Botanophila minuta Michelsen, 2009, sp. nov.

3. Botanophila minuta sp. nov.

Figs. 18–20.

Etymology. The specific epithet ‘minuta’ is a Latin adjective meaning ‘small’.

Description. Size. Very small, wing length 2.8–3.6mm (n=16).

Male. Greyish dusting on body relatively dense overall, even without a distinct dark subshine on abdomen. Frons at narrowest point subequal to or narrower than distance between inner margins of posterior ocelli; parafrontals at this point narrowly separated by frontal vitta. Parafacial at narrowest point not quite as wide as postpedicel. Gena in lateral aspect also somewhat narrower than postpedicel; genal setae in two rows. Arista slightly longer than antenna measured from base of scape to tip of postpedicel; aristomere 3 thickened on basal third. Palp shorter than fore tarsomere 1; prementum longer than fore tarsomere 1, covered in thin dusting. Thorax covered in rather dense greyish dusting, on mesonotum with three dark brown stripes apparent in oblique posterior aspects. Presutural acrostichal rows in front farther apart than their distance to adjacent dorsocentral rows; middle pair of acrostichals moderately enlarged; several setulae present between rows. Notopleuron without accessory setulae. Proepimerals 3–5 setae and setulae. Wing base and calyptrae dark brown tinged, knob of halter ochreous yellow. Abdomen covered in greyish dusting; in posterior aspects revealing a broad blackish mid-dorsal stripe and anterior bands on tergites II–V. Terminalia (Figs. 18, 19) very similar to those of B. helviana, see under that species for differences.

Female. Parafacial at narrowest point distinctly narrower than width of postpedicel. Gena in lateral aspect somewhat narrower than postpedicel; genal setae in two close-set, irregular rows. Arista slightly longer than antenna measured from base of scape to tip of postpedicel; aristomere 3 thickened on basal third. Palp shorter than fore tarsomere 1; prementum longer than fore tarsomere 1, with a dark subshine through thin dusting. Thorax covered in grey dusting; three narrow brown mesonotal stripes visible in posterior aspects. Presutural acrostichal rows in front farther apart than their distance to adjacent dorsocentral rows; middle pair of acrostichals moderately enlarged; several setulae present between rows. Notopleuron without accessory setulae. Proepimerals 2–4 setae and setulae. Wing bases and calyptrae brownish tinged; knob of halter ochreous yellow. Abdomen with thin but distinct greyish dusting allowing a blackish subshine. Oviscapt (Fig. 20): Almost as in B. helviana (Fig. 14) except for narrower sternite VI.

Biology. In south-central Norway an early-season species of the subarctic Betula -zone occurring together with the previous species, B. kitadakeana.

Material examined. Type material: NORWAY [ZMUC]: Sør-Trøndelag (inner): Kongsvoll (62.18N / 09.36E), 900–1100m, 7 males [including holotype] 6 females, 12-20.vi.1985 (V. Michelsen). SWEDEN [MZLU]: Torne Lappmark: Abisko (68.21N / 18.46E), 400m, 1 male 1.vii.1947 (O. Ringdahl), 1 male 7.vii.1948 (H.C. Huckett), 1 male 16.vii.1951 (J.R. Vockeroth).

Other material (not examined). SWEDEN [Coll. D.M. Ackland]: Torne Lappmark: Abisko, Abiskojokk–Ridonjira junction, 390m, 1 male 4.viii.2001 (B. Merz).

Distribution. So far known only by the type material from south-central Norway and northern Sweden.