Review of the Australian Genus Pentachaeta (Diptera: Heleomyzidae), with Descriptions of Nine New Species
McAlpine, David K.
Records of the Australian Museum
2014
2014-10-22
66
5
247
264
McAlpine, 2014
McAlpine
2014
[935,1204,151,178]
Insecta
Heleomyzidae
Pentachaeta
Animalia
Diptera
10
256
Arthropoda
species
bassiana
sp. nov.
Figs 23–25
Type material. Holotype ♂. Tasmania: Marakoopa Caves, near Mole Creek, c. 41°35'S 146°17'E, 10.i.1960, D.K.M.( AM K310594). Gluedto card point, surstyli exposed, postabdomen not dissected. Paratypes. Tasmania: 2♂♂, same data as holotype ( AM); 2♂♂, Hellyer Gorge, upper (eastern) Arthur River district, Feb. 1967, E.F.R. ( ANIC); 2♂♂, 2 miles[c. 3 km] E of Tonganah, near Scottsdale, Jan. 1960, D.K.M.( AM); 1♂, near Russell Falls, Mount Field National Park, Jan. 1960, D.K.M.( AM). Other material examined. Males. Victoria: Belgrave, near Melbourne ( AM, MV).
Description (male, females not yet identifiable) Resembling P. edwardsiand related species without sexual dimorphism of tibiae; agreeing with description of that species, except as indicated below. Colorationgenerally as for genus; details as given for P. edwardsi. Abdomen. Surstylus ( Fig. 23) with basal foot extended narrowly on margin of epandrium posteriorly, much broadened near and beyond mid-length but contracted to short, narrow apical section, on most of outer surface densely microtrichose but with few minute macrotrichia, apically with several larger macrotrichia on inner surface, basally on inner surface with compact sclerotized tubercle bearing few short macrotrichia; subepandrial process ( Fig. 25) somewhat resembling that of P. edwardsi; gonostylus more nearly resembling that of P. bickeli, with typically three long macrotrichia and scabrous zone which varies from slightly convex to slightly concave; aedeagus without invaginated teeth; cercus ( Fig. 24) somewhat elongate, but expanded anteriorly to mid-length, with the pair of anterior lobes strongly diverging, each apically compressed, rounded and slightly twisted, outer surface with large macrotrichia posteriorly, minute ones anteriorly, and with general covering of microtrichia, but without distinctly angular outline and tubercle. Figures 23–25. Pentachaeta bassiana(23)pair of surstyli, posteroventral view (Marakoopa Caves); structure on inner surface of basal half seen through transparency; scale = 0.1 mm; (24)pair of cerci, oblique ventral view (Belgrave); setulae shown only on left cercus; scale = 0.2 mm; (25)left gonostylus, subepandrial process and associated parts (Marakoopa Caves); scale 0.1 mm. Dimensions. Total length 3.3–3.6 mm; length of thorax, 1.5–1.8 mm; length of wing, 4.1–4.6 mm.
Distribution. Tasmania: probably widely distributed. Victoria: vicinity of Melbourne. Map references 4L, 4N, 5N, 5O ( Fig. 4). Notes Pentachaeta bassianabelongs among those species without sexual dimorphism of the tibiae and with entirely dark male fore tarsus. Among these, the male has the surstylus with quite distinctive shape ( Fig. 23), and the cercus is also characteristic. The specimen examined from Belgrave, Victoria, differs from the Tasmanian specimens (Marakoopa Caves and Hellyer Gorge) in having the surstylus slightly broader, the anterior lobe of the cercus shorter, and the setulae on the subepandrial process and gonostylus more numerous. These differences are slight, and study of more material is needed before significant divergence between the Victorian and Tasmanian populations can be accepted. The specific epithet has the form of a Latin adjective and refers to the occurrence of the species on both sides of the Bass Strait.
1960-01-10
AM
David K. McAlpine & Glued
-41.583332
Mole Creek
1155
146.28334
Marakoopa Caves
10
256
K310594
1
1
Tasmania
holotype
1960-01-10
AM
David K. McAlpine & Glued
-41.583332
Mole Creek
1155
146.28334
Marakoopa Caves
10
256
2
2
Tasmania
paratype
1967-02
ANIC
Arthur River district
Hellyer Gorge
10
256
2
2
Tasmania
paratype
1960-01
AM
David K. McAlpine
Scottsdale
10
256
2
2
Tasmania
paratype
1960-01
AM
David K. McAlpine
Mount Field National Park
Russell Falls
10
256
1
1
Tasmania
paratype