pharyngeal arch pharyngeal arch 4 4 visceral arch 4 UBERON:0003115 4th visceral arch branchial arch 2 VHOG:0000299 XAO:0000449 EHDAA:1663 fourth pharyngeal arch The second pharyngeal/branchial arch; arises as a thickening of the pharygeal wall between the first and second branchial clefts; contains the second aortic arch; forms part of the hyoid bone, tongue and facial musculature.[AAO] Contributes to development of the cartilage of the larynx, laryngeal, pharyngeal, and soft palate muscles, superior parathyroid gland, and C-cells of the thymus. in XAO, called branchial arch 2 and df VP4 FMA:293035 TAO:0001599 SCTID:308770007 4th arch ZFA:0001607 second gill arch EMAPA:16760 gill arch 2 EHDAA2:0000086 fourth visceral arch AAO:0010366 4th pharyngeal arch second branchial arch A conserved feature of all vertebrate embryos is the presence of a series of bulges on the lateral surface of the head, the pharyngeal arches; it is within these structures that the nerves, muscles and skeletal components of the pharyngeal apparatus are laid down. The pharyngeal arches are separated by endodermal outpocketings, the pharyngeal pouches.[well established][VHOG] 4th branchial arch