Skuseomyia eximia Alexander, 1924

Billingham, Zacariah D. & Theischinger, Gunther, 2022, New and Poorly Known Species of Crane Flies (Diptera: Limoniidae) from New South Wales, Australia, Records of the Australian Museum (Rec. Aust. Mus.) 74 (1), pp. 19-40 : 30

Skuseomyia eximia Alexander, 1924

Figs 24–28

Material examined. New South Wales: 2♀♀, Dorrigo National Park , 11 Nov 1967, N. Dobrotworsky ( ZB) ; 1♂, Chichester, Whitehouse Creek off Wangat Rd (32.120°S 151.681°E), 8 Nov 2018, Z. Billingham & G. Theischinger, GHD ( T 24276) . Queensland: 1♀, Binna Burra , 9 Dec 1966, N. Dobrotworsky ( ZB) ; 1♀, Cunninghams Gap , 5 Apr 1967, N. Dobrotworsky ( ZB) ; 1♀, Maleny , 6 Apr 1967, N. Dobrotworsky ( ZB) .

Remarks. Alexander (1924) had only two female specimens of Skuseomyia eximia available when describing the species, leaving the male undescribed. A full account of the male is now possible with the availability of fresh material.

Photographs are included to show the dorsal thoracic colouration ( Fig. 24 ), wing patterning ( Fig. 25 ) and the ovipositor ( Fig. 28 ). Figures of the wing venation ( Fig. 26 ) and dorsal view of the hypopygium ( Fig. 27 ) is also provided.

Male. Similar in size to female. Head pale yellowish white, faintly darker grey at the vertex. Antenna with scape yellowish white, pedicel greyish yellow, flagellomeres greyish yellow, darkening to brownish towards the tips, palpus greyish yellow. Pronotum and prescutum yellowish white; scutum largely yellowish white with median greyish brown line extending to the transverse suture, prominent deep black cross band along the transverse suture, scutal lobes largely brownish yellow, lateral angles pale yellowish white; scutellum pale yellowish brown anteriorly, yellowish white posteriorly; mediotergite greyish brown medially, lateral edges darker grey ( Fig. 24 ). Pleurites largely yellowish white, the anterior angle of katepisternum and dorsal edge of laterotergite greyish brown. Coxae yellowish white, anterior angles faintly darker greyish brown; trochanters yellowish white; femora yellowish, darkening faintly to brown towards the tips; tibiae yellowish, tarsi darkening to brown. Wing hyaline with extensive patterning; a greyish to orange transverse streak through c and along Sc; an elongate brownish orange transverse streak arising in the distal section of r1 running along the wing margin, encompassing all of r2, nearly half of r3, the tips of r4 and r5 and terminating in m1, anterior and posterior boarders intermittently seamed with dark grey to black; an elongate brownish orange transverse streak arising at the base of br and running along R, encompassing the origin of Rs and extending to the “step-like” curve of Rs, there expanding into an ovoid patch, boarders intermittently seamed with dark grey to black; an elongate brownish orange longitudinal streak arising at the tip of Sc and extending along the bases of R 2+3, R 4 and R 5, along r-m and the base of the discal medial cell to terminate on M, boarders intermittently seamed with dark grey; small dark grey to black marking at the base of bm extending as a dark seam along much of M; an elongate brownish orange longitudinal streak that darkens posteriorly to greyish brown arising in the basal ⅓ of r5 and extending along the distal end of the discal medial cell and m-cu to terminate at the tip of CuP; a narrow orange streak along much of CuA; a dark greyish brown circular marking at about half the length of cup ( Fig. 25 ). Sc long, extending beyond the fork of Rs, sc-r at its tip, Rs straight with a “step-like” curve near mid length, R 2+3+4 a little shorter than the base of R 5, R 2+3 a little shorter than R 3, R 4 and R 5 of similar length, base of R 5, r-m and base of discal medial cell in near alignment, discal medial cell closed, cell m 1 present, a little longer than its petiole, m-cu situated a short distance before the distal end of the discal medial cell, CuP elongate, its tip somewhat close to the tip of CuA, A 1 quite straight, curving faintly at the tip ( Fig. 26 ). Halter elongate, extending back to the posterior margin of the second abdominal segment, stem pale greyish, knob a little darker. Abdomen with first tergite yellowish brown, lateral edges darker greyish, second tergite largely yellowish with a pair of small greyish brown markings in posterior half, tergites 3–7 yellowish with subterminal dark greyish brown marking, in some individuals forming a near complete crossband, in others broken medially, eighth tergite dark brown to black, posterior margin broadly concave. Hypopygium ( Fig. 27 ) with ninth tergite and sternite dark brown to black, gonocoxites light greyish brown. Distal margin of T9 drawn out into a pair of curved spinous processes, giving the area between them the appearance of an ovoid excision. Gonocoxite a little longer than T9, quite broad, at base on medial surface with a dense brush like patch of short setae, on ventromedial edge towards tip with short triangular process. Outer gonostylus blade like, tip blunt, acute, a prominent circular lobe towards the base of the style. Inner gonostylus strongly hooked towards tip, medial surface with deep groove accommodating the outer gonostylus, distal edge with a low flange bearing numerous short bristle-like setae. Interbase with base broad, circular and plate like, on distal edge with a low, strongly hooked branch, extended to a sharp pointed tip. Aedeagal complex not extending much beyond the brush-like patch of setae on the gonocoxites, with broad, quadrate, somewhat membranous lateral plates at base, seemingly formed by the parameres, narrowing considerably in the distal ⅓ to a conical, faintly bilobed tip.

Female. Ovipositor ( Fig. 28 ) yellowish brown. Cercus of moderate length, strongly arched dorsad. Tip of hypogynial valve reaching to about ½ length of cercus.

Discussion. The monotypic Skuseomyia is remarkably distinct among the Australian limoniid fauna and readily recognized by the deep black cross band along the transverse suture, characteristic wing patterning and peculiar wing venation, with Rs curved “step-like” at about mid length.

Figures

Figures 24–28. Skuseomyia eximia (24) thoracic colouration, dorsal; (25) wing pattern; (26) wing venation; (27) hypopygium, dorsal view, with aedeagal complex and ventral gonocoxite inset; (28) ovipositor, lateral.