Hyoid bar (A–B) and gill arches (C–D) of Flexor incus, AIM MA655142, paratype, 20.0 mm SL. A Hyoid bar, right side in lateral view (image reversed) B Close up of box in A showing articulating between heads of branchiostegal rays and hyoid bar C Lower gill arches in dorsal view, paired elements of right side omitted D Upper gill arches of left side in ventral view. A single scale bar shared between C and D. Abbreviations: ACh, anterior ceratohyal; Bb3-4C, basibranchial 3 or 4 cartilages; Bh, basihyal; BrR, branchiostegal rays; Cb1-5, ceratobranchial 1-5; DHh, dorsal hypohyal; EB1-4, epibranchials 1-4; GF, gill filament; GR, gill raker; Hb1, hypobranchial 1; Hb2-3C, hypobranchial 2 or 3 cartilage; Pb3TP, pharyngobranchial 3 toothplate; Uh, urohyal.