Studies on the taxonomy of the Myxobacterales II. Polyangium and the demise of the Sorangiaceae 1

The order Polyangiaceae is redefined to include only those myxobacters with cylindrical cells, It includes all organisms formerly included in the Sorangiaceae and the genera Chondromyces and Synangium. A new family, the Cystobacteraceae, type species Cystobacter fuscus (Polyangium fuscum), is erected for sporangial myxobacters with tapered vegetative cells. It includes the genera Stigmatella and Podangium in addition to Cystobacter.