Full-text - Norsk entomologisk forening

Helophilus 435Fig. 4. Helophilus hybridus Loew male.Plants providing nourishment: Ranunczslus acris - Rubusidaeus - Comarum palustre - Sanguisorba officinalis L. -Vaccinium myrtillus - Ilfyosotis sp. - Valeriana officinalis -Arnica montana - Taraxacum sp.Substrate during sunning : Rubus idaeus.Frequency: D e n m a r k: Rare (Lundbeck 1916). - TorpPedersen (1964) mentions 9 further specimens from Jutland(1963-64), and expects it to be found relatively frequently inthat part of Denmark. - G r e a t B r i t a i n : "Uncommon"(Coe 1953).In the Norwegian area investigated the species was found inmost places to occur frequently but in small numbers. An exceptionis the biotope at Oksnevad. In an open space, due to fellingin a spruce stand near a pool (0ksnevad tarn), the species occurredin large numbers and was far more abundant than theotherwise dominating H. pendulus. Most of the examples werecaptured at this biotope; the abundance of individuals here isalso much greater than can be inferred from the number collected,as relatively few insects were caught.Distinguishing characteristics: H. hybridus seems to be lessalert and less shy than the other Helophilus species. This wasespecially noticeable at 0ksnevad where, as mentioned, thespecies occurs abundantly together with H. pendulus. While H.