Fig. 8

Summary of Gsx expression (blue) during the development of the scaphopod Antalis entalis and the cephalopod Idiosepius notoides. Dorsal (d)–ventral (v), anterior (a)–posterior (p), and left (l)–right (r) axes indicate the orientation and are the same in each of the six columns. Shown Gsx-expressing cell somata do not represent absolute numbers. a–f Sketch drawing depicting a mid-stage trochophore (a, b), a late-stage trochophore (c, d), and a postmetamorphic (settled) individual (e, f) of Antalis entalis. Gsx-expressing cell somata are labeled with red numbers 1–4 (c.f. Figures 6, 7). g–l Sketch drawing depicting developmental of stage 19 (g, h), stage 25 (i, j), and stage 28 (k, l, yolk sac removed) of the pygmy squid Idiosepius notoides. ab anterior basal lobe, ao apical organ, ar arm, bc buccal cone, cg cerebral ganglion, cp captacula, ey eye, f foot, fn funnel, ib inferior buccal lobe, if inferior frontal lobe, m mantle, mf mantle fold, mo mouth, o optic ganglion/lobe, pb posterior basal lobe, pg pedal ganglion, pt prototroch, pv pavilion, pvg palliovisceral ganglion, ps posterior subesophageal mass and y yolk. Scale bars a–f 50 µm, g–l 150 µm