(Col. Blateridae) Av AxB llon<; Slatens vdxtskyddsanstalt, S-532 00, Skara, Sweden Abstract Bonc, A. Iixperiments with heap traps for catching click beetles (Col. Elateridae). - Ent. Tidskr. 96: 29-36, 1975. The occurrence of elaterids (adults) in arable land in Vflstergritland (Western, Central Sweden) has been investigated with the help of heap traps. Cerlain experiments have been carried out also in Northern Sweden (Teg, UmeA). Other melhods for catching elaterids have also been tested or are discussed. The material in the heap traps consisted in the first years of grass and herbs obtainable in the test field, later on of hay, which is advantageous if the traps are to be set early in the season. A total of 6,186 elaterids, representing 9 species, were taken in the traps. The species nrost abundantly representcd tl'ere: Agriotes /ineatus L., A. obscurus L. Hgpnoidus riparius!-. and Limonias aeruginosus Ol. Judging from the catches. obscurus was the dominant Agriotes species in habitats on mineral soils, 'n'hile both Agriofes species might be found in about equal abundance in habitats on organic soil. A. lineatus, however, was the predominant species on a Lriotope with pronouncedly organic soil. The two Agriotes species emerged, according to the catches, in May or, when spring came early, in the middle of April (ftneafus). Males and females of lineatus emerged at the same time and appeared in about the same number. Of 4,897 lineatus specimens captured in heap traps, 49.9 per cent were females.
.ErB sonc I entrt I Procent.4griotes lineatus L...... A. obscurus L.... ::. Atltous sub/uscus }Itill.... Corgmbites aeneus L.... C. incanus (quercus) Gyll... C. pectinicornis L... C. tesselotus L..... Dolopius marginatus L..... Elater bolteatus L.. Hgpnoidus ripurius F..... Limonius neruginosus OI...
FCiRsoK MED HOFALLoR F6R F.&NGsr AV KNippARSKALBAGGAR Tabell l. Fingst av elaterider med vixtfiillor. Table 1. Captures of elaterids in heap traps. Antal (No. of) \Iaterial i fiillorna Traps nraterial Antal elater. No. of date/month elaterids havre, korn, rag havre, korn, vall vall havre, korn potatis korn, potatis korn, potatis rag havre vall vall havre havre griis, korn, 28/5-1/7 havre
32 Are nonc Tabell 2. FAngst av elaterider med vfixtfillor. Table 2. Captures of elaterids in heap traps.
TORSOK MED rrof;illor FOR FANGST Av KN;ippARSKALBAGGAR Tabell 3. Kiinskvot hos A. Iineafus och obscurus tagna i hrifiillor. Table 3. The sex ratio of A. lineatus and obscurus captured in heap traps. Plats, ir Site, year A. lineatus Hanar' I I{onor Males Females o/o Honor Females A. obscurus Hanar Honor Males Females olo Honor Females Agriotes obscurus..,.. A. lineatus...:::: Limonius aeruginosus,,.,. Hgpnoklus riporius Corgmbites eeneus. Athous subluscus A. lineatus Nlineraljord \Iulljord Antal I Procent
AxB sonc I rin""t,"! "r",-" l0 Junl(June )
FoRSOK MED IIOFALLOR F6R FANGST AV KNAPPARSKALBAGGAR 10 4 Mal(iley) Juni(Jun ) Jult(July) Fig. 1-{. F{ngst av elatrider i h<ifilllor. - l. Agriotes obscurus, Bj6rsgArden, Vinninga 1962. 2. A. obscurus, Teg 1968. 3. A. obscurus och A. Iineatus, Dagsniis 1968. {. A. linetttus, Stenunr 1971. Max- och minimitemperatur mellan kl. 19.00-07.00, Skara, 1,5 m ovan markytan samt nederbiird. Figs. 1--1. Captures of Elaterids in heap traps. Max. and min. temp. at Skara 19.00-07'00 o'clock, 1.5 m above ground and precipitation.
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