The Distichodontidae are a family of African freshwater fishes of the order Characiformes.
Two evolutionary grades are found in this family; micropredators (predators of very small organisms like aquatic insect larvae) and herbivores have a nonprotractile upper jaw and a deep to shallow body, while carnivores have a movable upper jaw and an elongated body. Although the herbivores primarily feed on plant material, these species often have omnivorous tendencies. The carnivores include specialized fish-eaters (genus Mesoborus), fin-eaters (Belonophago, Eugnathichthys and Phago) and species that will feed on both whole fish and fins (Ichthyborus). The fin-eaters attack other fish, even ones that are much larger, where they bite off pieces of fins with their sharp teeth.Lavoué, S.; M.E.Arnegard; D.L. Rabosky; P.B. McIntyre; D. Arcila; R.P. Vari; M. Nishida (2017). Trophic evolution in African citharinoid fishes (Teleostei: Characiformes) and the origin of intraordinal pterygophagy. Molecular Phylogenetics and Evolution 113: 23-32. Matthes, H. (1961). Feeding Habit of Some Central African Freshwater Fishes. Nature 192: 78–80.Arroyave, J.; M.L.J. Stiassny (2014). DNA barcoding reveals novel insights into pterygophagy and prey selection in distichodontid fishes (Characiformes: Distichodontidae). Ecology and evolution 4(23): 4534–4542.
The fish in Distichodontidae vary greatly in size among species, with the smallest micropredators being less than in length, and the largest herbivores can reach up to .
Genera Distichodontidae contains the following genera:
Belonophago Giltay, 1929 Congocharax Matthes, 1964 Distichodus J. P. Müller & Troschel, 1844 Dundocharax Poll, 1967 Eugnathichthys Boulenger, 1898 Ichthyborus Günther, 1864 Mesoborus Pellegrin, 1900 Microstomatichthyoborus Nichols & Griscom, 1917 Monostichodus Vaillant, 1886 Nannaethiops Günther, 1872 Nannocharax Günther, 1867 Neolebias Steindachner, 1894 Paradistichodus Pellegrin, 1922 Paraphago Boulenger, 1899 Phago Günther, 1865 Xenocharax Günther, 1867
The following cladogram is based on a 2013 genetic study of Citharinoidei:
References