Helius (Helius) flavus ( Walker, 1856 )

Lv, Hanhuiying, Xu, Yuanyuan, Zhao, Yufei, Lin, Kejian & Zhang, Xiao, 2024, New records for the Helius Lepeletier & Serville fauna (Diptera, Limoniidae) of China, Biodiversity Data Journal 12, pp. e 115775-e 115775 : e115775-

Helius (Helius) flavus ( Walker, 1856)

Rhamphidia flava Walker, 1856 - Walker (1856): 309.

Helius flavus ( Walker, 1856) - Starý (1966): 86.

Helius (Helius) flavus ( Walker, 1856) - Podenas et al. (2017): 272.

Materials

Type status: Other material. Occurrence: recordedBy: Xingyang Qian; individualCount: 4; sex: 2 males, 2 females; lifeStage: adult; occurrenceID: 95CD7DBB-9F0D-5B03-A9E5-7B85ACC3ADE7; Taxon: scientificName: Helius (Helius) flavus ( Walker, 1856) ; order: Diptera ; family: Limoniidae ; genus: Helius ; subgenus: Helius ; Location: country: China; stateProvince: Inner Mongolia; county: Ningcheng; locality: Heilihe National Nature Reserve, Xidaliang ; verbatimElevation: 1070 m; decimalLatitude: 41.399511; decimalLongitude: 118.361483; Event: samplingProtocol: sweeping; eventDate: 30 - Jul- 22; Record Level: institutionCode: QAU

Description

Diagnosis. Antenna with basal flagellomeres oval. Rostrum about 1.2 times as long as remainder of head. Prescutum and presutural scutum yellow, darker at anterior third. Femora brownish-yellow, darkened at tip. Wing with apex slightly darkened, stigma inconspicuous. Venation with Sc ending opposite about 3 / 4 of Rs, cell dm about twice as long as wide, m-cu beyond fork of M. Posterior margin of tergite 9 with a broad and deep V-shaped notch. Outer gonostylus with tip black and bifid. Inner gonostylus expanded near middle and bent inwards at a right angle, distal part slender; outer margin of expanded lobe with five teeth. Interbase distally horn-shaped, tip suddenly thinning into a spine. Aedeagus rod-shaped, tip slightly expanded and rounded.

Male (Fig. 2 A). Body length 7.1–7.3 mm (excluding rostrum), wing length 7.5–7.7 mm, rostrum length 0.9–1.0 mm, halter length 1.1–1.3 mm.

Head (Fig. 2 B). Brownish-black. Setae on head dark brown. Antenna with scape dark brown, pedicel yellow to pale brownish-yellow, flagellomeres brown with basal segments yellow to pale brownish-yellow. Scape cylindrical, 2.5 times as long as wide. Pedicel oval, tip slightly enlarged. Flagellomeres 1–3 oval; remaining flagellomeres cylindrical, tapering apically and elongated, with dark brown verticils. Rostrum about 1.2 times as long as remainder of head, dark brown with brownish-black setae. Palpus dark brown with brownish-black setae.

Thorax (Fig. 2 C). Pronotum dirty yellow with middle area brown. Prescutum and presutural scutum yellow, darker at anterior third, dorsally a pair of yellow stripes bordered by brown dots and separated by narrow pale line. Postsutural scutum pale yellow, each lobe with oval area bordered by dark spots. Scutellum and mediotergite yellow. Pleuron yellow to brownish-yellow (Fig. 2 A). Setae on thorax dark brown. Coxae brownish-yellow; trochanters brownish-yellow with fore trochanter slightly paler; femora brownish-yellow, darkened at tips; tibiae pale brown with tips dark brown. Setae on legs brown. Wing (Fig. 2 D) pale brown with base and costal area yellow, wing apex slightly darkened; stigma inconspicuous. Veins brown. Venation: Sc ending opposite about 3 / 4 of Rs, sc-r near tip of Sc; m-m shorter than basal section of M 3; cell dm about twice as long as wide; m-cu about 1 / 3 of its length beyond fork of M. Halter pale yellow.

