﻿Japanese species of Ormosia Rondani (Diptera, Limoniidae): revision of the subgenera Oreophila Lackschewitz and Parormosia Alexander

﻿Abstract Japanese species of the subgenera Oreophila Lackschewitz and Parormosia Alexander of the genus Ormosia Rondani (Limoniidae) are revised. Two new species Ormosia (Oreophila) komazawai Kato & Kolcsár, sp. nov. and Ormosia (Parormosia) phalara Kato & Kolcsár, sp. nov. are described. The identities of all Japanese species of the two subgenera are clarified and redescribed with images of habitus and wings, and drawings of male and female terminalia. The first DNA barcode sequences of the species Ormosia (Parormosia) diversipes Alexander and Ormosia (Parormosia) phalara Kato & Kolcsár, sp. nov. are also provided. A key to, and distribution maps of, the Japanese species are provided.


Introduction
Ormosia Rondani (1856) is a relatively large genus of the subfamily Chioneinae (family Limoniidae) and includes 224 species worldwide (Oosterbroek 2022). Twelve fossil species of the genus have been described from the Baltic amber (Podėnas 1999  Diagnosis. General coloration yellow to pale brown (Fig. 1A). Vertex often pale brownish grey. Antenna dark brown except scape. Wing yellowish tinged, unpatterned. Legs distal to mid-tibiae gradually becoming dark brown towards tips. Male terminalia: tergite 9 bearing pair of triangular lobes at caudal margin. Gonocoxite slightly produced beyond base of clasper of gonostylus. Clasper of gonostylus wider apically, 3/4 length of lobe of gonostylus, distal part 2× as wide as that of lobe of gonostylus. Interbases fused medially into roundish sac-like plate, without mesalapical lobe. Female terminalia with cercus almost straight, slightly upcurved on distal part. Genital frame with lateral arm of genital fork roughly triangular, situated at posterior 1/3 of genital fork, with finger-shaped lobe on posterior end. Sternite 9 very small, fan-shaped.
Redescription. Male. Body length 2.9-4.2 mm, wing length 4.1-5.9 mm. Head: covered with yellow to brown setae. Vertex dusky yellow to pale brownish grey, paler grey on anterior part, often widely dark brown on center of posterior part. Eyes small and widely separated, ~ 1/2 as wide as narrowest point of vertex, ~ 1/3 length of head including rostrum in dorsal view. Rostrum dusky yellow to pale brown, ~ 1/2 length of eye in lateral view. Palpus 5-segmented, 2/3 length of head, dusky yellow on basal two segments, dark brown on succeeding segments, palpomere 1 small, globular, palpomere 2 cylindrical, palpomeres 3-5 globular. Labellum dark brown. Antenna 15 to 16-segmented, relatively short, ~ 2× length of head; scape dusky yellow to pale brown, 2× as long as wide; pedicel dark brown, oval, 2/3 length of scape; flagellomeres dark brown, barrel-shaped, gradually decreasing in size toward apical segment; each flagellomere with ca. six verticils, longest one except in apical segment ~ 1.5× as long as each segment.
Male terminalia (Fig. 7): Tergite 9 with pair of small triangular lobe at caudal margin, less than 1/4 length of middle of tergite 9; anterior margin of tergite 9 deeply and widely notched; tergite 9 slightly wider than long including caudal lobe (Fig. 7A). Sternite 9 largely membranous on posteromedial part (Fig. 7B), anteromedial part convex ventrally in lateral view. Gonocoxite gradually narrowing towards tip, slightly longer than tergite 9, posteroventral margin distinctly and roundly produced beyond base of clasper of gonostylus, produced part ~ 1/2 length of clasper of gonostylus (Fig. 7A). Gonocoxal apodeme short, connected to anterolateral part of interbase (Fig. 7D). Clasper of gonostylus dark and scabrous, slightly shorter than lobe of gonostylus, almost same width in whole length, rounded at tip, weakly curved dorsally on distal part, ca. as wide as lobe of gonostylus in apical view (Fig. 7C). Lobe of gonostylus long finger-shaped, slightly curved, ~ 1/2 length of gonocoxite, distal part flattened (Fig. 7C). Interbases fused medially into roundish sac-like plate, ca. as long as wide in dorsal view, posterior margin almost straight or slightly concave, anterolateral part with short arm (Fig. 7D). Paramere roughly blade-shaped, ca. as long as interbase (Fig. 7D, E). Aedeagus dorsoventrally flattened, ~ 1/3 width of sac-like interbase or slightly wider, weakly constricted near middle in dorsal view, tip slightly beyond apex of interbase ( Female. Unknown. Etymology. This spectacular and unique species is named in honor of its collector, Masaki Komazawa. Habitat and biology. Masaki Komazawa observed specimens walking on the surface of fallen leaves or on the surface of soil just after snow melt (Fig. 6A).
