Hyoid Arch

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Related to second pharyngeal arch: hyoid arch, First pharyngeal arch

hyoid arch

[′hī‚ȯid ‚ärch]
Either of the second pair of pharyngeal segments or gill arches in vertebrate embryos.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Hyoid Arch


part of the visceral skeleton in vertebrates, including man, located directly behind the maxillary arch. In most cartilaginous fishes, each half of the hyoid arch consists of a superior hyoid cartilage and an inferior hyoid cartilage. Both halves of the hyoid arch unite below in an unpaired element. In bony fishes the superior element of the hyoid arch, which bears the gill cover, is segmented into the suspensorium proper and a connective bone; the hyoid bears rays of the branchiostegal membrane. The unpaired connective element of the hyoid arch is covered with a mucous membrane (the tongue of fishes) and is often equipped with teeth. In most terrestrial vertebrates, including man, the suspensorium is converted into an auditory ossicle known as the stapes, whereas the inferior element becomes part of the hyoid apparatus.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.