Cairnsimyia

Mcalpine, David K., 2013, Supplementary descriptions of Australian Rhinotorini (Diptera: Heteromyzidae), Zootaxa 3680 (1), pp. 130-138 : 132

Key to species of Cairnsimyia

1. Ocellar and humeral bristles minute or absent; anterior marginal zone of postfrons precipitous; prelabrum with median process or prominence; SE New Guinea, N Queensland.............................................. C. aroana McAlpine

- Ocellar and humeral bristles large; anterior marginal zone of postfrons not steeply sloped; prelabrum without process or distinct prominence..................................................................................... 2

2. Fronto-orbital bristles two; all femora with thickened spine-like ventral bristles; male: pregonite large with one or two terminal spines.............................................................................................. 3

- Only one fronto-orbital bristle present; femora without spinescent ventral bristles; male: pregonite undeveloped.......... 5

3. Second costal cell with two or three brown spots; male: surstylus somewhat narrowed basally, with produced anterodistal angle not recurved; S Queensland, New South Wales, Victoria, Tasmania, South Australia................ C. robusta (Walker)

- Second costal cell without spots; male: surstylus not as above.................................................. 4

4. Sternopleuron (katepisternum) with large bare, shining posterior zone; all tibiae with brown preapical zone and substantial yellow apical zone; tarsal segment 5 largely tawny; male: surstylus very attenuated basally, with produced anterodistal angle recurved; S Queensland, New South Wales, Tasmania, Western Australia........................ C. excavata McAlpine

- Sternopleuron almost entirely dull, pruinescent; all tibiae with substantial brown apical zone; tarsal segment 5 black (brown in faded specimens); male: surstylus not so much attenuated basally, broadened and elbowed before middle, with slender distal part directed anteriorly; New South Wales............................................... C. sydneiensis McAlpine

5. Prescutellar acrostichal bristle absent..................................................................... 6

- Prescutellar acrostichal bristle present..................................................................... 8

6. Antennal segment 3 not longer than deep; fore tarsus entirely orange-tawny; mid femur with group of moderately stout black anterior bristles near and beyond mid-length; New South Wales.................................. C. englishae n. sp.

- Antennal segment 3 horizontally ovoid; fore tarsus orange-tawny basally, with segments 2 to 5 largely dark brown; mid femur with only long, fine undifferentiated setulae on anterior surface................................................ 7

7. Arista somewhat thickened, pale, with dense white pubescence; W and E New Guinea............. C. inscripta (Walker)

- Arista slender, brown, with very inconspicuous pubescence; E New Guinea...................... C. crosskeyi McAlpine

8. Cheek region with many dark brown spots of various sizes, each at base of a bristle or setula; postvertical bristle usually c. as large as fronto-orbital bristle; male: surstylus broadly obliquely oval; Queensland, New South Wales. C. verticalis McAlpine

- Cheek region with few or no spots; postvertical bristle very small or absent; male: surstylus not as above................ 9

9. Mesoscutum pale greyish, with isolated reddish brown marks; sternopleuron dark reddish brown, contrasting with very palepruinescent mesopleuron; male: surstylus narrowly elongate, not broadened distally ( Fig. 8 ); N Queensland..................................................................................................... C. collessi n. sp.

- Mesoscutum predominantly reddish brown, with pale grey to yellowish markings; sternopleuron not conspicuously dark; male: surstylus not as above................................................................................ 10

10. Cheek region with reddish brown spot immediately behind vibrissa; postfrons with very broad pale greyish- to yellowish-pruinescent anterolateral zone on each side; male: surstylus broadly spatulate, with rounded distal margin; S Queensland, New South Wales, Victoria.................................................................. C. uniseta McAlpine

- Cheek region without such spot; postfrons anterolaterally with only narrow, marginal pale-pruinescent zone; male: surstylus very broadly subtriangular, with broad, slightly sinuate distal margin; Queensland, N New South Wales..................................................................................................... C. cavifrons Malloch

Figures

FIGURE 6 – 8. Cairnsimyia collessi, male. 6, whole insect. 7, head. 8, genital segment, posterior view (scale = 0.2 mm).