Pharyngeal arch primordia and CNC condensation patterns that form craniofacial cartilages in zebrafish. Lateral views at 28 hours (A,B) and 72 hours (C,D) postfertilization. A) Schematic illustrating dorsal (D1,D2) and ventral (V1,V2) groups of skeletal precursors. Green circles, ventral branchial arches. Purple oval (arrow), precursors of the neurocranium. Asterisks indicate the mandibular joint. B) Schematic illustrating the cylindrical organization of arch primordia. Mesoderm (brown) is surrounded by CNC (red, white and blue) which form dorsal and ventral condensations. Joint precursors (white) express bapx1 in the mandibular arch. These groups of arch mesenchyme are surrounded by endodermal (yellow) and ectodermal (green) epithelia. C) Camera lucida drawing of larval cartilages of the mandibular (red), hyoid (blue) and branchial (green) arches, as well as the neurocranium (purple). D) Camera lucida drawing of flat-mounted, dissected cartilages of the mandibular and hyoid. Abbreviations: ch, ceratohyal; hs, hyosymplectic; ih, interhyal; mc, meckel's cartilage; pq, palatoquadrate; tr, trabeculae.