Dicranomyia globithorax Osten Sacken, 1869 (original designation).

Rostrum is very short or reduced. Number of palpomeres ranges from one to three. Wings have no patterns, even in stigmal region. Third and fourth tarsomere are slightly swollen. Internal sac or notch is located on the male seventh sternite. Gonocoxite has ventromesal lobe. Gonostylus is one paired, with one or two setae arising from small tubercle on outer surface.

Holotype : Korea • ♂; Jeju-do, Seogwipo-si, Namwon-eup, Sillye-ri, Iseungi-oreum Volcanic Cone; 33°20.24'N, 126°37.25'E; alt. 450 m; 4 Aug.–8 Sep. 2021; Y. J. Bae leg.; Malaise trap; GenBank: OM102981; CF21-0150H; NIBR.

Paratypes : Korea • 1 ♀; same data as holotype, 14 Jul.–4 Aug. 2021; GenBank: OM102983; CF21-0151; KUEM • 1 ♂; same data as holotype; GenBank: OM102982; CF21-0150P; KUEM.

Palpus is 3-segmented. Male seventh sternite has shallow V-shaped notch. Outer face of gonostylus has single seta arising from tubercle. Distal lobe of paramere has a hooked tip with a subapical process.

Male (holotype). Body length 4.3 mm, wing length 4.6 mm, antenna length 0.9 mm. General body coloration pale yellow to yellowish brown (Fig. 1A).

Figure 1. 

Dicranomyia (Erostrata) jejuensis sp. nov. A habitus, male (paratype) B head, female (paratype) C wing, male (paratype) D male seventh sternite, ventral view E male terminalia, dorsal view F aedeagal complex, dorsal view G paramere, lateral view H female terminalia, lateral view I tip of hypovalva, lateral view. Abbreviations: ad – aedeagus; cc – cercus; fl – flagellum; gc – gonocoxite; gf – genital fork; gs – gonostylus; hv – hypovalva; pd – pedicel; pl – palpus; pm – paramere; sc – scape; tb – tubercle; t9 – ninth tergite; vlg – ventromesal lobe of gonocoxite. Scale bars: 2 mm (A, C); 0.5 mm (B, D, E, H); 0.1 mm (F, G, I).

Head (Fig. 1B). Dark brown dorsally, pale ventrally. Antennae 14-segmented; scape pale yellow; pedicel yellowish brown; flagellum brown. Rostrum pale, rudimentary. Palpus 3-segmented; basal 2/3 of first palpomere pale; remainder of palpus brown.

Thorax. Prescutum and presutural scutum yellow. Postsutural scutum, scutellum and mediotergite yellowish brown. Pleuron uniformly dull yellow, without lateral stripes. Wing (Fig. 1C) tinged with pale brown; veins brown; Sc ending before middle of Rs; sc-r at tip of Sc; Rs arched at base; R₁ and R₂ nearly transverse, at the same level; R₃ and R₄₊₅ parallel to each other; discal medial cell closed; m-cu before fork of M; CuP ending beyond tip of Sc. Halter pale brown. Legs with coxae and trochanters pale; base of femora pale, remainder of femora brown; tibiae and tarsi brown. Femur II 3.3 mm; femur III 3.8 mm; tibia II 3.5 mm; tibia III 4.0 mm; tarsus II 3.2 mm; tarsus III 2.8 mm. Claw without additional tooth.

Abdomen. Tergites yellowish brown, sternites 1–4 yellow, remaining yellowish brown. Seventh sternite with shallow V-shaped notch with darkened margin (Fig. 1D).

Male terminalia (Fig. 1E–G). Yellow. Ninth tergite with posterior margin rounded (Fig. 1E), medially with distinct emargination, distal part covered with setae. Gonocoxite elongated, approximately 3× as long as width at base, with elongated, setose ventromesal lobe. Gonostylus yellowish brown at base, turning dark distally; distal 1/2 of gonostylus gradually tapered toward apex, with short black spine at tip; dorsal margin near the base with small tubercle bearing pale, stout seta. Paramere (Fig. 1F, G) with basal 1/2 pale and apical 1/2 yellowish, distal lobe darkened apically with hooked tip and subapical projection. Aedeagus (Fig. 1F) as long as gonocoxite, bifid, curved outwards at tip.

