Apetaenus (Macrocanace) australis Hutton 1902

Apetaenus (Macrocanace) australis (Hutton, 1902)

(figs. 1–2, 5, 7–8)

Ochtiphila australis Hutton, 1902: 174 [Campbell Island; HT ɗ, NZAC (originally in the Cawthron Institute collection). However, the holotype does not appear in the list of the “Primary type specimens in the New Zealand Arthropod Collection (NZAC): Diptera ” (Web Version 1 – June 1997)].

Macrocanace australis.— Tonnoir and Malloch, 1926: 5 [generic combination].— Harrison, 1976: 142 –143 [citation, southern islands of New Zealand subregion].

Apetaenus australis.— Mathis and Sasakawa, 1989: 667 [generic combination, Australasian/Oceanian catalog].— Mathis and Munari, 1996: 7 [World catalog].— Marris, 2000: 193 [citation, Campbell Island].— D.K. McAlpine, 2007: 30, 36–37 [SEM photographs of lower face and adjacent parts, fore basitarsus, acropod, and part of costa].

Macrocanace antipoda Harrison, 1953: 276 [Antipodes Island: Ringdove Bay (spider’s web); HT &, AMNZ]; 1959: 251 [synonymy].

Distribution. Australasian/Oceanian: Antipodes, Auckland, Campbell, and Snares islands.

Material examined. 53ɗɗ 71ΨΨ 2 undet. sex—NZAC—from Antipodes (Reef Pt, Stella Bay), Auckland (Adams Island), Campbell (Beeman Camp, De la Vire Pt, Tucker Cove), and Snares Islands (Biological Station, Seal Cove, Tern Point) were examined, all of them formerly determined and published as Macrocanace australis (Hutton) by Harrison (1976).

Other specimens examined. NZAC—Auckland Islands (Exp. 1972–73): Camp Cove, littoral rocks, seaweed beds, sweeping rocky shore, 8.ii. and 17.ii.1973, J. S. Dugdale, 6 ɗɗ 6 ΨΨ; Enderby Island, West of Sandy Bay, around shag [Phalacrocoracidae] nests on cliff faces, 26.ii.1973, J. S. Dugdale, 1 ɗ; Rose Island, on coastal rocks, 26.ii.1973, J. S. Dugdale, 1 Ψ; Tagua Bay, Carnley Harbour, supralittoral, 11.ii.1973, J. S. Dugdale, 2 ΨΨ. Snares Islands: Rima Islet, Western Chain, seal dung on rocks, 5 m, 21.xi.1976, J. W. Early, 1 ɗ; Sinkhole Gut, rotting Durvillea, high eulittoral zone, seal faeces on supralittoral rock, 14.vi. and 28.xii.1976, J. W. Early, 2 ɗɗ 1 Ψ; Station Cove, rotting Durvillea, seal dung on supralittoral rocks, at edge of mid-eulittoral tide pool, 25.ii.1975, 26.xi.1976, 9.i.1977, J. W. Early, D. S. Horning, 4 ɗɗ 4 ΨΨ.

LUNZ—Antipodes Island: Anchorage Bay, sweeping around rocks by penguin colony, 3.xi.1995, A. R. McIntosh, 3 ɗɗ; Hut Cove, ex yellow pan trap among herbs and ferns on coastal cliffs, 2-17.xi.1995, J. W. M. Marris, 2 ΨΨ.

Habitat and microhabitats. A thalassobiont fly with the same ecological preferences as the preceding species. It was recorded in the literature from the following microhabitats: on shore, ex spider web (Harrison, 1959); supralittoral beach drift, tussock, seaweed, seal and sea elephant wallows, shore rocks and cliffs, on supralittoral vegetation (Colobanthus, Stilbocarpa, Bulbinella, Hebe elliptica), kelp on beach, Enteromorpha, Bostrychia, algae, in supralittoral crustose lichen, Rockhopper Penguin rookery, on rocks in rookery, albatross carrion (Harrison, 1976). The female type of Macrocanace antipoda (= A. australis) was recorded by Harrison (1953) from a spider’s web. Additionally, the following habitats and microhabitats are herein newly reported (see material examined): high eulittoral zone, supralittoral, littoral rocks, seaweed beds, around shag nests on cliff faces, rotting Durvillea, seal faeces on supralittoral rock, at edge of mid-eulittoral tide pool, around rocks by penguin colony, ex yellow pan trap among herbs and ferns on coastal cliffs.

Remarks. This species differs from the related A. (Macrocanace) littoreus mainly by the following characters: body length of male <3.5 mm; postocellar setae present; postocular setae long and strong; face distinctly concave in lateral view; clypeus strongly protrudent, its distal margin sufficiently produced to be vertically beneath end of antennal postpedicel; scutum homogeneously brown; 1+4 dorsocentral setae (a few specimens exhibit variation, bearing second pair of setae, viz. first postsutural pair, poorly developed, tiny, weak); disc of scutellum with numerous, fairly long setulae, in particular on subapical portion, besides four long, strong scutellar setae; proepisternal seta often hardly discernible, tiny, hairlike; anepisternum with 3 posteromedian setae, mid seta long and strong, upper and lower setae short and thin (fig. 5); wing strongly darkened, with more or less irregularly infuscated wide areas (fig. 7) (a few specimens from Snares Islands show a distinctive dark patch on middle of wing, fig. 8); dorsal surface of vein R1 bearing 3–7 spinelike setae; mid and hind femora with at most 1–2 short, antero-dorsal setae on distal half, mostly indistinct and intermixed with moderately long setular vestiture; male terminalia (figs. 1–2) small; epandrium with sharp, ventral lobe bearing strong setae; surstylus long, paddle-shaped, broadly rounded apically, only bearing some thin setulae; cercus short, ovoidal; distiphallus narrow, slender, ribbon-like; female abdomen strongly telescopically retractile; tergite 1 of female longer than half of tergite 2, with markedly sclerotized, latero-ventral margins; sternite 2 about as long as entire syntergite 1+2, medially slightly membranous, with spinulose, sclerotized, longitudinal borders strongly converging posteriad; sternites 3–7 with indistinct, sparse, thin setae.