Diversity of nivicolous myxomycetes of the Teberda State Biosphere Reserve (Northwestern Caucasus, Russia)

Abstract

Nivicolous myxomycete assemblages were surveyed on the northwest of the Greater Caucasian ridge in May-June 2010 and 2011 at a north facing transect between 1,700 and 2,920 m elevation of the summit Malaya Khatipara situated within the Teberda State Biosphere Reserve. Morphological characters of 396 collections representing 45 taxa (39 species, 3 varieties, and 3 forms) of myxomycetes in 8 genera and 5 families were recorded. Many (13) taxa are classified as rare (a species represents <0.5 % of all records). Only seven species were found to be widely distributed (present in 50 % or more of the 17 studied localities). To confirm the assignment of specimens to morphospecies, we obtained independently from determination 145 partial sequences of the 18S SSU rRNA gene from 35 taxa of Lamproderma, Meriderma, Physarum and Diderma, which turned out to represent 58 genotypes. Most of the taxa represented by more than one sequence had several genotypes, with an average of 1.7 genotypes per taxon. Except for three taxonomically difficult groups of species, partial SSU sequences did well correspond with the respective morphospecies and where similar or identical to sequences of specimens from the European Alps, making this marker a good candidate for barcoding in myxomycetes. Species richness and diversity increased from subalpine crooked-stem birch forests (23 species, 2 varieties, H′02.8, E00.88, D00.08) to alpine dwarf shrub communities (34 species and 2 varieties, 2 forms, H′03.2, E00.89, D0 0.05) but decreased again for alpine meadows (27 species and 2 varieties, 2 forms, H′03.1, E00.91, D00.06). Species richness and alpha-diversity reached maximum values for ground litter, whereas leaves and stems of living shrubs above ground harboured a more depauperate myxomycete assemblage.

Meriderma species (Myxomycetes) from the Polish Carpathians: a taxonomic revision using SEM-visualized spore ornamentation

“…Research of Fiore-Donno et al [12], supported this idea, indicating that delimitation of M. carestiae, M. cribrarioides, and M. aggregatum seems to correlate with phylogenetic analysis based on the SSU sequences. As well established, molecular analysis provides a promising methodology to clarify as well as verify taxonomic positions of many genera and species [12,13]. This combinational approach could successfully resolve taxonomic problems and properly indicate inter-and intraspecific variability within this group.…”

“…All so far recognized Meriderma species are present mainly in Europe, the Alps [1,14]. Six of them have recently been reported from the Caucasus [13] and five from the Khibiny Mountains [25]. Three species, M. aggregatum, M. carestiae, and M. spinulosporum are known from the Andes in South America [23], however, the first and the last slightly deviating in spore ornamentation.…”

“…From ecological point of view, Meriderma is a strictly nivicolous myxomycete genus [1][2][3]6,10], forming sporocarps during relatively short periods of time (late spring and early summer) at the margins of melting snow patches [13]. Sporocarps can be found on almost all accessible organic substrates [6].…”

Differentiation of some myxomycetes species by ITS sequences

“…The primary problem is the difficulty of isolating DNA from sporophores without cross-contamination. Although DNA isolation from a single sporophore (Martín et al, 2003) and use of only mature and distantly separated colonies of myxomycetes (Novozhilov et al, 2013) were reported to be successful in eliminating cross-contamination, the universal DNA databases are dominated by rDNA sequences from 7 different genera of myxomycetes. This is why it is very challenging to develop primers by using published sequence data from conserved rDNA genes of related myxomycetes species.…”

Genetic barcoding of dark‐spored myxomycetes (Amoebozoa)—Identification, evaluation and application of a sequence similarity threshold for species differentiation in NGS studies

“…To minimize cross‐contamination, the precautions described in Novozhilov et al. () were applied during sampling and isolation of the sporocarps. DNA was extracted according to manufacturer's protocol by either the Stratec Invisorb Spin Plant Mini Kit (Berlin, Germany), the Qiagen Plant kit (Hilden, Germany) or OMEGA Plant Kit (Norcross, Georgia, USA).…”