Extended Data Fig. 3: Coronal sections through anterior of Youti yuanshi.

a–o, Virtual dissections of YKLP 12387 rendered from XCT data, from dorsal to ventral. Coloured regions identify organ systems. Raw images available at FigShare84. Abbreviations: a, appendage; an, anterior compartment of first appendage; cb, central body of brain; cc, circumpharyngeal connective; co, circumoral ring; db, dorsolateral body of brain; dg, digestive gland; dp, dorsal projection; dv, dorsal vessel; e, eye; fb, frontal body of brain; irr, irregular chamber; lac, lacuna; mm, transverse medial membrane of the central body; po, posterior compartment of first appendage; pph, peripheral cavity; sep, membrane separating compartments of the first appendage; sp, subpharyngeal gland; tm, transverse membrane; vl, ventrolateral sinus.