Hexatoma (Eriocera) ussuriensis Alexander, 1934

Podenas, Sigitas, Park, Sun-Jae, Byun, Hye-Woo & Podeniene, Virginija, 2022, Hexatoma crane flies (Diptera, Limoniidae) of Korea, ZooKeys 1105, pp. 165-208 : 165

Hexatoma (Eriocera) ussuriensis Alexander, 1934

Figs 50-53 , 66

Hexatoma (Eriocera) ussuriensis Alexander 1934a: 341-343, pl. 1, fig. 22, pl. 4, fig. 49; Savchenko 1983: 68 (short note on distribution); 1989: 123 (short note on distribution); Przhiboro et al. 2009: 221-228 (distribution and habitats); Podeniene and Gelhaus 2015: 107-112 (descriptions of larva and pupa), figs 39-53.

Type material examined.

Paratypes: Russia, male (antenna, fore leg, wing, and genitalia slide-mounted), E. Siberia, Ussuri, Bikin, river Bikin, 8 July 1927, Martynov leg. (USNM); 1 specimen, sex unknown (pinned), Ussurian district, river Bikin, station Bikin, 8-9 July 1927, Martynov leg. (USNM); 1 male (pinned), same collection data as for preceding, 9 July 1927 (USNM).

Other examined material

(Fig. 66 ). North Korea, teneral male (pinned), Prov. South Pyongan, Pyongyan, Hotel garden, 5 August 1971, No 141, S. Horvatovich et J. Papp leg. (HNHM) .

Description.

Body coloration gray to dark brown (Fig. 50 ). Male body length 7.5 mm, wing length 12.5 mm.

Head. Brownish gray, narrowly pale gray along eye margin, covered with whitish erect setae. Vertical tubercle very large, rounded, brown, dusted with grayish yellow postero-dorsally, without polished black summit mentioned in original description ( Alexander 1934a), polished black area also missing in studied topotypic paratypes. Tubercle reaches beyond middle of scape. Eyes widely separated, distance between them at base of antennae equal to length of scape and pedicel taken together. Male antenna 18.9 mm long, distinctly longer than the entire body. Scape very large, elongate, obscure yellow with darkened and dusted dorsal surface. Pedicel very short, ring-shaped, yellow. Flagellum black with base of first flagellomere narrowly brownish. Flagellomeres with two parallel rows of short spines. Basal flagellomere 4.2 mm long, with 19 spines in each row and sparse short whitish pubescence between them, second flagellomere 6.0 mm long with 24 spines, third flagellomere 7.2 mm long with 21 spines. Rostrum brownish yellow with few long erect setae dorsally, palpus dark brown to blackish, labella black.

Thorax. Cervical sclerites brown, dusted with gray. Pronotum much wider than long, dark brown with gray dusting. Prescutum and presutural scutum gray with four distinct dark brown longitudinal stripes and covered with comparatively sparse long whitish setae. Area separating medial stripes slightly narrower than the stripes themselves. Tubercular pits missing, pseudosutural fovea small, polished-brown. Postsutural scutum with each lobe gray with dark brown central area, which also dusted with gray. Area between lobes dark brown anteriorly, pale posteriorly. Scutellum gray with pale fronto-lateral angle. Mediotergite brown, dusted with gray. Pleuron gray, posterior margin of anepimeron with dense long yellowish setae. Wing (Fig. 51 ) slightly iridescent, with pale brownish tinge, yellowish in costal area and at base. Stigma distinct, oval, dark brown. Small but distinct dark spot surrounds axillary vein at wing base. Cord, distal margin of discal cell and distal longitudinal veins surrounded by indistinct brownish areas. Veins brown, yellowish at wing base. Macrotrichiae on distal veins missing. Venation: humeral vein slightly beyond arculus, Sc very long, reaching wing margin distinctly beyond r-m but before branching point of R2+3 and R4, sc-r at the level of r-m. Rs long and nearly straight, arched at base. Free end of R1 oblique, R2 and R2+3 equal in length. R3 and R4 diverging, cell r3 with long stem, which is approximately half length of Rs. Cross-vein r-m distinct, slightly oblique, in alignment with basal deflection of M1+2 (base of discal cell). Discal cell 1.5 × longer than wide. Cross-vein m-cu very slightly beyond base of discal cell (branching point of M). Vein CuP distinctly curved at distal part, thus cell cua gets wider towards wing margin, but nearly parallel-sided from base to ~ 2/3 of its length. Anal vein long, slightly concave at middle, apex at same level as Rs base. Anal angle wide, posterior margin widely rounded. Stem of halter pale to brownish, knob dark brown. Length of male halter 1.2 mm. Coxae from brown dorsally to yellow ventrally, covered with gray pruinosity and long yellowish setae. Trochanters obscure yellow. Femur yellow with narrowly dark brown apical part. Tibia yellowish brown with narrowly darkened apex. Tibia of fore leg with single apical spur, tibiae of middle leg with two apical spurs. Tarsus brown at base, dark brown at distal end. Male femur I: 3.2 mm long, II: 4.5 mm, III: 7.5 mm, tibia I: 7.5 mm, II: 5.7 mm, tarsus I: 7.0 mm. Claw yellowish brown with subbasal spine.

