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155 rhizosphere soil and root mixtures were collected from under Ammophila arenaria colonizing maritime dunes of the island Bornholm (Denmark) to determine arbuscular mycorrhizal fungi (AMF) of the phylum Glomeromycota co-existing with this plant. In the laboratory, each mixture was divided into two parts. One part was used to establish a pot culture with Plantago lanceolata as the host plant to initiate sporulation of fungi that had not produced spores in field conditions. In the second part, the numerical and species composition of the spore populations of AMF sporulating in the field was determined. Spores of AMF were found in 70 fieldcollected samples and 134 trap cultures. They represented 26 species and six undescribed morphotypes in six genera of the Glomeromycota. Of them, 20 species and three morphotypes in five genera occurred in the field, and 16 species and three morphotypes in five genera were found in trap cultures. The fungi most frequently revealed were members of the genus Glomus; a total of 17 species and six morphotypes of this genus were recognized. Considering the occurrence of spores in both field samples and trap cultures, the fungi most frequently co-occurring with roots of A. arenaria growing in the dunes of Bornholm were G. irregulare (present in 73.6% of samples), followed by Scutellospora dipurpurescens (19.4%) and Archaeospora trappei (10.3%). However, Glomus irregulare mainly sporulated in trap cultures; spores of this fungus were found in only 0.6% of field samples. Other relatively frequently found species were G. aggregatum (9.0%), G. eburneum (7.1%), Paraglomus laccatum (5.2%), and S. armeniaca (6.5%). The species most abundantly sporulating in the field were G. aggregatum (produced 28.36% of all spores isolated), G. badium (11.00%), and S. dipurpurescens (21.55%).
A description is provided of Longidorus balticus sp. nov., a bisexual species recovered from the rhizosphere of Elymns arenarias L. growing in coastal sand dunes in northeast Poland. The species is characterized by having a long (L=6.7-9.2 mm) and slender (a= 119-175) body; expanded labial region, flattened anteriorly; assymetrically bilobed amphids; anteriorly situated guide ring (23-29 µm); odontostyle of medium length (91-105 µm); and a short, rounded tail. Males having spicules of medium size (58-69 µm), and a row of 9-15 supplements. Longidorus baltieus sp. nov. has four juvenile developmental stages. Longidorus balticus sp. nov. resembles L. vineacola, L. belloi, L. lusitaniens, L. moesicus, L. profundorum and L. apulus.
Numerous environmental factors are confirmed to have significant influence on the habitat choice of invertebrates and thus on the assemblage structure. In dry, sandy grasslands the vegetation cover and height are assumed to be the most important factors in shaping the distribution of spiders and true bugs. The present study was carried out at a natural sand dune area in the Kiskunság region of the Hungarian Great Plain. Two adjacent sand dunes and the dune valley between them were sampled using a transect consisting of pitfall traps. The traps were arranged in 4 parallel transects, running from the sand dune top through the dune valley to the adjacent sand dune. Each row consisted of 40 traps, three meters apart. The effect of microhabitat parameters on the species richness and abundance of invertebrate assemblages were tested with linear regressions with forward selection procedure. A total number of 1447 spider and 1580 true-bug individuals of 58 and 55 species were collected, respectively. The mean number of spider species along the transects was 10.5 ± 3.7 and 9.8 ± 3.0 for true bugs. Although our data did not show a significant effect of the plant species number on species richness and abundance of the two studied taxa along this gradient, the results of the canonical correspondence analysis and the Mantel test emphasized the importance of the total coverage and vegetation composition on the distribution of invertebrate species. The correspondence analysis and the multivariate ANOVA revealed different spider and true-bug assemblages on the two slopes (multivariate ANOVA: Araneae: F = 3.609, P <0.001, Heteroptera: F = 5.248, P <0.001), possibly due to the more dense and diverse vegetation on the north facing slope, which is presumably brought about by the different insolation and moisture conditions of the slopes.
Human-induced habitat changes have been typically linked to negative effects on native species, but an increasing number of studies show that many species are unaffected by these changes or even benefited from them. The Burrowing Owl Athene cunicularia is a raptor species that has deserved special attention in recent years due to its capacity to live in a variety of natural and modified habitats. In this study, we analyzed habitat characteristics that determine the habitat selection of the Burrowing Owl at the nest-patch, territory and landscape scales in the Pampas of Argentina. We performed broadcasting call surveys to evaluate presence-absence of owls at random points. In addition, we measured habitat variables in the field and used satellite imagery to obtain land-use information. We used Generalized Linear Models to explore the influence of habitat variables on the probability of occupancy by Burrowing Owls. Our results indicate that Burrowing Owls demonstrate good ability to live in a wide variety of habitat types and with different disturbance levels in the Pampas. At the nest-patch scale, which includes the nest-site and the surrounding patch around it, the presence of owls was positively associated with the horizontal visibility and was influenced by the land-cover type. At the territory scale, the occurrence of owls was positively associated with the presence of active (non-vegetated) dunes and negatively with croplands. At the landscape scale, the presence of owls was negatively associated with the disturbance level and positively with the amount of borders between habitats. A unique multi-scale model containing variables of the three spatial scales was more robust to explain variation in Burrowing Owl occupancy patterns than any single-scale model. This would reveal the hierarchical nature of habitat selection by Burrowing Owls in the Pampas, comparable to that observed in North American populations.
