Dilophus crassicornis Skartveit, 2009: 31-34

Skartveit, John, 2021, A new fossil species of the genus Bibio, with an update on bibionid flies from Baltic and Rovno amber (Diptera, Bibionidae), Deutsche Entomologische Zeitschrift 68 (1), pp. 81-99 : 81

Dilophus crassicornis Skartveit, 2009: 31-34 Figs 9 , 29 , 30 , 31

Type material.

Holotype, male, MHNN 907. Paratypes: males, SDEI Dip-00835 - CCHH#932-4; SDEI Dip-00836 - CCHH#1629.1.

Non-type specimens previously examined.

Male, MHNN 1412, females: CCHH#932.2, CCHH#1121.

Additional material.

Female, CCHH # 1789-2; female, JS-Baltic-012, in piece of amber 15 ×8× 4 mm.

Redescription, female.

Total length 3.8-5.1 mm (N = 3).

Head (Fig. 29 ): Length 0.62-0.77 mm (N = 3), width 0.59-0.60 mm (N = 2), eye length 0.36-0.40 mm (N = 2), width 0.27 mm (N = 1). Flagellum 6-7-segmented, 0.32 mm long, 0.09 mm wide.

Thorax: Length 1.22-1.55 mm (N = 3), width 0.65 mm (N = 1, smallest specimen). Haltere light brown.

Wing: Length 3.44-3.75 mm (N = 2). Hyaline, slightly brownish, veins fine and brown. Pterostigma brown. Costa extends to half-way between apices of R4+5 and M1.

Legs: Brown, sparingly clad with fine, short, brown pile. Fore tibia (Fig. 30 ) slightly sinuate, mesally with three long, erect, sharp spines, apically with spine circlet of six long, diverging spines. Mid- and hind tibia apically with circlet of six spinose, brown setae. All tarsi slender. Measurements (all in mm, N = 3 unless otherwise stated) fore femur length 0.55-0.89, width 0.25 (N = 1), fore tibia length 0.64-0.95, width 0.09 (N = 1), fore first tarsomere length 0.40-0.44 (N = 2), mid femur length 0.70-0.92, mid tibia length 0.72-0.90, hind femur length 1.07-1.22, width 0.14 (N = 1), hind tibia length 1.14-1.22, width 0.13 (N = 1), hind first tarsomere length 0.50-0.62.

Abdomen: Length 2.7 mm (N = 1). Brown, conical. Terminalia in lateral view as in Fig. 31 .

Figures

Figure 9. Dilophus crassicornis, female. CCHH 1789 - 2. Photo: Christel and Hans-Werner Hoffeins.

Figure 29. Dilophus crassicornis, female, head and thorax. Scale bar: 1 mm.

Figure 30. Dilophus crassicornis, female, fore tibia. Scale bar: 0.1 mm.

Figure 31. Dilophus crassicornis ¸ female, terminalia, lateral view.