Myxomycete biodiversity of the Colorado Plateau

A rapid biodiversity assessment for myxomycetes (plasmodial slime moulds) was carried out during a two-week field trip to the Colorado Plateau (western U.S.A.). Due to the very arid climate of the region, the moist chamber culture technique formed a major part of the survey. A total of 1165 records belonging to 93 species and 1 variety from 27 genera was collected from the 433 moist chamber cultures prepared with the bark surface of living plants, litter and weathered dung of herbivorous animals. Only 31 specimens of 16 wood-inhabiting species were collected in the field, mainly at higher elevations. Subsequent moist chamber cultures produced numerous bark-inhabiting species that are usually considered to be rare, including Echinostelium coelocephalum, Protophysarum phloiogenum, and Macbrideola declinata. The most common litter-inhabiting species were Didymium mexicanum and Badhamia melanospora (mainly on decaying parts of Opuntia spp. and Agave spp.); the most abundant coprophilous species were Badhamia cf. apiculospora, Fuligo cinerea, Perichaena liceoides, and Licea tenera. Both, species richness and diversity, increase from sagebrush desert to pine-juniper open woodland and pine-oak woodland. The myxomycete biota of the Colorado Plateau displays a high level of similarity to those of other arid regions of the world (mean coefficient of community Cs = 0.67), differing considerably from temperate (mean Cs = 0.34), boreal (mean Cs = 0.49) and tropical biotas (mean Cs = 0.42).