Cydistomyia palmensis (Ferguson & Hill)

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 : 21-23

Cydistomyia palmensis (Ferguson & Hill)

( Fig. 17 )

* Tabanus palmensis Ferguson & Hill, 1922: 256 ; Hardy 1939: 42, 1944: 83. Type female, N Qld, Palm Island (ANIC) Cydistomyia palmensis ; Mackerras 1959: 166; Daniels, 1989: 287; Bickel & Elliot, 1998 -2005: 4..

Tabanus nigropictus ; Hardy, 1939: 42, nec Macquart, 1855: 44 (erroneously as syn. of palmensis Ferguson & Hill ). Other material examined. 97♀, 3 ♂.

Diagnosis. A medium-sized rather slender species with dark dorsum contrasting with much paler colour of pleura and venter, with brown antennae and legs, and faintly brown wings. Readily distinguished from similar species by almost shiny chocolate brown colouration, characteristically dark brown median lunulate markings contrasting with pale grey lateral areas on sternites, and conspicuous dark brown stigma. In addition, it is distinguished from torresi as noted under that species; from C. pseudoardens by more conspicuous pale median abdominal triangles, wings generally more prominently suffused with brown, and less robust basal plate with small dorsal sub-basal tooth on antennal flagellum; from C. fergusoni by dull scutum with little indication of vittae, conspicuous dark brown stigma, narrower frons with differently shaped callus, and narrower basal plate; and from C. bancroftae by conspicuous pale median abdominal triangles, dark brown stigma, narrow frons with conspicuous callus, and more typical rather than undersized antennae. Length 10–14 mm, usually 13–14 mm.

Female. Head. Eyes (relaxed) reddish green, bare, (with sparse fine hairs just visible at 35X magnification). Frons narrow, margins parallel or slightly convergent, index 5.4–5.7, covered with fawn-brown tomentum, paler along eye margins, with short dark hairs on darker part; vertex slightly hollow; vertical triangle greyish brown, with relatively dense short black hairs; ocellar tubercle irregular, oval, rather flat, surrounded by zone where tomentum is thin and frons slightly shiny; callus dark brown, shiny, slightly bulging, practically full width of frons at base, narrowing to tapered extension which reaches a little above middle of frons. Subcallus with greyish cream tomentum, brownish yellow above antennae, without hairs. Parafacials and face with greyish white tomentum and rather fine white hairs; beard white. Antennae bright brown, with style darker; scape about one and a half times as long as wide, with small dorsal prolongation and short black hairs; pedicel cup-shaped, with small dorsal prolongation and short black hairs; flagellum rather elongate, basal plate about one and a half times as long as style, with small but sharp dorsal tooth close to base. Palpi brownish grey, with short brown hairs.

Thorax. Scutum and scutellum dull brown, with faintly indicated dorsocentral lines in front of suture and more greyish lateral margins, hairs mixed black and creamy white, latter diffuse, not giving effect of pale posterior margin to thorax. Pleura pale grey, with white hairs.

Legs. Brown; fore femora and tibiae darker than others; all tarsi darkening to blackish brown; hairs preponderantly white on femora, black on remaining segments.

Wings. Lightly but distinctly and uniformly suffused with brown; veins chocolate brown; stigma shiny, chocolate brown, conspicuous.

Abdomen. Chocolate brown, darker than scutum, darker apically than on 1st and 2nd tergites; all tergites with narrow inconspicuous paler apical margins, tergites 2–5 with well-defined median white haired apical triangles; elsewhere hairs creamy white and conspicuous. Venter characteristic, predominantly grey on 1 st sternite and lateral areas of sternites 2–6, dark brown colour reduced to wide lunulate median markings on sternites 2–6, hairs black on darker parts, creamy white on paler areas, entirely black on 6 th and 7 th sternites.

Male. Similar to female but more hairy, with thorax and abdomen more conspicuously marked and wings with less suffusion. Eyes with short fine hairs visible at X15 magnification, upper facets enlarged, reddish brown, contrasting with small lower and posterior dark ones. Ocellar tubercle raised slightly above eyes, ocelli not observed. Palpi fawn, second segment with mixed dark brown and white hairs. Thorax with more clearly defined dorsocentral and lateral vittae, with pale grey posterior margins on scutum and scutellum. Abdomen with broader pale apical margins on tergites, widening to form conspicuous median triangles on tergites 2–5.

Distribution. From Cape York N QLD S to Townsville, with a single southern record near Ipswich. QLD: Iron Range, Dec., S.J. Johnston; West Claudie R, Iron Range, Dec., G.B. Monteith and D. Cook; Shipton’s Flat, 36 km S. Cooktown, Nov., D.K. Yeates; Bloomfield Rd via Helenvale, Oct., G.B. Monteith; Mt Finnigan summit, Nov., C.J. Burwell, Dec., G.B. Monteith; 1.5 km NW Cape Tribulation, Nov., G.B. Monteith; 3–5 km W Cape Tribulation, Sept., Dec., G.B. Monteith; Cape Tribulation, Dec., G. Daniels and M.A. Schneider, G.B. Monteith; Cooper Creek, 29 km N Daintree River, Nov., T. Weir; 2 km SSE Mt Spurgeon, Nov., C.J. Burwell; 7.5 km and 4 km NW Kuranda, Jan., Feb., Storey and Halfpapp; Cairns, Edge Hill, Dec., C.F. Ashby; Cairns, F.H. Taylor; Meringa, Nov., G.M. Goldfinch; Kauri Ck, Tinaroo, Dec., D. Gibson; Upper Mulgrave R., Gordonvale, Apr., S.R. Curtis; Mt Edith, 1036 m, Mar., I.F.B. Common and M.S. Upton; Atherton, Jan., G. Ettershank; Station Creek, Nov., C.J. Burwell; Mt Lewis Rd 29 km from highway, Nov., C.J. Burwell; Bellenden Ker Ra, Oct.; The Boulders via Babinda, Dec., B. Cantrell; Henrietta Ck, Palmerston Nat. Pk, Apr., S.R. Curtis, Sept., H.A. Standfast and A.L. Dyce; Bartle Frere, Nov., D. Elliott; Ninos Ck, Innisfail, Mar., H.A. Standfast; Gooligan Ck, nr Innisfail, Apr., R. Domrow; Boulder Creek via Tully, Oct., G.B. Monteith; 40 km W of Tully, Mar., I.F.B. Common and M.S. Upton; Mission Beach, Nov., G.B. Monteith; Gayundah Ck, Hinchinbrook Is., Nov., G.B. Monteith and D. Cook; Palm Is., Nov.-Dec., A. Breinl, Dec.-Jan., I.M. and M.J. Macker- ras; Mt Spec, 305 m, Jan., P. Ferrar, Apr., K.L.S. Harley; Little Crystal Ck, Mt Spec, biting, Nov., Dec.; Mt. Halifax, 45 km W Townsville, Dec., Jan., A. Graham; Kholo, nr Ipswich, Dec., M. Colbo.

The last very southern record (Kholo, nr Ipswich)is surprising but the specimen bears all the characteristic morphological features of the species.

Figures

FIGURES 16–18. 16. Cydistomyia danielsorum Mackerras & Spratt, sp. nov. frons, palp, antenna, female terminalia, sternite 8, spermathecal bulb. 17. Cydistomyia palmensis (Ferguson & Hill) frons, palp, antenna, female terminalia, sternite 8, spermathecal bulb. 18. Cydistomyia pseudoardens (Taylor) frons, palp, antenna, female terminalia, sternite 8, spermathecal bulb.