Supplementary Fig. S1. Migrating pseudoplasmodia of Byssovorax cruenta By c2^T deposit wrinkled, parchment-like slime tracks. Bar, 570 µm.

Supplementary Fig. S2. A knob of piled up vegetative cells of the myxobacterium Byssovorax cruenta By c2^T, resembling a Myxococcus fruiting body. On the surface of a water agar plate with a streak of autoclaved Escherichia coli. The diameter of the base of the mass is approximately 140 µm.

Supplementary Fig. S3. Instead of knobs, the pseudoplasmodia of Byssovorax cruenta By c2^T often end up in large, red rings, this one near the edge of a piece of filter paper. Bar, 100 µm.

Supplementary Fig. S4. Rarely, cup-shaped structures arise from Byssovorax cruenta By c2^T. Bar, 380 µm.

Supplementary Fig. S5. Sometimes, strains are isolated (in this case strain Pl 10973), tentatively identified as Polyangium, that also grow as pseudoplasmodia resembling those of Byssovorax. Bar, 260 µm.

Supplementary Fig. S6. Growth of Byssovorax cruenta By c2^T in the form of a coherent swarm emerging from an agar block used as the inoculum (top) and from the edge of a piece of macerated filter paper on yeast agar (bottom). Typical myxobacterial swarm colonies with long, radial veins have developed. Bars, 2150 µm.

Supplementary Fig. S7. Single sporangiole of Byssovorax cruenta By c2^T within an additional outer wall. Bar, 25 µm.

Supplementary Fig. S8. Crystals in macerated filter paper arising from cultures of Byssovorax cruenta By c2^T. Bar, 30 µm.

Supplementary Fig. S9. Intensely red oil droplets in a degenerated culture of Byssovorax cruenta By c2^T. Bar, 13 µm.

Supplementary Fig. S10. Colony of Byssovorax cruenta By c2^T on filter paper placed on mineral salts agar showing decomposition of cellulose. Bar, 1100 µm.