Extended Data Fig. 6: Reinterpretation of ectotympanic of Qishou and Arboroharamiya.

a–c, Qishou jintzang, the so-called left ectotympanic in ventral (a) and dorsal (b) views, derived from figure 8c, d of ref. ¹⁷; interpreted here as the left malleus with broken anterior process and incus in dorsal view (c). d, Arboroharamiya allinhopsoni, the so-called left ectotympanic in ventral view, derived from figure 3 of ref. ¹⁷. e, f, Tachyglossus aculeatus (Carnegie Museum 50812), isolated left ectopterygoid bone and the left basicranium in ventral view. g, Arboroharamiya jenkinsi, the so-called left ectotytmpanic in ventral view, derived from figure 7c of ref. ¹⁷. h, i, Ornithorhynchus anatinus (Carnegie Museum 50815), isolated left ectopterygoid bone and the left basicranium in ventral view. Colours for the auditory elements are as in Fig. 1. api, anterior prominence of incus; apm(br), anterior process of malleus (broken); arty, anterior edge of ectotympanic; cb, crus breve; cfm, contact area for malleus; ep, ectopterygoid; frt, fracture; mm, manubrium of malleus; prty, posterior edge of ectotympanic; rtm, ridge for attachment of anterior part of tympanic membrane; sp, stapedial process of incus; ty-d, lateral ectotympanic part presumably equivalent to dorsal part of angular; ty-r, ectotympanic part presumably equivalent to reflected lamina.