Female. Body length 4.5 mm, wing length 4.8 mm, antenna length 0.9 mm (N = 1). General body coloration brighter than male. Femur I 2.8 mm; II 3.2 mm; III 3.4 mm; tibia I 3.2 mm; I: 3.1 mm; III 3.4 mm; tarsus I 3.0 mm; II 2.6 mm; III 2.4 mm.

Female terminalia (Fig. 1H–I). Yellow. Cercus curved upwardly (Fig. 1H), wider at base, narrowing towards acute tip. Genital fork long, ca 1.5× as long as width, extending to base of cercus. Hypovalva wedge-shaped, reaching to ca 2/3 of cercus, with distinct black spot at base. Dorsal and ventral margin of hypovalva serrated near tip (Fig. 1I).

Specific name “jejuensis” refers to the type locality, Jejudo Island, Korea.

The species is currently only known from Jejudo Island, Korea.

Adults of this species are found in deciduous forests with moss-covered rocks along intermittent, rocky mountain streams (Fig. 2) and co-occur with D. (E.) submelas.

Figure 2. 

Habitat of Dicranomyia (Erostrata) jejuensis sp. nov.

Adults were collected from June through early September.

Dicranomyia (E.) jejuensis sp. nov. is morphologically similar to D. (E.) yazuensis based on the male genital structures, but it can be distinguished by the following characters: pleuron entirely dull yellow (vs dark dorsally); palpus 3-segmented (vs 2-segmented); distal 1/2 of gonostylus tapered to tip (vs distal 2/3 strongly narrowed toward tip); posterior margin of male seventh sternite with shallow V-shaped notch (vs long triangular notch); distal part of paramere with hooked tip (vs straight tip).

Holotype : Korea • ♂; Jeju-do, Seogwipo-si, Hawon-dong, Mt. Hallasan; 33°20.95'N, 126°29.72'E; alt. 1220 m; 13 Jun.–4 Aug. 2021; Y. J. Bae leg.; Malaise trap; GenBank: OM102979; CF21-0148; NIBR.

Paratypes : Korea • 1 ♂; Gyeonggi-do, Gapyeong-si, Buk-myeon, Jeokmok-ri, Garim-gyo (Br.); 37°58.60'N, 127°26.55'E; alt. 300 m; 25 Jul.–1 Aug. 2015; Y. J. Bae leg.; Malaise trap; published as D. (E.) tabashii by Podenas et al. (2019); KUEM • 2 ♂♂, 1 ♀; same data as for preceding; 2–8 Aug. 2015; published as D. (E.) tabashii by Podenas et al. (2019); KUEM • 1 ♂; same data as for preceding; 23–29 Jul. 2016; published as D. (E.) tabashii by Podenas et al. (2019); KUEM • 1 ♂; Gangwon-do, Inje-gun, Girin-myeon, Bangdong-ri, Mt. Bangtaesan; 37°54.50'N, 128°24.41'E; alt. 690 m; 30 Jul.–16 Sep. 2019; Y. J. Bae leg.; Malaise trap; KUEM • 1 ♂; Gyeonsangnam-do, Sancheong-gun, Sicheon-myeon, Jungsan-ri, Jungsan-ri Campsite, Mount Jirisan; 35°18.63'N, 127°45.09'E; alt. 700 m; 28 Jul. 2021; J. Kim, C. Lim, D. Lee, W. Lee leg.; sweeping; GenBank: OP081140; CF21-0152; KUEM.

Palpus is 3-segmented. Center of male seventh sternite has a deep conical internal sac that has a wide, round entrance. Outer face of gonostylus has two setae arising from a small tubercle. Paramere is elongated and narrow, distally with a darkened tip.

Male (holotype). Body length 3.5 mm, wing length 4.5 mm, antenna length 0.7 mm. General body coloration yellow (Fig. 3A).

Figure 3. 

Dicranomyia (Erostrata) koreana sp. nov. A habitus, male (holotype) B head, male (paratype) C wing, male (paratype) D male seventh sternite, ventral view E male terminalia, dorsal view F gonostylus, ventral view G aedeagal complex, dorsal view H paramere, lateral view I female terminalia, lateral view J tip of hypovalva, lateral view. Abbreviation: tb – tubercle. Scale bars: 2 mm (A, C); 0.5 mm (B, D, E, I); 0.1 mm (F, G, H, J).