Remarks. The subapterous male of this species is unique in the subgenus, but brachypterous female is known in a Nearctic species, Ormosia (Oreophila) parviala Petersen & Gelhaus, 2004(Petersen et al. 2004). This species is similar to Ormosia (Oreophila) confluenta in terms of body coloration, Ormosia (Oreophila) longicornis Savchenko, 1980(Savchenko 1980 from Kazakhstan in terms of long antenna reaching (almost) apex of abdomen if bent backward, and Ormosia (Oreophila) bergrothi (Strobl, 1895) in terms of structure of male terminalia.  Diagnosis. General coloration brownish black (Fig. 8A). Vertex often brownish grey. Antenna dark brown. Wing blackish tinged, stigmal region weakly dark. Halter yellow at base and knob. Legs entirely brownish black. Male terminalia: tergite 9 bearing of three small triangular lobes at caudal margin. Gonocoxite slightly produced beyond base of clasper of gonostylus. Clasper of gonostylus divided into two long arms, dorsal arm almost straight, strongly narrow and bent outward at tip, ventral arm slightly longer than dorsal arm, apical part strongly widened and rounded. Interbase with mesal-apical lobe long blade-shaped, curved at extreme tip, basal part of each in-terbase fused with each other. Female terminalia with cercus stout, strongly upcurved. Hypogynial valve rounded at tip. Genital frame with lateral arm of genital fork roundish, situated at posterior end of genital fork. Sternite 9 slender, arched bridge-shaped.
Remarks. This species is similar to a Chinese species, Ormosia (Oreophila) subducalis Alexander, 1940(Alexander 1940b, but is differentiated from it by the following characters: wing entirely blackish tinged (brownish yellow with clearer yellow base in Ormosia (Oreophila) subducalis); halter dark brown, base and knob yellow (orange yellow in Ormosia (Oreophila) subducalis).
Abdomen: dark brown, densely covered with yellow setae. Male terminalia (Fig. 14): Tergite 9 with pair of long and flat, largely membranous lobes at caudal margin, ~ 1/3 length of remainder of tergite 9; tergite 9 slightly longer than wide including caudal lobe (Fig. 14A). Sternite 9 slightly and widely convex at posterior margin (Fig. 14B). Gonocoxite roundish, slightly shorter than tergite 9, posteroventral margin not produced beyond base of clasper of gonostylus. Gonocoxal apodeme long, connected to each other, forming bridge, central part jointed with anteromedial part of interbase (Fig. 14D). Clasper of gonostylus dark, slightly longer than gonocoxite, divided into two arms; dorsal arm short, stout and curved ventrally, rounded at tip, distal 1/2 densely covered with black microscopic setae; ventral arm ~ 2× as long as dorsal arm, blade-shaped, weakly twisted, gradually narrow toward tip, acute at tip (Fig. 14C). Lobe of gonostylus slender, narrower, and slightly shorter than clasper, weakly dilated at apical 1/4, with several long setae on ventral margin near tip, obtuse at tip (Fig. 14C). Interbase Thorax: covered with yellow setae, rarely brownish. Pronotum brown to dark brown, often yellowish on lateral side of postpronotum. Mesonotum brown to dark greyish brown, sometimes lighter brown around prescutal pit. Prescutal pit brown to black, oval to long bacilliform, often widened toward outer end. Tuberculate pit distinct, situated at anterior 2/5 between anterior margin of mesonotum and prescutal pit. Pleuron subnitidous, dark brown. Wing (Fig. 13) relatively wide, 3.1-3.2× as long as wide; tinged with brown, sometimes weakly yellowish on prearcular region, stigmal region weakly dark; Sc ending at level of R 2 or slightly distal to it; crossvein sc-r distinct, situated between levels of basal 1/3-1/2 of Rs; R 2+3+4 1/7-1/3 length of R 3 ; R 2 situated between fork of R 2+3+4 and length of itself distal to it; M 4 1-2× as long as M 3+4 ; cell dm closed, 0.4-0.7× as long as cell m 1+2 , or sometimes open by atrophy of crossvein m-m; wing margin between tips of CuP and A 1 2.5-3× as long as that between tips of CuP and CuA; A 1 curved posteriorly near middle. Halter dusky yellow, ~ 3/5 length of thorax (Fig. 12A). Legs with coxae to femora dark brown, femora very narrowly pale at bases; tibiae to tarsi yellow to dusky yellow, tips of tibiae and distal segments of tarsi weakly dark (Fig. 12A).
