A new basidiomycete family Mycogelidiaceae with a new genus Mycogelidium is established to accommodate a Gelidium-like or coralloid macrofungus producing pycnidioid, long-beaked, basidium-bearing bodies, with transversely septate basidia and ellipsoid basidiospores. The gross morphology and anatomic structure of a new species are described and illustrated in a detail, and its distinctions from fungi with similar basidium-bearing structures are discussed. Basidiopycnidium is coined to term the well-developed, pycnidioid, basidium-bearing structure.