Hans Peter Ravn

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The arrangement of antennal sensilla was studied in female and male ground beetles Bembidion properans Steph. (Coleoptera, Carabidae) using scanning electron microscopy. The filiform antennae, 1.8-1.9 mm in length, consist of the scape, pedicel and nine flagellomeres. In both sexes, three types of sensilla chaetica, two types of sensilla trichodea, six(More)
The antennal sensilla of male and female Hbst., Bembidion properans Steph. and Platynus d investigated by using a scanning electron microscop consist of the scape, pedicel and 9 flagellomere distiguished. These were: four types of sensilla ch types of sensilla basiconica, pit-organs sensilla campaniformia. Sensilla chaetica 4 occur only on trichodea 1 only(More)
The capacity of small urban park to serve as urban habitats are rarely explored. This study analyses the characteristics of small urban parks and their potential to support urban biodiversity and ecological functions. Nine small urban parks were studied in Malaysia in August and September 2014 using the combined field survey method of structured observation(More)
The harlequin ladybird, Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae), is native to Asia but has been intentionally introduced to many countries as a biological control agent of pest insects. In numerous countries, however, it has been introduced unintentionally. The dramatic spread of H. axyridis within many countries has been met with(More)
Citation: Groom QJ, Adriaens T, Desmet P, Simpson A, De Wever A, Bazos I, Cardoso AC, Charles L, Christopoulou A, Gazda A, Helmisaari H, Hobern D, Josefsson M, Lucy F, Marisavljevic D, Oszako T, Pergl J, Petrovic-Obradovic O, Prévot C, Ravn HP, Richards G, Roques A, Roy HE, Rozenberg M-AA, Scalera R, Tricarico E, Trichkova T, Vercayie D, Zenetos A and(More)
In aphidophagous insect communities invaded by the harlequin ladybird Harmonia axyridis Pallas (Coleoptera: Coccinellidae), intraguild predation (IGP) is widely implicated in the displacement of native predators, however, indirect trophic interactions are rarely assessed. Using molecular gut-content analysis, we investigated the relative frequencies of IGP(More)
The effect of cypermethrin and dimethoate exposure on soil-dwelling beetles, in spring barley at different growth stages, of doses of up to eight times maximum field application rate has been investigated. Doses up to eight times maximum field application rate of cypermethrin did not have any acute effects on larger beetles, such as P. melanarius and C.(More)
Occurrence of entomopathogenic fungi on phylloplanes in Tilia × europaea crowns between 1 and 13 m was assessed in urban parks. Prevalence of fungal infections in ladybirds (Coleoptera: Coccinellidae) collected from Tilia × europaea was assessed to determine whether fungi found on phylloplanes also occurred as infections in ladybirds. Isaria spp. was most(More)
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