Head (Fig. 3B). Dark brown dorsally, yellow ventrally. Vertex with a distinct black spot between compound eyes. Antennae 14-segmented; scape pale brown; pedicel yellowish brown; flagellum brown. Rostrum pale, reduced. Palpus 3-segmented, yellowish brown; basal 1/2 of first palpomere pale.

Thorax. Prescutum, scutum and scutellum yellow. Mediotergite yellowish brown. Pleuron entirely pale yellow, without lateral stripes. Wing (Fig. 3C) tinged with pale brown; veins brown; tip of Sc reaching ca 1/3 of Rs; sc-r at tip of Sc; R₁ indistinct; R₂ ending distinctly beyond tip of R₁; discal cell closed; m-cu slightly beyond fork of M. Halter pale brown. Legs with coxae and trochanters pale yellow; femora and tibiae brownish yellow; tarsal segments light brown. Femur I 2.4 mm; femur II 2.8 mm; femur III 3.1 mm; tibia I 2.8 mm; tibia II 2.4 mm; tibia III 2.8 mm; tarsus I 2.9 mm; tarsus II 2.5 mm; tarsus III 2.4 mm. Claw without additional tooth.

Abdomen. Tergites yellow except pale eighth tergite; sternites paler. Seventh sternite (Fig. 3D) with central deep, conical, slightly darkened sac, and rounded entrance.

Male terminalia (Fig. 3E–H). Yellow. Ninth tergite rounded (Fig. 3E), wider basally, narrower apically; posterior margin with two short, setose lateral lobes separated by shallow U-shaped incision. Gonocoxite elongated, ventromesal lobe margin rounded and covered with setae, reaching beyond tip of aedeagus. Gonostylus (Fig. 3E, F) widened at base and narrowed at apex, with short, black dorsal spine at tip; dorsal margin near the base with small protuberance bearing two pale setae. Paramere (Fig. 3G, H) with basal part bilobed, distal lobe elongated and narrow, slightly darkened at tip. Aedeagus (Fig. 3G) apically bent downwards, bifid at tip.

Female. Body length 3.8 mm, wing length 4.7 mm, antenna length 0.7 mm (N = 1). General body coloration lighter than male.

Female terminalia (Fig. 3I–J). Yellow. Cercus curved dorsally (Fig. 3I), gradually tapered to pointed tip. Genital fork broad, as long as width, not extending to base of cercus. Hypovalva elongated, blade-shaped reaching slightly before tip of cercus, with distinct dark spot at basal area. Distal end bearing dorsal and ventral serration (Fig. 3J).

Specific name “koreana” refers to the country of its discovery, Korea.

The species is widely distributed in Korea, including Jejudo Island.

This species is found along intermittent mountain streams in moist mixed forests with grassy vegetation (Fig. 4A) and in wet deciduous forest along the rocky margins of small mountain streams (Fig. 4B). Adults share their habitats with D. (E.) globulithorax on Mount Bangtaesan and with D. (E.) tabashii on Mount Jirisan.

Figure 4. 

Habitats of Dicranomyia (Erostrata) koreana sp. nov. A Jejudo Island B Mt. Jirisan.

Adults are mainly active from July through August.

In terms of the shape of the male terminalia, D. (E.) koreana sp. nov. is similar to D. (E.) tabashii, but it can be distinguished by the following characters: palpus 3-segmented (vs 2-segmented); male seventh sternite with weakly darkened, conical internal sac with round entrance (vs strongly darkened, U-shaped internal sac); paramere with darkened tip (vs without). This species is also similar to another species, D. (E.) jejuensis sp. nov. based on the male genital structures, but it can be distinguished by the following characters: male seventh sternite with a deep, conical internal sac (vs shallow, V-shaped notch); gonostylus with two setae from tubercle (vs a single seta); paramere without hook at tip (vs with hook).

The male genitalia of D. (E.) koreana sp. nov. from Mount Bangtaesan differs from other materials of the species based on the shape of the seventh sternite internal sack (shallow conical without rounded mouth) and paramere distal lobe (pointed tip). However, additional specimens are needed to determine whether this difference is due to intra- or interspecific variation.