Marmasoma hortorum, Li & Yeates, 2018

Li, Xuankun & Yeates, David K., 2018, One hundred years of solitude ended: A second species of Marmasoma White, 1916 (Diptera, Bombyliidae, Bombyliinae, Eclimini) from Australia, Zootaxa 4420 (1), pp. 34-42 : 34-42

2. Marmasoma hortorum sp. nov.

( Figs 1–3 )

Type specimens. Holotype ♂ ( WAM), Australia, WA, 12km S Billabong Rdhse. [= Roadhouse], 9 Sep 1996, James O'Grady ( WAM: E97791 ) . Paratype ♀ (1), Australia, WA , same data as holotype ( WAM: E97792 ) .

Other specimens examined. Australia, WA, ♂ (2) ♀ (1), 12km S Billabong Rdhse., 12 Sep 1996, James O'Grady ( WAM: ♂ E97790 , E97793 ; ♀ E97789 ). ♂ (1) ♀ (1), 12km S Billabong Rdhse., 10 Sep 1996, James O'Grady ( WAM: ♂ E97795 ; ♀ E97794 ). ♂ (5) ♀ (1), Buntine, -29.9812 116.5691, Euc. trees + low shrubs, 11 Sep 2016, J & F Hort ( WAM: ♂ E97783 – E97784 , E97786 – E97788 ; ♀ E97785 ). ♂ (1), Northampton, -27.7862 114.8348, Low shrubs + yellow sand, 16 Sep 2016, J & F Hort ( WAM: E97782 ). ♀ (1), 11km SW Mt Leake, - 25.47 119.10, 16 Aug 1984, TF Houston & BP Hanich ( WAM: E97781 ). ♂ (1), Mullewa, Sep, LJ Newman ( WDFA: 73092) . SA, ♂ (1) ♀ (1), 62km N of Pt. Augusta , 2 Sep 1987, MG Jefferies ( ANIC No. 29- 041417, 29- 041418) .

Diagnosis. Wing with pale light markings. Body covered with mostly white to pale yellow scales. Male distiphallus straight, pointed posteriorly, subapex with long hairs. Female common spermathecal duct swollen.

Description. Male. Body length 10.0– 11.8 mm, wing length 7.4–9.0 mm.

Head. Head about 1.5 x wider than long, mostly blackish with thick pale pruinescence and covered in admixed white to pale yellow hairs and scales. Eye widely connected, by 2.8 x length of ocellar tubercle. Frons slender and long, upper triangular section small, lower triangular section black with thin pale pruinescence, middle narrow part about 0.6 x length of frons. Ocellar tubercle slightly raised, brown to blackish brown with grey pruinescence, with yellow hairs. Face with sparse pale pruinescence and otherwise bare, parafacial area blackish brown and bare. Gena with sparse pale pruinescence and long white to pale yellow hairs. Clypeus with sparse pale pruinescence and bare. Occiput with short white scales on eye margin and dense long white hairs admixed with some black bristles. Posterior eye margin slightly sinuous. Antennae black; pedicel with thin pale pruinescence, with short black hairs admixed with few yellow scales; scape with short black hairs and with long yellow ventral hairs. Scape 3.5 x as long as wide, and 3.5 x as long as pedicel, uniform from base to apex. Pedicel 1.1 x as long as wide. Flagellum 8.9 x as long as wide, 1.5 x as long as scape + pedicel (3.5 x as long as scape), conical and slightly laterally compressed, three-segmented with apical stylus ( Fig. 1c ). Palpus thin and long, extending beyond oral cavity, black with blackish brown hairs, two-segmented, with palpal pit. Mouthparts slender, 1.9 x as long as eye length (1.2 x as long as head length), labella thin and filiform ( Fig. 1f ).

Thorax. Integumental colour of scutum and scutellum mostly black with dense grey pruinescence, scutum with two black stripes, either side of midline. Scutum anterior half mostly with white scales admixed with long yellow and black hairs and some black scales, posterior half of scutum and scutellum with admixed white and black scales and long black hairs. Three notopleural setae present. Postalar callus and posterior margin of scutellum with strong hairs. Notopleural setae and strong hairs on postalar callus and scutellum black. Pleura black with thick grey pruinescence, anepisternum with long white scales admixed with strong yellow hairs, dorsal half of katepisternum with long white scales, metepisternum with moderately long white scales, laterotergite and mediotergite with dense long white hairs and strong yellow hairs, anepimeron and meron bare.

