The habitat-suitability models of the European mole cricket (Gryllotalpa gryllotalpa) as information tool for conservation and pest management.

The European mole cricket, Gryllotalpa gryllotalpa, feeds on a wide range of crops and can also damage plants with its burrowing activities. In suitable habitats (like those with damp, rich soils in flood plains), G. gryllotalpa numbers can increase to high levels. On the other hand, the abundance of G. gryllotalpa has dramatically decreased in north-western Europe partly due to direct eradication and excessive pest control. Using habitat suitability modelling, we identified areas suitable for G. gryllotalpa occurrence based on previous reports of its occurrence and based on environmental data. We limited our study area to regions where G. gryllotalpa is the only known Gryllotalpa species. The most important variables in our models were found to be relative air humidity and minimum soil temperature of the coldest month. We suggest that soil temperature is a limiting factor for European mole cricket occurrence in the Czech Republic because most areas in the country experience soil temperatures just below 0 °C, while most reports of G. gryllotalpa occurrence in Europe are from areas where the soil temperature does not drop below 0 °C. The models we have developed can provide information on possible occurrences of the mole cricket and thus improve the decision-making process both in the field of pest control and the conservation of this species.

Comprehensive comparison of treatments for controlling the large pine weevil (Hylobius abietis) in Central Europe.

Adults of the large pine weevil (Hylobius abietis) cause serious damage to coniferous seedlings and are among the most important forest pests in Europe. Seedling protection by chemicals is gradually being restricted or banned for environmental reasons, and non-chemical alternatives are therefore needed. In this 3-year study, we compared the following five treatments for protecting Norway spruce seedlings against H. abietis in the Central European mountains where the weevil is especially abundant: alpha-cypermethrin sprays (the only chemical treatment); coating with sprayed glue (Vermifix); wax coating with C and F types (Norsk Wax); and physical protection with collars. The same block design was set up at a clear-cut site and at a nursery site to compare seedling mortality and wax quality under "wild conditions" with pests and under "ideal conditions" without pests. Repeated application of alpha-cypermethrin was the most effective and least expensive method to protect seedlings against H. abietis. Among the four non-chemical methods, repeated application of glue was the most effective. Because collars were moderately effective but not cost-effective, we do not recommend the use of collars. Wax was inexpensive and environmentally safe but protected seedlings for only 1 year; the newer F type of wax performed better than the C type of wax, and perhaps the F type can be improved. In general we found that seedlings at sites with high numbers of H. abietis require protection for at least 3 years. We conclude by providing an overview of all methods currently available for managing H. abietis in forests.

Relationships between the fecundity of bark beetles and the presence of antagonists.

Although previous research has documented the occurrence of antagonists of bark beetles, the studies have only evaluated individual antagonists and have not assessed the overall effect of all antagonists on adult beetles. In this study, we determined which body-cavity antagonists were associated with a reduction in the fecundity and maternal gallery lengths of two important species of bark beetles: Ips typographus on Norway spruce and I. cembrae on European larch. We evaluated these relationships under natural conditions by collecting maternal females in galleries and examining their internal organs. The antagonists in the I. typographus hemolymph had significant negative associations with fecundity and gallery length. These antagonists were mainly nematodes and parasitoids in the hemocoel. In contrast, a positive association between gregarine presence and I. typographus fecundity was found. No antagonist that was likely to significantly alter I. cembrae fecundity or maternal gallery length was proven. Our study provides the first comprehensive assessment of antagonists that may have the potential impact on reduction the fecundity and thereby mass occurrence of these bark beetles.

The Bark Beetle Phloeotribus rhododactylus (Coleoptera: Curculionidae) Has a Stable Range in Europe.

The bark beetle Phloeotribus rhododactylus feeds mainly on the shrub Cytisus scoparius. The range of P. rhododactylus extends from Spain in the south to southern Sweden, Denmark, and Scotland in the north. Its range to the east extends to Poland, Slovakia, and Hungary, but single localities are known further east in Romania, Bulgaria, and Greece. It is clear that the range of the beetle matches that of its main host. C. scoparius is adapted to Mediterranean and coastal climates, and its range is limited by low winter temperatures. P. rhododactylus is, therefore, rare in Central Europe. It infests either individuals of C. scoparius that have been damaged by mammalian herbivores or snow or that are drought-stressed. Although C. scoparius is an invasive plant in agricultural and natural ecosystems, P. rhododactylus has not been found in any of the areas where C. scoparius has invaded.

Estimates of phoretic mite abundance on bark beetles as affected by beetle capture method: a case study with Mesostigmata mites and Ips typographus (Coleoptera: Curculionidae).

The spectrum of Mesostigmata mite species that are phoretic on the bark beetle Ips typographus has been well described. However, phoretic mite abundance has mostly been quantified by researchers who used only a single method for capturing bark beetles: pheromone traps. We therefore compared mite abundance using two beetle-capture methods. At a single location with high numbers of I. typographus in the eastern Czech Republic in 2013, beetles were collected with pheromone traps and from infested logs placed in emergence traps. In total 29,589 I. typographus beetles were captured using the two methods. Mite abundance was assessed on 2400 beetles from pheromone traps and on 955 beetles from emergence traps; in total 5805 phoretic mesostigmatid mites were detected. Six species of phoretic mites were captured using pheromone traps and four species using emergence traps. The number of phoretic mites per beetle was higher for beetles captured in emergence traps than for beetles captured in pheromone traps. The most abundant mite species overall were Dendrolaelaps quadrisetus, Uroobovella ipidis, and Trichouropoda polytricha. The seasonal dynamics of phoretic mites paralleled the seasonal dynamics of their hosts.

Microclimatic conditions of Lasius flavus ant mounds.

