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Amplified ribosomal DNA restriction analysis (ARDRA) was used to compare the bacterial communities of the food, the gut sections (ceca, anterior and posterior midgut, hindgut) and the excrement of the litter feeding bibionid larvae of Penthetria holosericea. For universal eubacterial primers ARDRA patterns were complex with only minor differences among samples. Taxon specific primers were also applied to characterize the samples. Fragment composition was transformed to presence/absence binary data and further analyzed. Cluster analysis revealed that bacterial communities of gut highly resembled each other with the exception of the ceca. ARDRA patterns of consumed leaves clustered together with the intact leaves but differed from those of the excrement. ARDRA results were compared with microbial community structure based on phospholipid fatty acid (PLFA) fingerprints. The cluster analysis of PLFA (presence/absence binary) data resulted in a pattern similar to the ARDRA data. The PCA analysis of PLFA relative content separated microbial communities into five groups: (1) anterior and posterior midgut, (2) hindgut, (3) ceca, (4) consumed and intact litter, (5) excrement. Both methods indicated that conditions in the larval gut result in formation of a specific microbial community which differs from both the food and excrement ones. Particularly ceca--(blind appendages, harbor very specific microbial community) are divided from the rest of the gut by perithropic membrane.

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The study compared communities of soil Collembola along the inversed microclimatic gradient of the collapse doline of the Silická ľadnica Ice Cave (Slovakia) in spring and autumn of 2005. Kruskal-Wallis ANOVA and the MannWhitney test revealed significant differences in abundance between sites and both seasons. Significantly higher abundance means and species richness were observed at most sites during the spring compared with the autumn. NMS ordination documented a clear delimitation of communities with remarkably different soil microclimates. The community pattern of the coldest section of the gradient, with low species richness and high mean abundance, was analogous to communities living in the harsh alpine and polar soils. The collapse doline with inversed microclimate hosted a high number of species (72) and a broad variety of montane forms (13), thus documenting that these karst landforms enhance local diversity of edaphic Collembola and serve as local refugia of specialized cold-tolerant species. The cold tolerance of the four abundant species at the doline cold sites, namely Ceratophysella sigillata, Tetrodontophora bielanensis, Protaphorura armata and Desoria tigrina, was tested in the laboratory using one-hour exposition survival tests. Within a temperature range from -2.4 to -7.8 • C, T. bielanensis was the most cold-sensitive species, with a lethal dose LD50 of -4.4 • C, while D. tigrina was the most cold-resistant, showing LD50 of -5.8 • C.

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Methane production by intestinal methanogenic Archaea and their community structure were compared among phylogenetic lineages of millipedes. Tropical and temperate millipedes of 35 species and 17 families were investigated. Species that emitted methane were mostly in the juliform orders Julida, Spirobolida, and Spirostreptida. The irregular phylogenetic distribution of methane production correlated with the presence of the methanogen-specific mcrA gene. The study brings the first detailed survey of methanogens’ diversity in the digestive tract of millipedes. Sequences related to Methanosarcinales, Methanobacteriales, Methanomicrobiales and some unclassified Archaea were detected using molecular profiling (DGGE). The differences in substrate preferences of the main lineages of methanogenic Archaea found in different millipede orders indicate that the composition of methanogen communities may reflect the differences in available substrates for methanogenesis or the presence of symbiotic protozoa in the digestive tract. We conclude that differences in methane production in the millipede gut reflect differences in the activity and proliferation of intestinal methanogens rather than an absolute inability of some millipede taxa to host methanogens. This inference was supported by the general presence of methanogenic activity in millipede faecal pellets and the presence of the 16S rRNA gene of methanogens in all tested taxa in the two main groups of millipedes, the Helminthophora and the Pentazonia.