In all vertebrates, the pharyngeal apparatus develops from a series of bulges found on the lateral surface of the head, the pharyngeal arches, which consist of a number of different embryonic cell types. Each arch has an external covering of ectoderm and inner covering of endoderm, and between these a mesenchymal filling of neural crest with a central core of mesoderm.[well established][VHOG]

2nd branchial arch mesenchyme, pharyngeal arch 2 mesenchyme

uberon

UBERON:0005689

2nd arch mesenchyme

• stapes pre-cartilage condensation
• lenticular process of incus bone

• mesenchyme of middle ear

• 2nd arch mesenchyme from head mesenchyme
• 2nd arch mesenchyme from neural crest