Figure S1. Lithocolla globosa

Figure S1. Lithocolla globosa SnP. A-B) Agglutinated cells from enrichment with sediment stillpresent. Surface view (B) showing attached mineral particles. C-O) Cells from culture, fed onNavicula (C-G), Isochrysis (H,L-O) and Phaeodactylum (I-K). C-D) General view of same cell.Note nucleus (in C) and ingested diatoms (in D), orange globules (D inset, bracket) and layer(D inset, arrowhead). E) General view of cell. Note nucleus, orange globules and greenishdigestive vacuoles. F-H) Examples of intact filopodia. Note that filopodia degrade rapidly underexposure to bright light. I-J) Individuals with 2 (I) and 3 (J) nuclei, relatively commonly observedin culture. K) 'Re-agglutinated' cell one day following addition of chalk dust (as fine calciumcarbonate mineral inclusions) to culture. Note mineral particles inside and on the surface of thecell, resembling the agglutinated cells from enrichment in (A-B). L-O) Pseudoseries of differentindividuals showing mineral inclusions found in cells (arrowheads), 20min (L), 23min (M), 47min(N), 60min (O) following addition of chalk dust to mineral-particle-deprived culture, indicating thatmineral particles are ingested by the cell. Differential interference contrast, scalebars are 20μm(A-K, all images at same scale), 10μm (L-O).