Full-text - Norsk entomologisk forening

number ofsegments ofthe antennal flagellumis only five (rarely six according to Freeman& Lane, 1985) compared to seven or more inmost other Bibio species. This makes it fairlyeasy to distinguish B. nigriventris from otherNorwegian Bibio species. The body is blackin both sexes. The coxae of the male and thefemora are black, at least the last pair oftibiaare reddish brown. The legs ofthe females aremore brighter reddish-yellow. The frontwing-ribs are dark in both sexes. The last partof the male wings including the ribs is milkywhite, all wingsribs in the last part of thefemale wing, however, is dark and contrasting.The stigma of the male wing is not verydistinct, and only touching the margin of thewingfront in a smaller part. The stigma isdistinct in the female wing. B. nigriventrislarvae may damage roots of larch.EiFig. I. The distribution of Bibio nigriventris Halidayin Norway. Closed circles represent materialseen by the author. Open circle represents publishedrecord, material not seen by the author.ditional Bibionidae material hall been collectedin the last ten years by other methods likelighttraps, Malaisetraps, pitfalltraps and watertraps(yellow trays). Some of the trapshave been collecting all through the summerseason.Morphological charactersB. nigriventris has a body length 6--8 mmand is thus a middle sized Bibio species. TheEarlier records of B. nigriventris0, Halden: Hvaler (Strand, E. 1913). Thismaterial is today not present in Norwegiancollections. Siebke (1877) records B. nigriventris,1