Figure 3. A in Redescription of 'Amyzon' brevipinne and remarks on North American Eocene catostomids (Cypriniformes: Catostomidae)

Figure 3. A juvenile or young adult and skulls of Wilsonium brevipinne from the Eocene Allenby Formation, Blakeburn Mine, British Columbia, Canada. A, juvenile or young adult, UALVP 12159; B, skull of UALVP 12658; C, line drawing of composite skull based on UALVP 12159 and UALVP 12658. Arrows indicate the frontal bones. Abbreviations: aa, anguloarticular; c1–4, the space for centra 1 through 4; d, dentary; e, ethmoid; fr, frontal; hm, hyomandibular; iob, infraorbitals, iob 1 (lacrimal) through iob 5 numbered from anterior to posterior; iop, interopercle; ke, kinethmoid; le, lateral ethmoid; m, maxilla; nc, neural complex; ns4, neural spine of the 4th vertebra; op, opercular; p, palatine; pa, parietal; pm, premaxilla; pop, preopercle; pt, pterotic; q, quadrate; r4, the 4th rib or rib of the 4th vertebra (also known as outer arm of os suspensorium in some taxa); ra, retroarticular; so, supraorbital; soc, supraoccipital; sop, sub-opercle; sp, sphenoid. Scale bars: A = 10 mm; B = 5 mm.