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Neopterygian node M: Presence of three hypobranchials and of four pharyngobranchials.
The osteoglossomorphs are a relatively 'little' extant group of teleosts, containing 'only' about 200 species that probably appeared in the Late Jurassic. These live mostly in southern hemisphere freshwaters. The Osteoglossum - above left - is a South American form, while Mormyrus - above right - is an African osteoglossomorph more commonly known as the "elephant fish", possessing caudal electric organs. This clade is characteristic in having shifted the main bite away from the maxilla and lower jaw, using a bony tooth bearing component of their tongue and a basibranchial element against teeth on the parasphenoid of their palate instead. This earned them their name, literally "bony-tongue-form", in Greek.