Ips duplicatus (Sahlberg) is an important forest pest in central Europe, but its nematode associates have seldom been studied. Therefore, nematodes associated with I. duplicatus were determined at three localities in the Czech Republic. The percentage of beetles with phoretic nematodes ranged from 18 to 65%. Micoletzkya buetschlii and other phoretic nematodes were found under elytra, on wings, and between body segments. The percentage of beetles with nematodes in the haemocoel ranged from 3 to 30%, and the nematodes included Contortylenchus diplogaster and Parasitylenchus cf. aculeatus. Juveniles of Parasitorhabditis obtusa (Fuchs 1915) were found in the intestines of 0-16% of the beetles. The most abundant species in I. duplicatus galleries were P. obtusa and M. buetschlii. Cryptaphelenchus sp., Parasitaphelenchus sp. and unidentified tylenchid juveniles also were found in the galleries. The percentage of beetles with nematodes was greater in the overwintering than in the offspring generation, and numbers of nematodes per gallery increased with gallery development.

The ecological requirements and biology of the Tetrigidae are almost unknown. The aim of the present work is to contribute to the knowledge of Tetrix bolivari, one of the least studied species of European Tetrigidae, by investigating its seasonal and daily activity, food biology, and vibratory communication. Adults of T. bolivari were found from March to September, with the greatest number of detections occurring between May and August. Based on the study of the daily activity patterns, most activities were positively correlated with temperature and negatively correlated with relative humidity. Detritus and mosses were the main components of the diet, with the most frequently consumed mosses being Bryum caespiticium and Bryum argenteum. Substrate-borne vibrational signals used in communication of T. bolivari are described here in detail for the first time. We distinguished four structural types of vibrational signals produced by males, including the signal produced by wing tremulation.

Lukášová K., Holuša J., Grucmanová Š. 2012: Reproductive performance of univoltine population of Ips typographus (Coleoptera, Curculionidae) at epidemic level in Central Europe: case study of small-scale and short-term bark beetles outbreak in the Šumava Mts. -Beskydy, 5 (2): 153-162Population of I. typographus was studied in one locality with small-scale and short-term outbreak distant from large-scale and long-term outbreak area by several hundred meters. In total, ten spruce trees infested by the spruce bark beetle were examined. Always four stripes of bark (sample area) with the length equal to half the circumference of the trunk and the width of approximately 0.5 m were analyzed. The local spruce bark beetle population was characterized by high population density (1.5±1.2 entry holes per dm 2 ), low number of eggs per female, and short maternal galleries. Relatively low reproductive success (0.8 female offspring per one mother beetle, percentage of surviving individuals varies between 1and 18 % was documented. The parasitism rate of living developmental stages of spruce bark beetle by larval parasitoids averaged 14 %. The level of infestation by pathogens and endoparasitoids in maternal beetles from their galleries was low. Highly likely, it is a result of short-term outbreak during which response of parasitoids was delayed in time.

A study of nematodes associated with the large larch bark beetle Ips cembrae (Heer 1836) was carried out at three locations in the Czech Republic. The proportion of beetles infested by endoparasitic nematodes (representatives of genera Contortylenchus, Parasitylenchus, Cryptaphelenchus and Parasitorhabditis) ranged from 29.9 to 50.9%. Significant differences were determined in nematode infestation levels among locations, generations and sampling methods. No differences were found in infestation rates between males and females. The percentage of bark beetles with phoretic nematodes ranged from 18 to 42.9%. Phoretic nematodes directly found under elytra, on wings and between body segments of the bark beetles belong to the genus Micoletzkya. However, adults and juveniles of other two phoretic species Laimaphelenchus penardi and Bursaphelenchus sp. were found in the gallery frass of I. cembrae. Infestation by phoretic nematodes positively correlated with the presence of mites under elytra.

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