SUMMARY
Syncephalis californica is described from soils of the Sacramento Valley of California. It is distinguished from other species by the height of the sporangiophore, a 270° angle of recurvature and the uniform diameter throughout the recurved portion of the sporangiophore. Synchephalis californica induces giant hyphal swellings in its host: it parasitizes several species of Rhizopus, Mucor, Choanephora, Gilbertella, Blakeslea, Thamnostylum, Thamnidium and Zygorhynchus. Of the hosts examined, Rhizopus species are the most susceptible.