Cydistomyia fenestra 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 : 56-58

Cydistomyia fenestra Mackerras & Spratt , sp. nov.

( Fig. 40 )

Type material. Holotype female, north Qld , Kingfisher Lodge, Julatten, 400 m, Nov., 1998, C.J. Burwell ( QM T144398 ) . Paratype female, same data as holotype ( QM) .

Non-type material examined QLD, 1♀, Annan R. crossing, S of Helenvale , Jan., 1981, G. and A. Daniels ( GDCB) ; 1♂, Mt Finnigan summit, 1050m, Jan., 1991 ( QM) ; 2♀, Mt Misery , SW of Cooktown, Jan., 1994, G. and A. Daniels and R. Eastwood ( GDCB) ; 1♀, Windsor Tableland via Carbine, Jan., I. Fanning ( QM) ; 1♀, Mt Lewis Rd. , 29 km from highway, 1210m, Nov., 1998, C.J. Burwell ( QM) ; 3♀, 1 km N of Julatten, Nov. , 1998, C.J. Burwell ( QM) ; 2♀ Julat- ten, nr Mt Molloy , Oct., 1979, M.S. and B.J. Moulds ( GDCB) , Jan. , G & A. Daniels ( GDCB) ; Springbrook , Nov., 2000, G.R. Forbes ( GDCB) . NSW: 1♀ Brunswick Heads , Mar., 1991, R. Eastwood ( GDCB) .

Diagnosis. A medium to large sized 14–16 mm dark brown to blackish species representing a smaller coastal form near C. wentworthi and C. victoriensis , extending from Cape York in north Queensland to Brunswick Heads in northern New South Wales. Distinguished from all other species by combination of four morphological features; green eyes (relaxed), uniformly clouded greyish brown wings without suffusion along veins so much as in cells and with clear window in basal portion of cell R 1 extending apically to basal edge of stigma, more acute dorsal angle on basal plate with prominent tooth often directed anteriorly and all black hairs on both palpal segments. Further distinguished from C. wentworthi by much narrower frons, pyriform rather than quadrate callus although both with tapering extensions almost to ocellar tubercle, ash to slate grey rather than brown palps, scutum without traces of darker median and dorsocentral lines, wings very similar and both with clear window in basal portion of cell R 1 but with suffusion more within cells than along vein margins, with a coastal rather than montane habitus. Further distinguished from C. victoriensis by smaller size, callus not quadrate but with gently sloping shoulders; less concolourous appearance, with narrow pale apical margins and median triangles both covered with fine white hairs on abdominal tergites and from C. pruina by greater length of extension on callus, callus almost full width of frons at base, and absence of darker median and lateral vittae on scutum,

Female. Head. Eyes (relaxed) green, hairs not visible at 15x. Frons narrow, parallel to slightly divergent, index 6.6–6.8, with dark grey tomentum and short black hairs; vertex depressed, vertical triangle dark grey; ocellar tubercle inconspicuous in several specimen, well defined in most, raised, dark greyish black, one or more ocelli sometimes visible; callus raised, shiny, chocolate brown, not quadrate but with sloping shoulders (= pyriform) and tapering extension reaching almost to ocellar tubercle, almost full width of frons at base. Subcallus smooth, with grey tomentum in anterior portion, yellowish fawn in antennal pits, without hairs; parafacials and face with fawn grey tomentum with short black hairs; beard dull white. Antennal scape twice as long as wide with dark grey tomentum and long black hairs, without dorsal prolongation; pedicel similar, with moderate dorsal prolongation; basal plate brownish black with acute basal dorsal angle forming short sharp upward and often anteriorly directed tooth, ventral surface with gentle apical swelling; style black, slen- der, longer than basal plate. Palpi ash to slate grey with all black hairs on both palpal segments.

Thorax. Scutum and scutellum blackish, without traces of darker median and dorsocentral lines, scutum lighter brownish on lateral margins with short scanty appressed grey hairs. Pleura pale grey with grey hairs.

Legs. Femora and tarsi black with black hairs; tibiae brown with predominantly black hairs.

Wings. Almost uniformly clouded greyish brown in cells of basal two-thirds and with clear window in basal portion of cell R 1 extending apically to basal edge of stigma, with very little suffusion along veins and no discrete brown cloud in apical half. Costal cell entirely brown. (Wing markings more similar to wentworthi than to doddi , magnetica and alternata ).

Abdomen. Highly variable, general appearance from mixed brown and black to s late grey to black, with narrow pale margins to apices of some or all tergites and creamy white hairs over these, with pale median triangles covered with white hairs on tergites 2–5 or not at all; with smaller patch on tergite 1 or absent; with lateral patches of white hairs apically on tergites 1–4. Venter dark brown to almost black, often paler brown on 1 st sternite; with narrow apical margins and lateral patches both with fine white hairs on sternites 1–5.

Male. With paler abdomen, tergite 2 with black median vitta and large pale brown lateral areas, tergite 3 with broader dark median vitta and narrower brown lateral areas, remaining tergites black with narrow pale margins to apices of all tergites and creamy white hairs over these, with pale median triangles covered with white hairs on tergites 2–5 and smaller patch on 1 st tergite; with lateral patches of white hairs apically on tergites 1–4. Venter similar to female.

Distribution. NE and SE QLD, and NE NSW.

Etymology. The specific epithet refers to the Latin for window and derives from the characteristic clear window in the basal section of cell R 1 extending apically to the basal portion of the stigma in the wings of this species.

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.