Bibio nigriventris Haliday, 1833

Skartveit, John, 2010, The larvae of European Bibioninae (Diptera, Bibionidae), Journal of Natural History 36 (4), pp. 449-485 : 467-469

Bibio nigriventris Haliday, 1833 (®gures 47±53)

Larva described by Morris (1921). White, rather shiny, body processes short. Total length full-grown 11.0± 12.8 mm (n = 10).

Head. Yellowish red. Head capsule width seventh instar 0.89±0.92 mm (n = 10). Labrum (®gure 47) with one pair of short setae on transverse carina. Mandible (®gure 48) with three teeth. Maxilla (®gure 49) mesally with three prominent teeth, one tooth between mesal teeth and comb, maxillary comb consisting of ®ve to six indistinct teeth. Inside of maxilla with 13±17 round`holes’, maxillary palp with a series of ®ve spines on membraneous area. Prementum (®gure 49) with 8±10 sensillae. Stemmata absent. Antenna diameter ca 40 m m with ®ve to six sensillae.

Body. Processes rather short. Dorsal processes arranged in three pairs. Postspiracular processes approximately as long as three times spiracle diameter, placed approximately 3.5 spiracle diameters posterior to spiracle. Cuticle: scales wihout spines, roundish oval, with a regular outline, approximately 15 ±25 m m in diameter. Prothorax (®gure 50) scales rather closely packed, those on other segments (®gures 51±53) separated by approximately one scale diameter from each other. Except for the segment borders, the cuticle structure is rather homogenous all over the body. Spiracles comparatively small and not at all protruding from the body surface.

Distribution. Common over most of Europe but uncommon above the timberline.

Ecology. Rather eurytopical but most abundant in deciduous woodlands. Also occurs in coniferous forests. Larvae feed on leaf litter. Full-grown larvae in March to May.

Material. Norway, RY: Finnùy , Sevheim, birch forest, 30 December 1993 10 larvae , 20 April 1994 3 larvae , 23 April 1994 2 larvae, 26 April 1994 4 larvae, 16 February 1995 112 larvae, 15 April 1995 68 larvae, J. Skartveit leg. ( ZMUB) . Norway, HOY: Bergen , Flùyen, beech forest 14 April 1994 3 larvae, J. Skartveit leg. ( ZMUB) .