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The moist chamber culture technique was used to study the ecology of myxomycetes from a winter-cold desert of the Mangyschlak Peninsula (western Kazakhstan). A rather species-poor community of 27 myxomycete taxa, two protostelids and some undifferentiated myxobacteria was found. The rank-abundance plot is described best by a log series or a geometric model. The species that developed formed a successional sequence that correlated well with morphological features of the fructifications. Using canonical correspondence analysis, environmental parameters recorded within substrate sampling were related to species abundances. Substratum type and pH accounted for most of the variance in species distribution. Using five environmental parameters and development time as resource states, niche breadths were calculated for the 18 most common species in the study. Bark-inhabiting species were found to be more specialized than those inhabiting litter. Members of the first group tend to develop rapidly, have small, usually stalked sporocarps without a peridium and possess protoplasmodia or minute aphanoplasmodia. Members of the second group tend to have a phaneroplasmodium and develop more slowly into larger, usually sessile fructifications with often well-developed peridia. A plot of niche overlap vs Cole index of association for the most common species revealed frequent associations among species with small sporocarps and proto- or aphanoplasmodia. In contrast, litter-inhabiting species with phaneroplasmodia seem to avoid each other. Myxomycetes in the investigated winter-cold desert behaved as rather opportunistic k-strategists, quickly using all temporally and spatially changing microhabitats.