Appendidspora: a new genus in the arbuscular mycorrhiza-forming Glomeromycetes, with a discussion of the genus Archaeospora

摘要

A new genus of arbuscular mycorrhizal fungi, Appendidspora (Archaeosporaceae), is described. New species names are: (i) Ap. appendicula, the type species derived from the dimorphic Acaulospora appendicula, a "synonym" of Ac. gerdemannii erroneously thought to represent the acaulosporoid form of Archaeospora leptoticha; (ii) Ap. gerdemannii, based on Archaeospora (Glomus) gerdemannii; and (iii) Ap. jimgerdemannii, a nom. nov. for the former Ac. gerdemannii. Archaeospora trappei, which remains alone inthe now monotypic Archaeospora, differs from the Appendidspora species in spore development, wall morphology, germination, and root colonization structures; its separation is further supported by molecular data. In Appendidspora, acaulosporoid spores are all three-walled and have an appendix arising laterally from the hyphal neck of a terminal sporiferous saccule. Distributional data are provided that expand the range of Appendidspora species from the Mediterranean and (sub)tropical climates to arbuscular mycorrhizal fungi communities in cold subalpine and alpine areas.