Vladimir Sustr

Biology Centre CAS, České Budějovice, Czech Republic · Institute of Soil Biology

Invertebrate–microbial associations are widespread in the biosphere and are often related to the function of novel genes, fitness advantages, and even speciation events. Despite ~ 13,000 species of millipedes identified across the world, millipedes and their gut microbiota are markedly understudied compared to other arthropods. Exploring the contri...

As important decomposers of soil organic matter, millipedes contribute to lignocellulose decomposition and nutrient cycling. The degradation of lignocellulose requires the action of several carbohydrate-active enzymes (CAZymes) and, in most invertebrates, depends on the activity of mutualistic gut microorganisms. To address the question of the impo...

We studied the fermentation pattern of the ciliate Nyctotherus velox grown in vitro with an unspecified bacterial population. The facultative anaerobic ciliates were isolated from the hindgut of the African tropical millipede Archispirostreptus gigas and cultivated for several months in vitro. We used the in-vitro gas technique to measure the ferme...

The middle region of the digestive system of millipedes, the midgut, is responsible for all processes connected with digestion, but also takes part in homeostasis maintenance thanks to the ability to activate many mechanisms which neutralize changes occurring at different levels of the animal’s body. Numerous millipede species are treated as bioind...

Methanogens represent the final decomposition guild in anaerobic degradation of organic matter, occurring in digestive tract of various invertebrates. However, factors determining their community structure and activity in distinct gut sections is still debated. In this study, we focused on the tropical millipede species Archispirostreptus gigas (Di...

Trophic niche differentiation may explain coexistence and shape functional roles of species. In complex natural food webs, however, trophic niche parameters depicted by single and isolated methods may simplify the multidimensional nature of consumer trophic niches, which includes feeding processes such as food choice, ingestion, digestion, assimila...

The trophic niche of an organism is tightly related to its role in the ecosystem and to interactions with other species. Thousands of species of soil animals feed on detritus and co-exist with apparently low specialisation in food resource use. Trophic niche differentiation may explain species coexistence in such a cryptic environment. However, mos...

Up to the present, the genus Archiboreoiulus included only two species: A. sollaudi from France and A. pallidus with a wide European distribution range. Here we describe a previously unknown species of the genus Archiboreoiulus, A. serbansarbui, collected from the mesothermal sulfurous Movile Cave, Mangalia, Romania, harboring a rich and diverse tr...

The release of greenhouse gases from millipede digestive tracts warrants study because of its potential effect on climate change and also as an indicator of microbial processes that transform organic matter during passage through the gut of these animals. Gas chromatography was used to quantify the release of methane (CH4), carbon dioxide (CO2), an...

This study investigated the effect of different plant litter types and developmental stages of the cockroach species Blaptica dubia on food consumption, animal growth, and excrement production. Three leaf litter species Alnus glutinosa, Acer platanoides, and Quercus robur were selected as model plants in a microcosm test in which plant litter was c...

We hypothesized that trogloxenes inhabiting surface habitats, thermally fluctuating environment, would tolerate wide temperature ranges. We expected that the temperature tolerances would diminish over categories trogloxene - subtroglophile - eutroglophile - troglobiont as a result of the degree of adaptation to subterranean environment that is char...

Vermicomposting is a process of degradation of biowaste which involves complex interactions between earthworms and microorganisms. This process lacks a thermophilic stage and thus, the possible presence of pathogens poses a potential health hazard. To assess the contribution of earthworms during the selective reduction of various pathogens, apple p...

The activity of enzymes associated with digestion can reflect food availability and feeding preferences of invertebrates in a particular habitat. Caves are mostly nutrient-poor habitats lacking primary production. In the present study the enzymatic activity of cellulases, trehalases and chitinases was measured in eight collembolan species different...

The hepatic cells are characteristic cells that occur in millipede body where they form a continuous layer which surrounds the midgut epithelium. The following species, which represent five millipede orders were selected: Julus scandinavius (Julida), Polyxenus lagurus (Polyxenida), Polydesmus angustus (Polydesmida, Polydesmidae), Strongylosoma stig...

During the winter, bats use hibernation as a means of surviving the period of low prey offer. However, the Mediterranean horseshoe bat (Rhinolophus euryale) arouses from torpor quite frequently. Based on the actual climatic conditions, it can profit from occasional foraging oportunities, when they occur. We analysed faeces collected on four nights...

According to the aim of the study, it is important to select the appropriate methodological approach. In taxonomical investigations, the high resolution of SEM serve important benefits, for morphofunctional research the nano CT represents the progressive method.

Folsomia manolachei Bagnall, 1939 (Collembola), is a widespread and common European species. However, it may represent a complex of species also associated with the climatically more extreme environments of the karst landforms. Three species of the genus Folsomia, distributed in the Slovak Karst region (Central Europe), namely three different popul...

