McAlpine: Australian Helosciomyzidae 
67 
zone, extending near the base, contrasts particularly with the 
condition in H. australica, less so with that in H. macalpinei. 
Separation of the females of H. obliqua from those of related 
species is often a matter of uncertainty. 
The specific epithet is a Latin adjective meaning oblique, 
in reference to the outline of the surstylus. 
Helosciomyza driesseni n.sp. 
Figs 25, 27 
Type material. Holotype Tasmania: Flood Creek, 
near Lake Saint Clair, 42.102°S 146.113°E, button grass 
moorland, 16-17.ii.2004, M.M.D. (AM K264371). Double- 
mounted on micro-pin through polyporus after preservation 
in ethanol, postabdomen in micro-vial on pin. Paratypes. 
Tasmania: 2<$S, 2$$, same data as holotype (AM, ANIC); 
2?$, Rufus Canal Road East, 42.10°S 146.75-146.86°E, 
Feb. 2004, M.M.D. (AM); 1 $, “Bedlam”, 42.73°S 146.10°E, 
Feb. 2004, M.M.D. (AM); 2SS, Dove Lake, Cradle 
Mountain National Park, Dec. 2003, S.A.M. (AM, TDPI). 
Description (male, female). Resembling other species of the 
juscinevris group in most characters; agreeing approximately 
with description of H. bickeli except as indicated below, but 
because most specimens have been immersed in ethanol 
for five years before drying and mounting, some details of 
coloration are imperfectly preserved. 
Coloration. Occipital region with broad dark cuticular 
mark of characteristic shape (Fig. 27). Antennal segment 
3 with large brown zone between aristal insertion and 
apex, tawny-orange basally and ventrally. Palpus tawny- 
yellow, sometimes faintly browned apically. Fore femur 
tawny-orange, on anterior surface with broad brown zone 
extending from near apex almost to base, on posterior 
surface with posterodorsal dark grey-pruinescent diffuse 
zone of variable length, usually becoming narrower and more 
distally restricted or fading distally, but without separate 
dark brownish subapical mark centred on posterior surface 
as in H. macalpinei. 
Head. Cheek c. 0.39 as high as eye. 
Thorax. Pteropleuron and hypopleuron without setulae; 
proepimeral bristle minute or absent. Fore tarsal segment 4 
often shorter and broader than in corresponding sex of H. 
macalpinei. 
Abdomen. Sternite 1 vestigial, without setulae. Male 
postabdomen: surstylus (Fig. 25) relatively slender, curved, 
not distally broadened, with large, setulose posterobasal 
tubercle and moderately developed setulae posteriorly and 
on medial surface. 
Dimensions (most specimens not accurately measurable). 
Total length, 5.2 mm, $ 5.7 mm; length of thorax, $ 2.6 
mm, $ 2.6 mm; length of wing, 6.2 mm, $ 6.4 mm. 
Distribution. Tasmania: northern to south-central highlands. 
Notes 
Helosciomyza driesseni, together with H. macalpinei and 
H. obliqua, belongs with those species of the fuscinevris 
group having no pteropleural setulae, antenna 3 strongly 
infuscated in part, and the fore femur with brown zone on 
anterior surface extending near base. Helosciomyza driesseni 
differs from related species in having a broad dark mark of 
characteristic shape just above the occipital foramen (Fig. 
27). This mark is due to dark cuticular pigment and, though 
partly obscured by pale pruinescence, is demonstrably 
present in nine of the ten available specimens of H. driesseni. 
Other species of the fuscinevris group have at most a 
more restricted dark zone, more or less surrounding the 
supracervical setulae. In the male of H. driesseni the form 
of the surstylus is distinct from that of H. obliqua and H. 
macalpinei (compare Fig. 25 with Figs 24,26). The two latter 
species are only known from mainland Australia, whereas H. 
driesseni is from the Tasmanian highlands, but it is possible 
that the distributions are incompletely known. 
Michael Driessen indicates that his material of H. 
driesseni was collected by sweeping vegetation on button 
grass moorland. This is a low vegetation community 
dominated by the sedge Gymnoschoenus sphaerocephalus, 
and is characteristic of certain parts of the Tasmanian 
highlands. 
The specific epithet refers to Michael M. Driessen, who 
collected type material. 
Helosciomyza macalpinei Steyskal 
Figs 6, 7, 26 
Helosciomyza macalpinei Steyskal, in Steyskal & Knutson, 
1979: 737-738, fig. 23, ?fig. 24; Barnes, 1981: 57, figs 
15, 16. 
Type material (re-examined D.K.M.). Holotype S. New 
South Wales: Clyde Mountain, near Braidwood, 2400 ft. [c. 
730 m], 25.ii.1961, D.K.M. (AM K264247). Allotype 
Same data as holotype (AM). Paratypes. ?>$$, 2$ same 
data as holotype. 
The above specimens have been correctly determined 
and listed by Steyskal (1979: 738). Otherwise the published 
list is unreliable, as some given localities do not apply to H. 
macalpinei (e.g., Careel Bay and Otford), and specimens 
from Mount Wilson, appropriately labelled by Steyskal as 
paratypes of H. macalpinei, are not mentioned. 
Other material (all checked by D.K.M.; localities only 
given). New South Wales: Wright’s Lookout, New England 
National Park (AM); Mount Wilson (AM); below Govett’s 
Leap, near Blackheath (AM); Katoomba (AM); Wentworth 
Falls (AM); Deep Creek, near Narrabeen (ANIC); Rutherford 
Creek, Brown Mountain, Nimmitabel district (ANIC). 
Distribution. New South Wales: mainly cool, mountainous 
localities in north and south; single authentic record for 
coastal lowlands (Deep Creek). 
Figure 27. Helosciomyza driesseni, upper part of occiput, showing 
characteristic dark mark, most setulae omitted. 
