Nothybus biguttatus Wulp

Lonsdale, O. & Marshall, S. A., 2016, Revision of the family Nothybidae (Diptera: Schizophora), Zootaxa 4098 (1), pp. 1-42 : 16-17

publication ID	https://doi.org/ 10.11646/zootaxa.4098.1.1
publication LSID	lsid:zoobank.org:pub:6A79B596-26E0-454B-8830-D69FFCBC4684
DOI	https://doi.org/10.5281/zenodo.6053686
persistent identifier	https://treatment.plazi.org/id/03C387D6-8A37-2251-EA84-6AD8EA9DF915
treatment provided by	Plazi
scientific name	Nothybus biguttatus Wulp
status

Treatment

Nothybus biguttatus Wulp View in CoL

Figures 17–21, 33–35, 68, 79–83

Nothybus biguttatus Wulp 1896: 112 View in CoL . Wulp 1896: 112 [illustrations of habitus, classified as “Calobatinen”]; Aczél 1955: 10 [family revision, key, description, illustration of head, thorax and terminalia, Java]; Frey 1958: 38 [Java]; Steyskal 1977: 30 [Oriental catalogue]; Galinskaya & Shatalkin 2015: 583 [ Vietnam, photos of adult, illustrations of male abdomen].

Description. Head: (Fig. 34) Base colour yellow with orange tint. First flagellomere black with base fading to brown on outer surface and with entire basal margin yellowish-orange. Frons with velvety posteromedial patch arrowhead-shaped, widest before anterior margin; anterolateral patches not reaching anterior margin of frons, extending along lateral margin to midpoint between posterior fronto-orbital and inner vertical; ocellar tubercle black with narrow brownish stripe continuing from tubercle to anterior third of frons. Face with dorsal 2/3 flat, minutely setulose, light yellow with thin, horizontal brown line below orange space in between antennal bases; ventral 1/3 white tomentose excluding shining brown medial tubercle that is shallower than that seen in most congeners; face more broadly dark brown in females. Labellum with blackish lateromedial spot; palpus brownish with ventrodistal margin and apex darker (often darker to mostly black in female).

Thorax: (Figs 33, 35) Dark yellowish-orange in base colour. Postpronotum dark brown and slightly iridescent dorsally (stripe much thicker anteriorly and posteriorly) and light yellow ventrally. Scutum with reddish-brown tint and with dark brown, ill-defined medial stripe bounded by 4 rows of setulae; postsutural scutum and lateral region of notopleuron darker. Dorsum of scutellum dark brown, lateral surface paler with margins orange, and venter orange with apex yellowish; subscutellum darker dorsally and yellowish ventrally, but sometimes mostly dark brown. Metanotum brown. Sclerites of pleuron brown with sutures sometimes paler, and with katepimeron and posterodorsal margin of katepisternum light yellow; meron and proepimeron sometimes yellowish-orange. Cervical sclerite brown to dark brown. Prosternum brownish. Eight rows of presutural acrostichal setulae in medial patch; lateral patch of 2–3 additional rows of setulae clearly delimited.

Wing: ( Fig. 68 View FIGURES 67 – 78 ) Wing length 8.8–10.4mm. Clouded, slightly more so along anterior margin; r-m surrounded by dark brown cloud; oblique brown medial band (from costa to CuA1 along dm-cu) largely fused to dark apical margin, filling apices of cells r1 to r4+5; cells r2+3 and r4+5 with clear, iridescent subapical spots, with anterior spot slightly more distal. Dark apical margin sometimes expanded slightly to significantly along veins as larger spots that may partially to mostly envelop clear spots. Base of R4+5 with several very small, thin hair-like setulae ventrally. Margin of calypter brown. Halter light brown, base of stem dark.

Legs: Mostly yellowish-orange. Base of fore coxa brown, venter of mid coxa brown and hind coxa with brown mottling. Apices of femora dark brown with pigment more extensive on inner surface. Tibiae dark brown with base paler (narrowly so on mid and hind legs). Tarsi dark brown with middle third of fore basitarsomere light yellow to white (band broader and paler in female).

Abdomen: Base colour dark brown to brown with orange tint. Tergite 1 with one pair of sublateral orange spots. Sternite 1 yellowish-orange; sternites 2–5 dark brown with yellow medial stripe; tergites brown to dark brown, but some females with centre of tergite 1 brown, tergites 2–7 brown with margins thinly yellow, and tergite 8 to cercus yellowish-orange. Tergites 2–5 with dark velvety posteromedial patch and tergite 5 with lateral velvety patch sometimes covering most of sclerite. Epandrium dark brown and posterior margin of sternite 8 paler to orange posteriorly.

