Extended Data Figure 4: H. reesei from the Spence Shale (specimen KUMIP204340).

a, b, Operculum, showing extended pharynx and lophophore. a, Specimen photographed dry with polarized light. b, Specimen photographed wet with polarized light. c–e, Whole specimen photographed dry with unpolarized light (c), dry with polarized light (d) and wet with polarized light (e). Scale bars, 2 mm (a, b) and 5 mm (c–e). Abbreviations: c, conical shell; ct, connective tissue; g, gut; lh, left helen; m, mouth; o, operculum; p, pharynx; pl, pharynx lumen; rh, right helen; t, tentacle.