genus of suckermouth armored catfishes. These species are native to South America. The taxonomy of this genus is complex and unclear, and major work has to be done. Many of these fish are popular aquarium fish.

Hemiancistrus is a genus within the tribe Ancistrini of the subfamily Hypostominae. This genus has long been used as a sort of dump for Loricariid species; fish with unclear relationships have been classified to this genus. As such, this taxon is not monophyletic. At this point, many undescribed species remain.

This genus and the closely related Peckoltia may be synonymous, as neither genus is supported by synapomorphies. Hemiancistrus species differ from other members of the Panaque clade lacking the synapomorphies of the other genera and having the dentaries meeting at an angle greater than 120°; in Peckoltia species, the dentaries meet at less than 90° Generally, Peckoltia are considered to be those that have dorsal saddles and bands in the fins, while Heminancistrus have spots and uniform coloration.

What species belong to this genus has been unclear. Many newer species have been tentatively assigned to Hemiancistrus. Although the recently described H. micrommatos and H. spinosissimus have been considered synonyms of H. spilomma by Armbruster, they have more recently been considered valid.H. micrommatos, H. spinosissimus and H. spilomma are placed in the genus Ancistomus.Hemiancistrus medians is larger than most species that were left in Hemiancistrus, has well-developed keels (only present elsewhere in ‘H.’ landoni), and a different body shape. The remainder of the taxa that do not have established genera that they can be placed in will be recognized as species groups in ‘Hemiancistrus’ in single quotes until they can be examined further.

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