Austropsyche acuta Wells & Contents 2018, sp. nov.
Creators: name: Wells, Alice
name: Contents, Arturs Neboiss Table Of
Publisher: name: Zenodo
Year: 2018
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Trichoptera
Hydropsychidae
Austropsyche
Austropsyche acuta

description: Austropsyche acuta sp. nov.
(Figs 59–60, 73, 78, 80–81, 83, 92, 100–101)
Material examined. Holotype ♂, New South Wales, Crystal Creek Rainforest Resort, Upper Crystal Creek, 26– 27.xii.2016, A. Wells (ANIC).
Paratypes, Queensland: 45♂ 13♀, Crystal Creek Rainforest Resort, Upper Crystal Creek, 28°15'S 153°15'E, 26–27.xii.2016, A. Wells; data as for holotype (ANIC); 4♂ 3♀, same locality, 26.xii.2006, A. Wells (NMV).
Other material examined. New South Wales: 1♂, Korumbyn Creek, 28°24'S 153°19'E, eastern slope of Mt Warning, 29.vi.1988, A. Neboiss; 2♂ 5♀, Orara West State Forest, Tucker's Knob, 29°41'S 152°48'E, 22.xi.1990, G. Theischinger; 13♂ 3♀, Upper Crystal Creek at Crystal Creek Rainforest Retreat, 28°15'S 153°15'E, 24.xii.2006, A. Wells; 18♂ 13♀, same locality, 25.xii.2006, A. Wells; 1♀, same locality, 22.xii.2016, A. Wells; 4♂ 3♀, same locality, 22.xii.2016, A. Wells; 42♂ 6♀, ♀, same locality, 25–26.xii.2016, A. Wells. SE Queensland: 1♂, Coomera Creek, Lamington NP, 8.ii.1961, F.A. Perkins [TRI-13850]; 1♂, Queen Mary Falls, Killarney, 12.x.1973, A. Neboiss; 1♂, Teviot Brook nr Wilson’s Peak, 18.xi.1980, M. Schneider; 1♂ Conondale Range, Bundaroo Creek, rainforest, 1.xii.1983, G. Cassis & D. Bickel [TRI-39868]; 8♂, same data [TRI-39499].
Diagnosis. This species forms a set with Austropsyche ambigua, here termed the Au. acuta Group, characterised by having the forewing median cell short, about equal in length to the discoidal cell; in the male genitalia, paired elongate sclerotised spines arise internally at the base of the deep apodeme connected to the gonopods and the mesal processes on the coxopodites arise apically, not subapically or basally. It is distinguished from Au. ambigua by having the apicomesal process on the coxopodite at least half length of harpago, needle-like, and subtended dorsally by a small conical lobe.
Description. Length of each forewing: ♂ 9.2–11.1 mm (n = 10), ♀ 11.4–12.2 mm (n = 9); cross-vein r-m anterad of cross-vein closing median cell.
Male. Abdomen swollen, internal sacs all elongate, each sack extending length of two segments; on segment V lateral filament length slightly less than length of segment (Fig. 83). Genitalia (Figs 59–60): Segment IX subquadrate, tergites IX and X partly fused; gonopods each with coxopodite almost equal width throughout length, narrow sharp process apicomesally, small conical dorsal lobe at base, harpago about length of coxopodite, elongate digitiform; phallic apparatus cylindrical, dilated apically, without endothecal spines; pair of elongate slender spines lateral to phallus, arising at base of apodemes connected to gonopods, converging apically.
Female. Abdominal segment VIII (Figs 100–101) with sternal plates separated, but indistinctly, tapered distally with apicolateral angles triangular; cerci and apical papillae on segment X relatively large, as for Au. victoriana.
Distribution. Found in north-eastern New South Wales and south-eastern Queensland. A single specimen in the NMV collection, PT-1041, labelled "NT, Alligator River", is almost certainly mislabelled as no other specimens of any diplectronine species have been taken from very far west of the Great Dividing Range, and no Austropsyche further north of south-eastern Queensland. The locality may have been Alligator Creek near Mackay, in central eastern Queensland; but even that is well north of any other collections of Austropsyche.
Remarks. Unlike males of most caddisfly species, males of Au. acuta are as large as, or larger than the associated females, and have sizeable, swollen abdomens. On dissection one finds that much of the abdominal cavity is occupied by the 2 pairs of reticulate-walled sacs. That, coupled with the fact that most of the light trap specimens collected in 2017 were male, leads to speculation that the sacs, which appear to be glands, may be involved in male-male attraction, in lekking behaviour.
description: Published as part of Wells, Alice & Contents, Arturs Neboiss Table Of, 2018, Australian Diplectroninae reviewed (Insecta: Trichoptera), with description of 21 new species, most referred to a new genus, pp. 1-44 in Zootaxa 4415 (1) on pages 16-18, DOI: 10.11646/zootaxa.4415.1.1, http://zenodo.org/record/1241736