Abdomen. Two basal tergites brown, remaining dark brown with narrowly brownish yellow lateral margins. Three basal sternites grayish brown, remaining getting darker towards apex, lateral margins brownish to grayish yellow. Abdominal segments covered with long whitish setae, that are denser laterally. Male terminalia (Figs 52 , 53 ) brownish, ninth segment narrower than rest of the abdomen. Epandrium wider than long, posterior margin with wide V-shaped emargination. Gonocoxite elongate, nearly 3 × as long as wide at base, dorsal surface with lighter transverse area at middle which extends from less sclerotized mesal surface. Two pairs of long narrow gonostyli. Outer gonostylus sclerotized, long, slightly arched, apex distinctly narrowed and spine-shaped, mesal surface with small serration distally. Inner gonostylus elongate, fleshy and setose, apical part distinctly narrower, rounded apex. Paramere with two lobes, dorsal lobe wedge-shaped, ventral lobe elongate with rounded distal margin. Aedeagus simple, short, and straight, apex just slightly protrudes beyond frontal margin of aedeagal sheath in dorsal view. Anterior apodeme long and narrow, without lateral lobes, extending far forward.

Elevation range.

Ca. 20 m in Korea. 30 m to 650 m in Russia, Japan, and Mongolia ( Przhiboro et al. 2009).

Period of activity.

Beginning of August in Korea. June-July in Russia, Japan, and Mongolia ( Przhiboro et al. 2009).

Habitat.

Unknown in Korea. Shores of different types of running waters, from shores of large- and medium-sized rivers on plains to medium-sized and small rivers in the foothills in boreal forest, mixed forest, forest-steppe, and steppe landscape zones in Russia and Mongolia ( Przhiboro et al. 2009). Both sexes are attracted to light ( Przhiboro et al. 2009). Larvae of this species develop only on the bottom of large and medium sized rivers. Last instar larvae and pupae can be found in the riparian zone, usually in gravel, sand or under stones in Mongolia ( Podeniene and Gelhaus 2015).

Distribution.

Eastern part of Russia, Mongolia and Hokkaido Island, Japan. Recorded on the Korean Peninsula for the first time.

Figures

Figures 50 - 53. Hexatoma (Eriocera) ussuriensis Alexander, 1934 50 male, dorsal view 51 male wing 52 male genitalia, dorsal view 53 male genitalia with ninth segment removed, dorsal view. Scale bars: 1.0 mm (50, 51); 0.5 mm (52, 53).

Figures 59 - 66. Sampling localities of Korean Hexatoma (Eriocera) 59 H. (E.) gifuensis Alexander, 1933 60 H. (E.) ilwola sp. nov. 61 H. (E.) masakii Alexander, 1934 62 H. (E.) pernigrina Alexander, 1938 63 H. (E.) pianigra sp. nov. 64 H. (E.) serenensis sp. nov. 65 H. (E.) stackelbergi Alexander, 1933 66 H. (E.) ussuriensis Alexander, 1934.