Abdomen. Tergites yellow to brownish-yellow. Sternites 1–6 yellow, sternite 7 brownish-yellow with caudal third brown, sternite 8 brownish-yellow with a brown spot at middle, sternite 9 brownish-yellow. Setae on abdomen brown.

Hypopygium (Fig. 3 ). Generally yellow. Posterior margin of tergite 9 with a broad and deep V-shaped notch (Fig. 3 A). Gonocoxite cylindrical, tip round, base with a stout spinerous lobe (Fig. 3 A and B). Outer gonostylus nearly straight; tip black and bifid, outer spine slightly bent, inner spine triangle (Fig. 3 A, B and E). Inner gonostylus expanded near middle and bent inwards at a right angle, distal part slender; outer margin of expanded lobe with five teeth (Fig. 3 A, B and E). Interbase distally horn-shaped, tip suddenly thinning into a spine; base horizontally extended (Fig. 3 A, C and D). Parameres sheet-like, medially fused, apically elongated and connecting to base of interbase (Fig. 3 C and D). Aedeagus rod-shaped, tip slightly expanded and rounded, base expanded (Fig. 3 A – D).

Female (Fig. 4 ). Body length 9.6–10.2 mm (excluding rostrum), wing length 8.7–9.2 mm, rostrum length 1.1–1.2 mm, halter length 1.3–1.4 mm. Generally similar to male by body colouration, except abdomen with segments 7 and 8 yellow. Ovipositor with tergites 9 and 10 yellow (Fig. 4 A and B). Cercus brownish-yellow, slightly darker at subtip, tip raised and acute (Fig. 4 A and B). Hypogynial valve yellow to brownish-yellow, nearly straight, tip reaching slightly beyond middle of cercus (Fig. 4 B and C).

Distribution

China (Inner Mongolia); Austria, Belarus, Belgium, Bulgaria, Czech Rep., Denmark, Finland, France, Germany, Great Britain, Hungary, Ireland, Italy, Kazakhstan, Lithuania, Malta, Netherlands, North Caucasus, North Macedonia, Norway, Poland, Romania, Russia, Serbia, Slovakia, South Korea, Sweden, Switzerland, Ukraine ( Oosterbroek 2023).

Notes

Helius (H.) flavus is widely distributed in the Palaearctic Region ( Oosterbroek 2023) and recorded in China for the first time. Walker (1856) first discovered this species and provided a brief description without figures and Starý (1966) illustrated the female ovipositor for the first time. Subsequently, Starý and Rozkośný (1970), Geiger (1986), Podenas et al. (2006), Podenas et al. (2017) and Quindroit (2022) successively illustrated this species, amongst which Podenas et al. (2017) provided detailed description and illustrations of the male for this species. The species is closely related to H. (H.) unicolor ( Brunetti, 1912) in the key by Xu et al. (2023) and can be distinguished by the inner gonostylus with five teeth on the outer margin of the middle (Fig. 3 A, B and E). In H. (H.) unicolor , the inner gonostylus has no teeth ( Brunetti 1912).

Figures

Figure 2. Helius (Helius) flavus (Walker, 1856). A habitus of male, lateral view; B head, lateral view; C thorax, dorsal view; D wing. Scale bars: 2.0 mm (A); 0.5 mm (B, C); 1.0 mm (D).

Figure 3. Helius (Helius) flavus (Walker, 1856). A male hypopygium, dorsal view; B male hypopygium, ventral view; C aedeagal complex, dorsal view; D aedeagal complex, ventral view; E outer gonostylus and inner gonostylus, dorsal view. Scale bars: 0.2 mm (A, B); 0.1 mm (C, D, E).

Figure 4. Helius (Helius) flavus (Walker, 1856). A female ovipositor, dorsal view; B female ovipositor, lateral view; C female ovipositor, ventral view. Scale bars: 0.5 mm (A, B, C).