Dictionary of Ichthyology  

hyomandibula = the upper paired deep bone or cartilage of the hyoid region, sometimes taking part in jaw suspension and which supports the opercle. Dorsally it articulates with the otic capsule at the hyomandibular fossa, ventrally with the quadrate and symplectic. In most Teleostei it has a foramen for the hyomandibular branch of the facial nerve (VII). Often spelled hyomandibular.
Visceral arch of Scyllium (= Scyliorhinus), BH = basihyal, C = copula (united basibranchials), E = epihyal, H = hypohyal, HM = hyomandibula, HY = hyoid, K = keratobranchial, P = pharyngobranchial, from Kingsley's "Textbook of Vertebrate Zoology, 1906. Photograph by Brian W. Coad.....more

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