Cydistomyia pruina Mackerras & Spratt, 2008

Mackerras, I. M., Spratt, D. M. & Yeates, D. K., 2008, Revision of the horse fly genera Lissimas and Cydistomyia (Diptera: Tabanidae: Diachlorini) of Australia, Zootaxa 1886 (1), pp. 1-80 : 59-60

Cydistomyia pruina Mackerras & Spratt , sp. nov.

( Fig. 41 )

Type material. Holotype female, NSW, Alpine Creek , Kiandra, Jan. 1935, T.G. Campbell ( ANIC) . Paratype females (6), same data as for holotype ( ANIC) .

Non-type material examined. ACT: 1♀ Bendora , 9.ii.1948 , 1♀ 13.ii.1950, S.J. Paramonov ( ANIC) ,. NSW:): 1♀ Mt Gingera ,, 17.ii.1965, A.L. Dyce and M.D. Murray ( ANIC) ; 1♀ Wee Jasper , 914 m, 29.i.1933, M. Fuller ( ANIC) ; 2♀ Alpine Ck , Kiandra, 30.i.1964, T.G. Campbell ( ANIC) , 1♀ 1.i.1963, J. Bancroft and I.M. Mackerras ( ANIC) , 1♀ 16.i.1935, S.J. Paramonov ( ANIC) ; 1♀ 13 km SE Talbingo , 30.i.1964, T.G. Campbell ( ANIC) ; 2♀ Brindabella to Rules Point, 30.i.1964, G. Wellings ( ANIC) ; 3♀ 5 km NW of Rules Point , 30.i.1964, T.G. Campbell ( ANIC) ; 1♀ Tinpot Clearing , Rules Point, 18.ii.1965, A.L. Dyce and M.D. Murray ( ANIC) ; ♀ Lake Blowering , 14.ii.1977, H. McKenzie ( AM) ; 2♀ Snowy Plains , 1219 m, biting, 11.ii.1978 , 2♀ 17-18.ii.1975, D.M. Spratt ( ANIC) , 1♀ 28.ii.1980, P. Haycock ( ANIC) ; 1♀ Thredbo R, 25.ii.1990, A.L. Dyce ( ANIC) ; 1♀ Mt Kosciuszko , 1219 m, 29.i.1933 , 1♀ 27.i.1963, I.M. Mackerras ( ANIC) , 2♀ 1524 m, 11.ii.1924, A.J. Nicholson ( ANIC) ; 2♀ Yellow Bog Creek , Kosciuszko Nat. Pk., 17.i.1978, G. Daniels ( GDCB) . VIC: 1♀ Bonang , SW of Delegate, i.1938, F.E. Wilson ( ANIC) ; 1♀ Bogong , SE of Myrtleford, 23.i.1965, N. Dobrotworsky ( ANIC) .

Diagnosis. A medium-sized slatey grey species with conspicuous pale apical bands bearing line of creamy white hairs on abdominal tergites, pale grey wings without darkened costal cell and without brown suffusion along veins, and narrow basal plate with small gentle dorsal angle sometimes bearing small upwardly pointing tooth on antennal flagellum. This species represents the southern highland member of the C. doddi - C. wentworthi series and clearly links it with the large southern C. victoriensis . It is distinguished from C. wentworthi by clear wings, ill-defined ocellar tubercle, wider frons with differently shaped callus and extension which does not generally reach middle of frons, weak dorsal angle on basal plate, uniformly brown legs and characteristic abdominal markings. To be distinguished from C. victoriensis by smaller size, paler slate-grey colouration, clear wings, inconspicuous ocellar tubercle, generally wider frons with differently shaped callus, paler palps, paler antennal scape and pedicel, narrower basal plate with less pronounced dorsal angle, and characteristic abdominal markings. Length 13–17 mm.

Female. Head. Eyes (relaxed) black, with short fine sparse hairs just visible at 15X magnification. Frons medium, parallel to slightly divergent, index 3.5–4.5, with grey to greyish fawn tomentum and longish black hairs; vertex depressed; vertical triangle well defined, lighter grey than general tomentum, with short black hairs; ocellar tubercle poorly defined, when present somewhat elongate, depressed, brown; ocelli not visible; callus pyriform, raised, shiny, dark brown, about two-thirds width of frons at base, with tapering extension generally not reaching to middle of frons. Subcallus with fawn grey tomentum, no hairs; parafacials and face with similar but paler fawn tomentum, with numerous black hairs mixed with dull yellowish ones; beard dull greyish cream, with few black hairs. Antennal scape and pedicel brownish fawn, with black hairs; basal plate dark brownish black, narrow, with gentle dorsal angle, sometimes with short upward pointing dorsal tooth; style slightly darker. Palpi brownish fawn, narrow, with short mixed black and white hairs on segment 1, predominantly all black on segment 2.

Thorax. Scutum and scutellum dark grey, former with clear indications of darker median and lateral vittae, lighter grey lateral margins; hairs mixed black, grey and greyish white, not appressed. Pleura brownish grey, hairs greyish white anteriorly, mixed with black hairs on mesopleural convexity, with prominent tuft of long creamy white hairs on hypopleural convexity.

Legs. Brown, darkening on tarsi; hairs on femora mixed greyish white and black, predominantly black elsewhere.

Wings. Greyish, costal cell not darkened; veins not suffused with brown along margins.

Abdomen. Slate-grey, with conspicuous pale apical bands bearing line of creamy to creamy white hairs on all tergites. Band usually expanding slightly to form small median triangles with creamy white hairs on tergites 2–5 and similar lateral triangles on tergites 2–4, elsewhere hairs black. Venter paler slate-grey, with similar pale apical bands on all sternites but not bearing creamy white hairs, hairs mixed black and greyish white overall.

Distribution. Inland high country ACT, NSW and VIC.

Etymology. The specific epithet derives from the Latin for hoarfrost and refers to the characteristic abdominal pattern of this species which is suggestive of a coating of hoarfrost similar to that which occurs commonly at Alpine Ck, Kiandra.

Figures

FIGURES 40–42. 40. Cydistomyia fenestra Mackerras & Spratt, sp. nov. frons, antenna, palp, female terminalia, sternite 8, spermathecal bulb. 41. Cydistomyia pruina Mackerras & Spratt, sp. nov. frons, antenna, palp, female terminalia, sternite 8, spermathecal bulb. 42. Cydistomyia infirmus Mackerras & Spratt, sp. nov. frons, antenna, palp.