Bandella albitarsis, Bickel, 2002

Bickel, Daniel J., 2002, Bandella, A New Hilarine Fly Genus from Australia (Diptera: Empididae), Records of the Australian Museum 54, pp. 313-324 : 324

Bandella albitarsis n.sp.

Figs. 2f

Type material. HOLOTYPE, 3, New South Wales : New England NP, 13.x.1962, D.H. Colless ( ANIC).

Additional material. New South Wales: ♀, Dorrigo NP, 15.x.1966 ( ANIC); 3, Blue Mountains , Blackheath, x.1930 ( MVM) .

Description (male): length: 8.0; wing: 7.5×2.2. Head: postcranium shining black, with silvery pruinose band around outer rim except near vertex; frons shining black with no pruinosity; ventral postcranium with scattered pale setae; postorbitals entirely white, within silvery pruinose band; face covered with golden pruinosity; labrum and labellum yellow; scape and pedicel yellow-brown; first flagellomere dark brown.

Thorax: cuticle glabrous with little pruinosity; pleura and mesonotum mostly red-brown, but mesonotum with black areas laterally, and with pale yellow humeral, pronotal and notopleural areas ( Fig. 2f); scutellum orange; postnotum mostly dark brown; distinct patches of orientated silvery pruinosity visible in posterolateral view on following thoracic areas: middle of postnotum, anatergite, meron, and area of anepisternum just anteriad of wind base; posterior slope of mesonotum with scattered short setulae.

Legs: coxae, trochanters and all femora reddish yellow except trochanters with black apices; leg vestiture mostly yellowish; coxae with only short vestiture, no strong setae; all tarsi with strong black claws and large yellowish pulvilli; TI and It 1 dark brown to black with reddish vestiture, in sharp contrast to the ivory white It 2–5; TI and each tarsomere It 1–3 with some short av-pv setae; TI without distinct anteroapical comb; It 1 slightly swollen (MSSC); TII and tarsus II red yellow; TII with ad row of 8–10 short yellowish setae along length; IIt 1–3 each with some short av-pv setae; IIt 3 and IIt 4 with dense pale ventral pile; TIII and IIIt 1 red yellow, and IIIt 2–5 distinctly pale yellow; FIII not clavate; IIIt with short vestiture.

Abdomen entirely red-brown, with some brownish infuscation distally; cuticle glabrous, without pruinosity; tergum 7 slightly excavated distally; hypopygium (not figured) almost entirely yellow.

Female similar to male except as noted: post-cranium also with silvery pruinose band around outer rim; thorax of similar colour and with similar pruinose patches; TI yellowish basally but dark brown in distal half; It 1 black but not swollen; tarsomeres t 2–5,on all three legs distinctly white; leg vestiture somewhat weaker than on male.

Remarks. Bandella albitarsis is known from the Dorrigo Escarpment in northeastern New South Wales, and the Blue Mountains west of Sydney, both at elevations above 750 m. All specimens were collected in October.

This species has several diagnostic characters, developed in both sexes: (a) Bright silvery pruinose areas are distinctly visible in oblique view on the following areas: a band around the rim of the postcranium, middle of the postnotum, the anatergite, most of the meron, and the area of anepisternum just anteriad of wing base. These silvery patches may facilitate mating in flight, especially since incident light would make them appear to “flash” while turning. (b) Leg I has tarsomeres 2–5 ivory white in both sexes. In males, tarsi II and III are mostly yellow, whereas in females, all tarsomeres 2–5 on legs III and III are distinctly white. The white distal tarsomeres are more strongly developed on females than males, and should be regarded as a female secondary sexual character (FSSC) that is only weakly developed in males.

The male from New England National Park had Leptospermum pollen on its proboscis, and probably was nectar feeding.

ACKNOWLEDGMENTS. I thank the following institutions and their curators for loan of specimens:AMS, Australian Museum, Sydney, M. Moulds; ANIC, Australian National Insect Collection, CSIRO, Canberra, P. Cranston; CNC, Canadian National Collection, Ottawa, J. Cumming; MVM, Museum of Victoria, Melbourne, K. Walker. B. Sinclair provided both sound advice and specimens (deposited CNC) for this project. S. Bullock drew the genitalic figures. The habitus of Bandella duvalli was drawn by H. Finlay. This research was supported by Australian Research Council grant A19232651, for study of the systematics of Australian Empidinae . Additional support was provided by S. Duvall through the Australian Museum “Immortals” programme.