Scleroderma septentrionale Jeppson was fi rst discovered in Central Europe in the Puszcza Kampinoska primeval forest (Central Poland) over 40 years ago. We found two new inland localities of this rare species in southern Poland: on natural inland sand dunes of post-glacial origin (Pustynia Błędowska) and at an anthropogenic site on sandy soil polluted by heavy metals (Olkusz, in the vicinity of the Bolesław Mine and Smelter). The basidiocarps occurred under willow and birch or pine and birch. The new localities are approximately midway between two previously known inland stands in Central Europe (Puszcza Kampinoska forest and the Zahorie region in Slovakia).
Lasius psammophilus Seifert and Formica cinerea Mayr can both be found on sand dunes in high densities. Sometimes they even nest in each other's immediate neighbourhood, which implies the possibility of conflicts, and the existence of mechanisms for avoiding contest competition. In such case an appropriate method is the analysis of the distribution and behaviour of foraging individuals around their colonies in the absence and in the presence of baits. The results show that the higher foraging activity of L. psammophilus with lower temperature and higher humidity as compared to F. cinerea, as well as the lack of spatial interference assures a relatively peaceful coexistence even in the case of neighbouring colonies. While L. psammophilus is characterized by fortuitousness regarding the chances of discovering food sources, F. cinerea foragers search more thoroughly around their colonies. Conflicts can arise over large food sources, which conflicts are usually won by F. cinerea. However, the more efficient recruitment system of L. psammophilus (earlier start and higher intensity), allows this species dominate at clumped food patches when the climatic conditions are favourable. The possible ways of coexistence are discussed, as well as the species' positions in the competition hierarchy.
Phytosociological analysis of non-forest communities was carried out on one of the oldest and the biggest military training grounds in Europe, located near the city of Toruń, in central Poland. Heaths and psammophilous grasslands developed here as a result of deforestation of inland dunes in the valley of the Vistula River, as well as a result of destruction of soils and vegetation brought on by manoeuvres and artillery firings. They form a landscape mosaic with young self-seeding pines, mature pine forests and birch forests. Using the Braun-Blanquet method, 84 relevés were made in the areas dominated by dwarf shrubs and 32 relevés within psammophilous grasslands. Applying the classic phytosociological method, the following plant associations were distinguished in the first set of relevés: Pohlio-Callunetum and Arctostaphylo-Callunetum, as well as the community with Cytisus scoparius. Within the psammophilous grasslands, two associations were distinguished: Spergulo vernalis-Corynephoretum and Calamagrostietum epigeji. In this paper, the heterogeneity within associations and communities was presented together with descriptions of individual syntaxa, as well as dynamic and developmental relationships between the aforementioned were identified.
The Cryptoglossini (Coleoptera: Tenebrionidae: Pimeliinae) is revised. The species are relatively large beetles, which are irregularly distributed throughout much of the highly arid areas of Southwestern United States and Mexico. The tribe is composed of three monophyletic genera: Asbolus LeConte, Cryptoglossa Sober, and Schizillus Horn. Adult external and internal reproductive structures of the tribe are described and illustrated. Immature stages are described for Cryptoglossa muricata (LeConte), Cryptoglossa infausta (LeConte), Cryptoglossa asperata (Horn), Cryptoglossa spiculifera LeConte, Cryptoglossa variolosa (Horn), Asbolus verrucosus LeConte, Asbolus laevis LeConte, Asbolus mexicanus (Champion), Schizillus laticeps Horn, and Schizillus nunenmacheri Blaisdell. Keys are provided for the adult genera and species and for the known immature stages. A new subspecies, Cryptoglossa seriata cerralvoensis, is described from Mexico. Centrioptera Mannerheim is placed as a synonym of Cryptoglossa Sober. Asbolus LeConte is reinstated to replace Cryptoglossa (in part). Eschatoporis Blaisdell is removed to the Laenini (Lagriinae). A phylogeny, based on 50 adult and immature characters is proposed established on cladistic methodology. Phylogenetic relationships and systematic position of the subfamily, tribe, genera and species are examined. The biology of the species is discussed including ecological, morphological, and physiological adaptations to aridity. Ecological adaptations include strategies to acclimate to extreme environmental conditions: surface/subsurface daily and seasonal activity patterns, cavity utilization, substrate preference/restrictions (C. muricata, A. verrucosus, S. laticeps), euryphagous feeding habits, avoidance of interspecific competition. Adult and immature morphological adaptations include locomotory modifications relative to substrate utilization (i.e. larval madibular expansion in all Cryptoglossini) and heat avoidance modifications (i.e. subelytral/subpronotal cavities in A. verrucosus, A. laevis and A. papillosus. Physiological adaptations include high heat and wide humidity range tolerance (C. muricata and A. verrucosus), epicuticular lipids with high rations of straight-chain hydrocarbons (C. variolosa and A. verrucosus), long larval and adult life spans (seven years recorded for A. verrucosus). Specialized environmental adaptations include psammophily (A. verrucosus, A. papillosus and A. laevis, being respectively more adapted to psammophily, the last two restricted to sand dunes) and troglophily (S. nunenmacheri and A. mexicanus). Ecological importance (biomass) and economic importance of species is discussed. Predators and parasites of the Cryptoglossini are addressed. Catagoniopsis specularis (Aldrich and Weber), (Tachinidae) is recorded reared from both A. verrucosus and A. laevis. Defensive behavioral strategies include escape to shelters (Cryptoglossa), death feigning (all Cryptoglossa observed except C. asperata; most developed in Asbolus) and head standing (most immediate defense in all Cryptoglossa observed, absent in Asbolus and Schizillus except A. laevis).
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