The authors present the first record of the springtail Lipothrix italica (Hexapoda: Collembola) in the Romanian fauna. Notes on the taxonomic status, morphology, distribution and ecology of the species are given.

The mouthparts, labrum, maxillipeds, maxillae, maxillules, paragnaths and especially the mandibles, play very important role in the taxonomy and systematics of the Crustacea in general, and of the Oniscidea in particular. However, the classic studies, although supported by modern methods such as SEM, are destructive and in most cases, do not allow...

The body surface of the terrestrial isopod Mesoniscus graniger (Frivaldsky, 1863) showed blue autofluorescence under UV light (330–385 nm), using epifluorescence microscopy and also in living individuals under a UV lamp with excitation light of 365 nm. Some morphological cuticular structures expressed a more intense autofluorescence than other body...

As caves represent an extreme biotope with limited food sources, one might expect cave animal communities to exhibit low feeding specialization and to consume generally whatever organic matter is available. To test this hypothesis, we studied the feeding habits of several arthropod species in Slovakian and Roma-nian caves. A microanatomical approac...

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 Mann-Whitney test revealed significant differences in abundance between sites and both seasons. Significantly higher abundance means...

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 phyloge...

The authors provide a SEM description of the integument of Haplophthalmus movilae

The saprophagous larvae of bibionid flies harbor bacteria in their alkaline intestinal tracts, but little is known about the contribution of the gut microbiota to the digestion of their recalcitrant diet. In this study, we measured oxygen and hydrogen partial pressure, redox potential and pH in the midgut, gastric caeca and hindgut of larvae of the...

The autors provide a detailed description of the integumentary structures of Trachelipus troglobius

Earthworms Eisenia andrei, similarly to other invertebrates, rely on innate defense mechanisms based on the capability to recognize and respond to nonself. Here, we show a correlation between the expression of CCF, a crucial pattern-recognition receptor, and lysozyme, with enzyme activities in the gut of E. andrei earthworms following a microbial c...

The arboricolous dolichoderine ant Liometopum microcephalum (Panzer, 1798) is considered to be mainly predatory, although there are some reports of it tending aphids. The main objective of the present study was to confirm that this ant has a trophobiotic relationship with aphids and assess seasonal differences in its utilization of honeydew. We hyp...

SEM microscopy and multi-choice laboratory tests are used to investigate the feeding ecology of Mesoniscus graniger

This is the first study of the morphological structures on the integument of Mesoniscus graniger and the first record of auto-fluorescence under UV at this species

The water-physical properties (bulk density, air conductivity, texture, water content, and temperature dynamics) were studied in a chronosequence of soils developing on self-overgrowing quarry-dump complexes in the area of Sokolov, Czechia. The area overgrown for 12 years was covered by a thin grass cover; osiers were observed after 20 years of ove...

Authors describe the mouthparts of Mesoniscus graniger using SEM and infer about the systematic position of the family Mesoniscidae

The thermal preferences in a grain mass and respiration at various temperatures in mites (Acari: Acarididae) of medical and economical importance [Acarus siro (L. 1758), Dermatophagoides farinae Hughes 1961, Lepidoglyphus destructor (Schrank 1871), and Tyrophagus putrescentiae (Schrank 1781)] were studied under laboratory conditions. Based on the d...

Ontogenetic changes and temperature dependency of respiration rate were studied in Dendrobaena mrazeki, an earthworm species inhabiting relatively warm and dry habitats in Central Europe. D. mrazeki showed respiration rate lower than in other earthworm species, < 70 μl O2 g−1 h−1, within the temperature range of 5–35°C. The difference of respiratio...

Dendrobaena mrazeki is an endemic earthworm species inhabiting dry habitats such as pine and thermophilous oak forests in Central Europe. Metabolically, D. mrazeki showed some features typical for endogeic species and some of epigeic ones. In comparison with the related Dendrobaena octaedra, D. mrazeki was a larger earthworm with fresh body mass of...

The potential for methane production was investigated in 47 species of soil invertebrates. No detectable methane production was found in slugs, earthworms, potworms, oribatid mites, woodlices, springtails, centipedes, ants and soil diptera larvae. However, significant methane production was found in several temperate millipedes including some speci...

The ability of the physiological compensation of respiration rate and feeding activity for temperature was tested in oribatid mite Galumna elimata to evaluate significance of the increase of amylolytic activity in the whole body homogenates of mites exposed to cold acclimation. Mites were reared on green bark algae (Protococcus viridis) at differen...