Like other organisms, ants require suitable microclimatic conditions for their development. Thus, ant species inhabiting colder climates build nest mounds that rise above the soil surface, presumably to obtain heating from solar radiation. Although some ant species construct mounds of organic materials, which generate substantial heat due to microbial metabolism, Lasius flavus mounds consists mostly of soil, not organic material. The use of artificial shading in the current study demonstrated that L. flavus depends on direct solar radiation to regulate the temperature in its mound-like nests. Temperatures were much lower in shaded mounds than in unshaded mounds and were likely low enough in shaded mounds to reduce ant development and reproduction. In areas where L. flavus and similar ants are undesirable, they might be managed by shading.

Occurrence of Microsporidium sp. and other pathogens in Ips amitinus (Coleoptera: Curculionidae).

A new microsporidium is reported from the small spruce bark beetle, Ips amitinus: Microsporidium sp. with uninucleate oval spores measuring 3.5 × 2.5 µm; infecting cells of the midgut epithelium, midgut muscles, the fat body, the Malpighian tubules, and the gonads of adult beetles collected in Austria. Seven other pathogens were found in beetles collected from Austria, the Czech Republic, and Finland. Six of them were already known from I. amitinus. Nosema cf. typographi is recorded for the first time in the overwintering generation of I. amitinus from the Czech Republic.

The role of geography and host abundance in the distribution of parasitoids of an alien pest.

Chalcid wasps (Hymenoptera: Chalcidoidea) are probably the most effective and abundant parasitoids of the horse chestnut leaf miner (Cameraria ohridella), an alien pest in Europe that lacks specialized enemies. We studied how the species richness and abundance of chalcids are influenced by altitude, direction of an alien spread and host abundance of C. ohridella. We quantified the numbers and species richness of chalcid wasps and the numbers of C. ohridella that emerged from horse chestnut (Aesculus hippocastanum) leaf litter samples collected from 35 sites in the Czech Republic. Species richness of chalcids, which was considered an indicator of the possible adaptation of parasitoids to this alien host, was unrelated to C. ohridella abundance, direction of spread, or altitude. Chalcid abundance, which was considered an indicator of parasitism of the alien host, was strongly and positively related to C. ohridella abundance. Chalcid abundance was negatively related to direction of spread and positively related, although in a non-linear manner, to altitude. The relationship of chalcid abundance with direction of spread and altitude was weaker than that with C. ohridella abundance. The results provide evidence that biological control of the alien pest C. ohridella by natural enemies might develop in the future.

Comparison of pathogens infection level in Ips typographus (Coleoptera: Curculionidae) beetles sampled in pheromone traps and at place of overwintering.

The importance of pathogens in the population dynamics of Ips typographus remains a subject of ongoing debate. The main objective of our experiment was to compare the pathogen infection levels of individuals overwintering in bark with the levels of individuals from the same population captured with pheromone traps and thereby to determine primary answers as to whether it can be confirmed that pathogenic organisms affect the flight ability of bark beetles or their ability to leave their places of overwintering. A total of 402 I. typographus individuals were analyzed at a study location under limited management. Three pathogens were confirmed to be present: the gregarine Gregarina typographi, the virus ItEPV, and the microsporidium Nosema typographi. Infection levels of Gregarina typographi and ItEPV were the same in beetles collected at places of overwintering and in those beetles collected in pheromone traps within the immediate vicinity. As these pathogens infect the host's intestine, the tendency to leave the places of overwintering is apparently not diminished. A similar analysis and comparison of pathogens located in the fat body might bring different results, as our study only detected N. typographi in a single dissected adult spruce bark beetle.

Annotated checklist of the grasshoppers and crickets (Orthoptera) of the Czech Republic.

A checklist is presented of the Orthoptera of the Czech Republic. Based on the critical revision of published data and previous lists of species, which often contained only general or questionable data and which often inaccurately cited each other, we found 96 species of Orthoptera belonging to the fauna of the Czech Republic. We emphasize those changes that are based on comparison with previous checklists. We provide information on missing, unclear, and extinct species and on newly detected species, and we confirm the status of species that have been missing for a long time (Leptophyes boscii, Polysarcus denticauda, Ruspolia nitidula, Eumodicogryllus bordigalensis, Tetrix bolivari, Mecostethus parapleurus). We also note those species for which only several individuals have been detected (Pteronemobius heydenii) or those survived only at a single locality (Platycleis montana, Aiolopus thalassinus, Dociostaurus brevicollis, Omocestus petraeus) or at two localities (Poecilimon intermedius, Platycleis veyseli, Pseudopodisma nagyi). Phaneroptera nana is recorded as new for Bohemia.

Liberomyces gen. nov. with two new species of endophytic coelomycetes from broadleaf trees.

During a study of endophytic and saprotrophic fungi in the sapwood and phloem of broadleaf trees (Salix alba, Quercus robur, Ulmus laevis, Alnus glutinosa, Betula pendula) fungi belonging to an anamorphic coelomycetous genus not attributable to a described taxon were detected and isolated in pure culture. The new genus, Liberomyces, with two species, L. saliciphilus and L. macrosporus, is described. Both species have subglobose conidiomata containing holoblastic sympodial conidiogenous cells. The conidiomata dehisce irregularly or by ostiole and secrete a slimy suspension of conidia. The conidia are hyaline, narrowly allantoid with a typically curved distal end. In L. macrosporus simultaneous production of synanamorph with thin filamentous conidia was observed occasionally. The genus has no known teleomorph. Related sequences in the public databases belong to endophytes of angiosperms. Phylogenetic analysis revealed a position close to the Xylariales (Sordariomycetes), but family and order affiliation remained unclear.