Dictionary of Ichthyology  

hypohyal = the one or two deep, endochondral bones in the hyoid arch between the ceratohyal and the glossohyal. Articulates dorsally with the ceratohyal and ventrally with the basihyal. Lepisosteus has only one while Gadus has two, the dorsal hypohyal or dorsohyal and the ventral hypohyal or ventrohyal. .
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.

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