In shallow subarctic ponds Daphnia and their algal food are often exposed to solar ultraviolet radiation (UVR). It was previously demonstrated that direct expo-sure of Daphnia to UVR may result in sublethal damage to Daphnia's intestinal sys-tem. This led to the hypothesis that, as consequences of such exposures, Daphnia may be experiencing a situa...

Feeding biology and thermal adaptations of the terrestrial isopod Mesoniscus graniger were studied. M. graniger is a depigmented isopod mainly inhabiting cave systems, although it has also been reported in endogeic (soil) habitats. Physiological adaptations are expected to reflect the unique environmental characteristics of caves, including restric...

Cellular fatty acid screening (MIDI System) of 93 bacterial strains isolated from the Domica Cave in the Slovak Karst region (Slovakia) showed that three bacterial strains (Chryseobacterium sp., Enterobacter amnigenus, Rhodococcus sp.) produce polyunsaturated fatty acids (PUFA) 18:3ω6 and 20:4ω6. These species (along with a non PUFA producer, Rhizo...

The abundance of oribatids in natural biotopes in the temperate region is characterised by two peaks, in spring and in autumn. We tested, whether these abundance peaks are accompanied by high feeding activity of Galumna elimata population. The defecation was used as an indirect estimation of the feeding activity. The model of seasonal changes of po...

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 a...

To elucidate the interaction between bacteria and saprophagousDiptera larvae, the amounts of bacteria in leaf litter, individual gut compartments, and feces of three species ofBibionidae (Bibio pomonae, Bibio marci, andPenthetria holosericea), feeding either directly on leaf litter or on fecal pellets produced from leaf litter by larvae of the same...

To describe the compartmentalization of the gut and the microbial activity in the digestive tract, the histology of the gut wall, enzymatic activity, pH of the gut content, abundance and composition of the microbial community (direct counts, plate counts on various media, and phospholipid fatty acid analyses—PLFA) were studied in the Penthetria hol...

Dipteran larvae play an important role in the soil of some deciduous forests. They can consume a considerable part of the annual litter fall and produce a large amount of faecal pellets, which are forming an important part of the fermentation horizon of forest soils. We measured the pH changes and assayed the activities and pH optima of saccharolyt...

The physiological parameters mortality, mass, oxygen consumption and amylase activity, and microanatomical features of the digestive tract, mesenchym and reproductive organs were used to characterise starvation in Galumna elimata. The mites were reared in sterilised plastic vials containing moistened zeolite at 25°C and a 12:12 photoperiod. The con...

Food selection of Scheloribates laevigatus was tested. Leaf litter (Holcus lanatus), filter paper, green algae (Protococcus spp.) and fungal spores (Penicillium griseofulvum) were offered for consumption. Starved individuals and individuals extracted directly from soil were observed. Food preference tests, microanatomy, enzyme tests and faecal pell...

The oribatid mite Galumna elimata was reared under laboratory conditions on algae (Protococcus spp.) at different temperatures (5, 15 and 20°C). Higher weight-specific amylolytic activity was found in the whole body homogenates of mites exposed to cold acclimation (5°C, 21 days) in comparison with individuals acclimated to 15 and 20°C. Accompanying...

Amylolytic activity was measured in whole body homogenates of High Arctic (Onychiurus arcticus) and temperate (Protaphorura armata) springtails (Collembola: Onychiuridae) in the temperature range 5-55 degrees C. A pH of ca. 8 was optimum for amylolytic activity in both species. A higher weight-specific amylolytic activity was observed in P. armata....

The effects of simulated acid rain and acidification, combined with liming, on amylolytic, laminarinolytic and xylanolytic activity in whole body homogenates of enchytraeids Cognettia sphagnetorum were studied under field conditions. Simulated acid rain (pH 2.5) and simulated acid rain with subsequent liming (CaCO3) were applied to experimental plo...

Amylolytic, xylanolytic, laminarinolytic, trehalolytic and cellulolytic activities were investigated in whole body homogenates of two potworm species Enchytraeus crypticus and Cognettia sphagnetorum. Amylolytic and trehalolytic activities were higher in E. crypticus than in C. sphagnetorum. In contrast, a higher xylanolytic activity was observed in...

Responses to elevated CO2 concentrations (up to 60 vol. %) were studied in a set of 19 species of soil invertebrates belonging to the Enchytraeidae, Lumbricidae, Isopoda, Diplopoda, Collembola and Insecta. Visible behavioural reactions, from changes of movement coordination to temporary paralysis, were observed at concentrations from 2 to 39 vol. %...

CO2 output in Tetrodontophora bielanensis was measured in the temperature range 0 to 20°C using gas chromatography after acclimation to 5, 13 and 19°C in the laboratory. The effect of acclimation temperature on mean CO2 output was not significant. The relationship between respiration and experimental temperature was found to very depending on the a...