overlaps pharyngeal arch 4 pharyngeal arch 5 pharyngeal pouch pharyngeal pouch 4 fourth arch pharyngeal pouch EHDAA2:0000091 EFO:0003637 4th pharyngeal pouch endoderm 4th arch branchial pouch endoderm SCTID:362858001 fourth pharyngeal pouch VHOG:0000578 VHOG:0000971 FMA:295688 fourth visceral pouch AAO:0011117 pharyngeal pouches 4 XAO:0000254 NCIT:C34181 4th arch branchial pouch fourth branchial pouch Wikipedia:Pharyngeal_pouch_(embryology)#Fourth_pouch visceral pouch 4 4th branchial pouch TAO:0001134 RETIRED_EHDAA2:0000090 ZFA:0001134 EMAPA:16766 A pharyngeal pouch between pharyngeal arch 4 and arch 5 or 6 (a fifth arch never establishes in amniotes).