Female. Body length 3.6-5.0 mm, wing length 4.2-5.9 mm. Generally resembling male (Fig. 12B), except antenna shorter, ~ 2× as long as head; flagellomeres often dark brown entirely, with ca. eight verticils on each of basal segments, fewer on each of distal segments, longest one at most 1.5× as long as each segment. Tibiae to tarsi dark brown, concolorous with femora (Fig. 12B).
Remarks. This species resembles a Chinese species, Ormosia (Parormosia) nigripennis Alexander, 1936(Alexander 1936a, but this species has two-spined mesalapical lobe of the interbase (Fig. 14D, E), while the latter species has a single pointed lobe on the interbase.  Diagnosis. General coloration brown to dark brown (Fig. 8B). Vertex greyish. Antenna brown to dark brown. Mesonotum subnitidous. Wing brownish tinged, stigmal region barely dark. Cell dm open. Halter dusky yellow. Legs mostly dark brown, yellowish on trochanters and bases of femora. Male terminalia: tergite 9 bearing pair of large triangular lobes at caudal margin. Clasper of gonostylus divided into two arms; ventral arm ~ 1.5× as long as curved stout dorsal arm, roughly blade-shaped, wide at middle and narrow on distal part. Lobe of gonostylus flattened, slightly shorter than clasper, gradually widened distally, widest part ~ 1/3 length of lobe of gonostylus, pointed at apicodorsal corner, distal margin with several long setae. Interbases fused medially into large roundish plate, pointed at tip, mesal-apical lobe absent. Female terminalia with cercus relatively slender, upcurved distally. Lateral arm of genital fork pointed and curved posteriorly. Sternite 9 subacute at posterior end.
Thorax: covered with yellow setae. Pronotum dark brown, yellowish on postpronotum. Mesonotum subnitidous, brown to dark brown, with small yellowish area just above lateral end of postpronotum. Prescutal pit dark brown, oval to long bacilliform.
Female terminalia (Fig. 18): dark brown, cercus amber-color. Tergites 8 and 9 fused. Cercus relatively slender, upcurved distally, 1.3× longer than tergite 10; hypogynial valve 1.8× as long as sternite 8, gradually narrowed toward tip, basal part 1.3× as wide as that of cercus, tip ending at level of basal 2/3 of cercus (Fig. 18A). Genital frame with genital fork gradually widened toward anterior and posterior ends, narrowest at anterior 1/4, lateral margin of posterior end produced into small lobe; lateral arm of genital fork pointed at tip and curved posteriorly, situated at posterior end of genital fork; sternite 9 relatively long, subacute at tip; one large membranous area present posterior to genital opening (Fig. 18B). Three spermathecal ducts present (Fig. 18B). Spermathecae indistinct. Distribution. Japan (Honshu) (Fig. 5D) and Russia (FE). Remarks. This species is similar to a Nearctic species, Ormosia (Parormosia) divergens (Coquillett, 1905) (Coquillett 1905), but is differentiated from it by the following characters: clasper of gonostylus without lobe at fork into dorsal and ventral arms ( Diagnosis. General coloration dark brown (Fig. 19). Vertex greyish. Antenna yellowish on pedicel and at least basal segments of flagellum. Mesonotum with ochreous to greyish brown parts. Wing dark brownish tinged, patterned with subhyaline spots on veins, spots free from veins absent. Cell dm closed. Halter yellow. Legs dark brown with narrow yellow areas at tips of femora and bases of tibiae in female, tibiae to tarsi mostly yellow in male. Male terminalia: tergite 9 bearing pair of long membranous lobes at caudal margin. Clasper of gonostylus divided into two arms, ventral arm ~ 3× as long as curved stout dorsal arm, slender blade-shaped, gradually narrow toward tip. Lobe of gonostylus slender and 3/5 length of clasper, tapered distally, with long setae on ventral margin at distal 2/5. Interbase with mesal-apical lobe bearing two claws. Female terminalia with cercus slender, weakly upcurved distally. Lateral arm of genital fork rounded. Sternite 9 rounded posteriorly.
Description. Male. Body length 3.2-3.6 mm, wing length 4.2-4.7 mm. Head: covered with yellow and black setae. Vertex grey to dark grey, dark brownish on posterolateral part. Eyes relatively large and widely separated, ~ 4/5 as wide as narrowest point of vertex, ~ 1/2 length of head including rostrum in dorsal view. Rostrum dark brown, ~ 1/2 length of eye in lateral view. Palpus dark brown, 5-segmented, ca. as long as head, palpomere 1 globular and small, palpomeres 2-5 cylindrical, slenderer in palpomeres 2 and 5. Labellum dark brown. Antenna 3× as long as head; 16-segmented, scape dark brown, 2× as long as wide, narrower basally; pedicel pale to dusky yellow, roughly globular, 1/2 of length of scape; flagellomeres pale to dusky yellow, sometimes weakly dark on distal segments, oval on basal one or two segments, long cylindrical on distal segments, each flagellomere with one or two verticils, longest one at most 2× as long as corresponding segment, gradually shorter toward distal segment, sensilla abundant especially in ventral side, at most 1/2 as long as each flagellomere.