Legs. Legs black. Coxae with thick grey pruinescence. Femora mostly covered with white scales, except anterior and posterior faces of fore femur with brown scales. Tibiae covered with admixed white and brown scales. Mid femur with some long subapical black bristles, hind femur with two rows of long anteroventral black bristles. Other hairs and bristles on legs long and black. Fore tibia 2.2 x longer than fore basitarsus, mid tibia 2.5 x longer than mid basitarsus, hind tibia 2.3 x longer than hind basitarsus.

Wing. Wing membrane mostly hyaline, except the area around base of vein R 4, crossvein r-m, crossvein dm-cu, and apex of cell bm with light brown spot. Cell r 5 widely open; cell br much longer than cell bm, crossvein r-m arising apical half of cell dm; crossvein m-m long, and 1.5 x as long as crossvein r-m; cell cup open ( Fig. 1d ). Halter stem dark yellow, knob dark yellow.

Abdomen. Integumental colour of tergites black with thick grey pruinescence. Tergites mostly covered with pale yellow and black scales, pale yellow scales denser on lateral and posterior margin, black scales denser on central area. Tergite 1 with black hairs on posterior margin, tergites 4–8 with black ventrolateral hairs. Sternites with dark brown integumental colour, with white scales admixed with black hairs on posterior margin. Genitalia. Epandrium nearly rectangular, anterior margin with a deep notch, posterior margin slightly concave, anteroventral corner with long stem ( Fig. 3d ). Hypandrium absent. Gonocoxite slender and elongate. Gonocoxal apex as wide as the base in dorsal view, ejaculatory apodeme small ( Figs 3a, b ); gonocoxal apodeme strong and incurved; lateral ejaculatory process small; inner apex of gonocoxite rounded; outer apex of gonocoxite rounded; dorsal bridge without lateral hollow; gonostylus bifid apically, 1.5 x longer than wide; phallus long and strongly curved, subapex with long hairs ( Fig. 3c ).

Female. Body length 9.3–11.0 mm, wing length 7.1–9.1 mm. Very similar to male, except frons black with thick pale pruinescence, 2.5 x as wide as ocellar tubercle, frons with pale yellow hairs admixed with yellow and black bristles ( Fig. 2c ). Tergite 9+10 with some sparse hairs, 12 acanthophorite spines present, lateral spines long, spines in middle short. Furca straight and broad. Sperm pump strong and nearly as long as furca, clothed in longitudinal muscle, without lateral papillae; sperm pump apical and basal collars absent ( Fig. 3j ); common spermathecal duct swollen ( Fig. 3i ); spermatheca elongate, cylindrical with apex slightly swelled ( Fig. 3g ).

Remarks. Marmasoma hortorum sp. nov. is similar to Marmasoma sumptuosum , but differs as follows: wing markings light, inconspicuous; body covered with mostly white to pale yellow scales; male distiphallus straight, pointed posteriorly, subapex with long hairs; female common spermathecal duct swollen.

Distribution. Australia (SA, WA).

Etymology. This species is named in honor of Fred and Jean Hort for their important contributions to photographing and collecting Diptera specimens from Western Australia.

Figures

FIGURE 1 Marmasoma hortorum sp. nov. ♂: (a) dorsal; (b) lateral; (c) antenna, lateral; (d) wing; (e) head, dorsal; (f) head, lateral; (g) head, frontal; (h) head, profile. Scale bars = 1.0 mm (a, b, d–h); = 0.1 mm (c).

FIGURE 2 Marmasoma hortorum sp. nov. ♀: (a) dorsal; (b) lateral; (c) head, dorsal; (d) head, lateral; (e) head, frontal; (f) head, profile. Scale bars = 1.0 mm.

FIGURE 3 Marmasoma hortorum sp. nov. Genitalia (a–e (♂); f–j (♀)): (a) genital capsule, dorsal; (b) genital capsule, ventral; (c) genital capsule, lateral; (d) epandrium, dorsal; (e) epandrium, lateral; (f) apex of distiphallus, lateral; (g) sternite 8, ventral; (h) genitalia and spermathecae; (i) swollen of common spermathecal duct, ventral; (j) sperm pump. Scale bars = 0.1 mm.