Male terminalia: ( Figs 79–83 View FIGURES 79 – 83 ) Tergite and sternite 6 relatively long, broad and setose. Sternite 7 membranous, evident as one pair of sensory setulae near margins of dorsal, setose, band-like sternite 8. Epandrium relatively short, broad. Surstylus narrow, more than twice height of epandrium, longitudinally striated, with minute apical setae. Cercus finger-like, nearly as high as surstylus. Subepandrial sclerite fused to surstylus at base; similar in height to surstylus and with apical tubercle-like setae. Hypandrium with lateral lobes broad, with few ventromarginal setae and with more numerous laterobasal setae that extend onto small rounded dorsobasal process. Pregonite pale, tapering apically and with two large lateromedial setae. Distiphallus fused to basiphallus, not longer than hypandrium, mostly composed of one pair of dark flat coiled ribbons that are produced distolaterally on membrane as one pair of short spines. Ejaculatory apodeme with dark, stout, asymmetrical base approximately as long as stem; stem thicker along centre, becoming more heavily sclerotized on one side towards apex; blade narrow at base, broad and clear apically.

Female terminalia: (Figs 17–21) See above under “Definition of Nothybidae ”.

Variation—Java: Paler overall but mostly with same underlying pattern; abdomen brownish-orange, being darker medially and with black pigment in velvety posteromedial patches; sometimes with posterior margins of tergites orange and with pronounced orange tint sublaterally, particularly towards anterior and posterior margins.

Variation—northern Vietnam: The female from northern Vietnam examined here, and the northern Vietnamese material described and imaged in Galinskaya & Shatalkin (2015) differ as follows: Pigment darker and more extensive, mostly reddish-brown or dark brown to black. Face more broadly black, clypeus brown, palpus entirely black, labellum darker. Lateral margin of notopleuron and mediotergite, and anterior margin of katatergite black. Mid femur with broad, ill-defined brown band past midpoint and basal section paler; hind femur sometimes also with dark medial band that is narrower and more ill-defined; white region of fore basitarsomere extending nearly to end of segment. Abdomen mostly black, dorsomedial region of female tergite 7 and terminalia dark orange. Wing pigmentation similar to, or slightly darker than “typical” specimens, wings darker with more extensive brown spots extending along apex of veins, nearly enclosing clear iridescent spots; wing length 7.0mm in specimens examined by Galinskaya & Shatalkin (2015).

Distribution. Indonesia (Java, Sumatra), Nepal, Vietnam.

Syntypes: INDONESIA. Java: Gunung Gede, Tjibodas (ST ♂♀, ZMAN [lost]).

Additional material examined. INDONESIA. Java: W Java, Tjipanas, 5–10000, 8.vi.1965ʹ, J.E. Lukavsky (1♀, CNC), 8.viii.1965 (1♂, CNC), Java: Tjibodas, 4000ft, i.1936, L.E. Cheesman, B.M. 1936–89 (1♂ 2♀, BMNH), Java, Tybodas, Terry coll. (2♂ 1♀, BPBM), Java: Sindaglaija, F. Muir, 4000–4500 ft (1♂ 2♀, BPBM), West Java: Mt. Gede, Lebak Sive, 4,500′, ix.1938, B.M.1962-651 (1♀, BMNH), Sumatra: Sungei Kumbang, Korinchi, 3,500ft. Apl., 1914, 1915 [handwriting], 182 [handwriting] (1♂, BMNH). NEPAL. Taplejung Distr.: between Sangu and Tamrang, x–xi.1961, mixed shrubs in deep gorge c. 5200’, Brit. Mus. East Nepal Exp., 1961- 62, R.L. Coe Coll., B.M. 1962-177 (1♀, BMNH). VIETNAM. N Vietnam: Phu Tho Prov., Xuan Son National Park, 500m, 13–17.vi.2010, L. Bartolozzi & S. Bambi (1♀, MZUF). No collection data. (1♂, 2?[terminalia destroyed], BPBM).

Comments. Specimens of this species from northern Vietnam have darker pigmentation than specimens from Indonesia and Nepal, but are otherwise uniform in external and male genitalic structure. Nothybus biguttatus is here recorded from Nepal for the first time. See comments for N. acrobates .