Thorax: covered with yellow to dark brown setae. Antepronotum dark brown, pale at caudal margin; postpronotum dusky yellow. Mesonotum ochreous to greyish brown, dark brown at anterior and lateral margins, sometimes with three indistinctly dark stripes just anterior to transverse suture. Prescutal pit dark brown, roughly oval with narrower inner end. Tuberculate pit distinct, situated at anterior 1/3 to 1/2 between anterior margin of mesonotum and prescutal pit. Pleuron dark brown, variegated with grey pruinosity (Fig. 19A). Wing (Fig. 20) tinged with dark brown, subhyaline on prearcular region, patterned with subhyaline spots restricted to vicinity of veins, without ones free from veins; spot each at MA, Rs origin, crossvein sc-r, outer end of cell dm, and tips of all longitudinal veins; spot at each tip of R 1 , and R 4 to CuA smaller; cord seamed with subhyaline; relatively narrow, 3.3× as long as wide; Sc ending at level of R 2 ; crossvein sc-r distinct, situated at level of middle of Rs; R 2+3+4 2/7 length of R 3 ; R 2 situated between 1/2-1× lengths of itself distal to fork of R 2+3+4 ; M 4 0.6-0.7× as long as M 3+4 ; cell dm closed, 0.7-0.8× as long as cell m 1+2 ; wing margin between tips of CuP and A 1 2.5-3× as long as that between tips of CuP and CuA; A 1 curved posteriorly near middle. Halter white to dusky yellow, slightly brownish at base, ~ 1/2 length of thorax (Fig. 19). Legs with coxae dark brown; trochanters dusky yellow on fore pair, brown to dark brown on mid and hind pairs; femora dark brown, bases and tips narrowly yellow; tibiae yellow, tips weakly brownish; tarsi yellow, turning to brown to dark brown toward tip distal to middle of tarsomere 1 (Fig. 19A). Abdomen: dark brown, densely covered with brown setae; yellowish setae present on genital part.
Female. Body length 3.6-4.8 mm, wing length 4.2-5.0 mm. Generally resembling male (Fig. 19B)   with ca. eight verticils on each of basal segments, fewer on each of distal segments, longest one at most 1.5× as long as corresponding segment. Tibiae to tarsi dark brown, bases of tibiae narrowly yellow (Fig. 19B). Female terminalia (Fig. 22): dark brown, cercus and hypogynial valve amber-colored, weakly dark on basal parts. Tergites 8 and 9 fused. Cercus weakly upcurved distally, 1.6× longer than tergite 10; hypogynial valve relatively stout, 1.5× as long as sternite 8, gradually narrowed toward tip, basal part 1.4× as wide as that of cercus, tip ending at level of basal 3/5 of cercus (Fig. 22A). Genital frame with genital fork widened posteriorly, anterior part slender; lateral arm of genital fork weakly produced, rounded, situated at posterior of genital fork; sternite 9 rounded posteriorly; long and arched groove present posterior to genital opening, lateral part curved anteriorly (Fig. 22B). Three spermathecal ducts present, basal parts blackened (Fig. 22B). Spermathecae indistinct. Etymology. The name of this species, phalara, is from the Greek phalaros, meaning white-spotted. The name is deemed to be a Latinized feminine adjective in nominative singular.
Remarks. This species resembles a Chinese species, Ormosia (Parormosia) angustaurata Alexander, 1936(Alexander 1936b, but is distinguished from it by the following characters: scape dark brown (yellow in Ormosia (Parormosia) angustaurata); wing with subhyaline spots restricted to vicinity of veins, without smaller spots free from veins (with at least a few smaller spots free from veins in addition to ones on veins in Ormosia (Parormosia) angustaurata); mesal-apical lobe slender with additional spine near tip (Fig. 21D, E) (stout and without additional spine in Ormosia (Parormosia) angustaurata).
Natural Science of Drexel University, Philadelphia, USA) for helping examine specimens in USNM and Floyd Shockley and Torsten Dikow (USNM) for allowing us to examine their specimens. We are grateful to Jaroslav Starý and to Sigitas Podėnas for reviewing the manuscript. This study was supported by the International Research Fellow of the Japan Society for the Promotion of Science (JSPS) Grant Numbers: P21094 to L.-P. Kolcsár and the Ministry of Education, Culture, Sports, Science and Technology, Japan (MEXT) to a project on Joint Usage/Research Center, Leading Academia in Marine and Environment Pollution Research (LaMer).