Rhamphomyia (Pararhamphomyia) diversipennis Becker

Sinclair, Bradley J., Vajda, Élodie A., Saigusa, Toyohei, Shamshev, Igor V. & Wheeler, Terry A., 2019, Rhamphomyia Meigen of the Canadian Arctic Archipelago, Greenland and Iceland (Diptera: Empididae), Zootaxa 4670 (1), pp. 1-94 : 32-36

Rhamphomyia (Pararhamphomyia) diversipennis Becker

( Figs 19–21 , 62B, C )

urn:lsid:zoobank.org:act:199A8094-8B4A-45CD-8453-30ACBF0297A8

Rhamphomyia diversipennis Becker, 1900: 19 . Type-locality: “Kantaika” [=Khantayka, a river, 68°06′N 86°33′E, Krasnoyars- kiy Territory, Russia] (by lectotype designation). Other references: Melander, 1928: 191 (catalogue); Shamshev, 2001: 327 (key).

Rhamphomyia (Pararhamphomyia) diversipennis Becker : Frey, 1922: 43 (key); Frey, 1955a: 477 (revision); Chvála & Wagner, 1989: 299 (catalogue); Yang et al., 2007: 170 (catalogue); Shamshev, 2016: 63 (checklist).

Note on synonymy. Becker (1900) listed three males and one female in his type series of R. diversipennis . The location of the fourth and male syntype is unknown (probably Berlin).

Type material examined. LECTOTYPE (here designated in order to fix identity of species) ♂ ( Fig. 19A ), labelled ( Fig. 19B ): “Kantiaka” [=Khantayka, Krasnoyarskiy Territory, Russia]; “ J. Sahlb. ”; “123”; “Rhamphomya [sic!]/ diversipennis Beck. ”; “Spec. typ.”; “Mus. Zool. H:fors/ Spec. typ. No. 4036./ Rhamphomyia / diversipennis Beck. ”; “ LECTOTYPE / Rhamphomyia diversipennis / Becker/ des. Sinclair & Saigusa 2018 [red label]” ( MZH) . PARALECTOTYPES: Russia: Krasnoyarskiy Territory: Dudinka, J. Sahlberg (1 ♀, MZH); Dudinka, Wuoren- taus (1 ♂, MZH) .

Additional material examined. CANADA. Manitoba: Eastern creek nr. Churchill , 25.vi.–9.vii.1952, J.G. Chillcott (21 ♂, 10 ♀, CNC); Churchill, 2–30.vii.1952, J.G. Chillcott (2 ♂, 4 ♀, CNC); same, 8.vii.1952, C.D. Bird (1 ♀, CNC); Churchill, 31.vii.1974, C. Sabrosky (1 ♂, USNM) . Northwest Territories: Kidluit Bay, N. Richards Is. W, 25–29.vii.1948, J. R. Vockeroth (1 ♂, 2 ♀, CNC); Tuktoyaktuk , 15.vii.1971, D.M. Wood (2 ♂, CNC); Tuk- toyaktuk, 69°26′40.02″N 133°1′55.74″W, sweeping meadow, 14.vii.2010, Goulet & Boudreault (4 ♂, 1 ♀, CNC); Tuktoyaktuk, 69°26′16.20″N 133°1′2.16″W, pan trap, meadow, 15–18.vii.2010, Goulet & Boudreault (9 ♂, 1 ♀,

CNC). Nunavut: nr Beechey Lk., 65°14′N 106°50′W, 7.vii.1966, G.E. Shewell (1 ♂, CNC); Chesterfield, 19.vii.– 8.viii.1950, J. R. Vockeroth (26 ♂, 16 ♀, CNC); Coral Harbour, 15–16.viii.1959, W. R.M. Mason (2 ♂, 2 ♀, CNC); Coral Harbour, Southampton Is., 11–26.vii.1948, G.E. Shewell (3 ♂, 4 ♀, CNC); Dubawnt Lk., 63°18′N, 101°37′W, 2.viii.1966, J.G. Chillcott (2 ♂, 1 ♀, CNC); Eskimo Point, 18–28.vii.1950, G.G. DiLabio (69 ♂, 19 ♀, CNC); same, 18–24.vii.1950, G. R. Roberts (1 ♂, 1 ♀, CNC); Fraser Lk., 68°45′N, 120°36′W, 19.vii.1969, G.E. Shewell (1 ♂, CNC); Kugluktuk, 67.77639°, -115.30882°, Repl.3, wet, MT, 7–12.vii.2010, NBP field party (5 ♂, LEM); Kug- luktuk, 67.77639°, -115.30882°, Repl.3, wet, MT, 10.vii.2010, NBP field party, CCDB-21421-E09 (1 ♀, barcoded, LEM). Yukon: British Mtns, Firth River, 14–30.vii.1956, R.E. Leech (10 ♂, 3 ♀, CNC); British Mtns, Firth River, 25–31.vii.1956, E.F. Cashman (5 ♀, CNC). USA. Alaska: Kivalina R., 68°16′N 163°27′W, 10–17.vii.1974, K.W. Philip (5 ♂, CNC); Kotzebue, 18.vi.1951, R.I. Sailor (1 f3, USNM); Nome, Bourbon Ck, bog, 21.vi.1994, T. Sai- gusa (1 ♂, KUMF); Teller, 10.vii.1951, R.I. Sailor (1 ♂, USNM); Umiat, 10.vii.1959, J.E.H. Martin (2 ♂, CNC); Umiat, 8–14.vii.1959, R. Madge (1 ♂, 3 ♀, CNC); Unalakleet, 3–28.vi.1961, B.S. Heming (19 ♂, 7 ♀, CNC).

Diagnosis. This dark-legged and dark setose species is readily recognized from all other species of Pararhamphomyia by the modified wing venation in both sexes, four shiny, dorsal scutal vittae and shiny femora. In males, crossvein dm-m is absent and in females cell bm is greatly elongated with apex almost reaching the wing margin, cell dm is open (m-m and dm-m absent) and vein M 2 is reduced.

Redescription. Wing length 3.8–4.5 mm. Male. Head dark in ground-colour, with grey pruinescence on face, frons, postgena and occiput. Holoptic, eye with ommatidia larger on upper half, smaller on lower half. Frons represented by very small triangular space below ocellar tubercle and larger subtriangular space above antennae, bare; face slightly divergent towards mouthparts, bare, with oral margin dark and shiny. Ocellar triangle with grey pruinescence, with pair of long, dark anterior ocellar setae; 1 pair of posterior ocellar setae (sometimes absent) slightly more than 0.5X length of anterior pair. Occiput bearing row of postocular setae; upper section with long curved setae overlapping eye; lower section with finer setae, not overlapping eye; occipital setae shorter and stronger than postocular setae; setae on postgena hair-like, dark. Antenna dark, densely pruinose. Scape 2X longer than pedicel; pedicel bulbous; postpedicel about 5X longer than basal width; stylus as long as scape. Palpus grey, densely pubescent, with fine dark setulae. Clypeus pruinescent; labrum lustrous and dark reddish-brown, slightly longer than eye height; labellum grey, with dark setae.

Thorax dark in ground-colour, largely grey pruinescent. Scutum with pair of distinct lustrous, dark vittae between acr and dc rows, separated by broad grey pruinose band; pair of dark, lustrous patches between dc and spal. Pleura grey pruinescent, with brownish shadows on sclerites. Proepisternum with several short and some longer, fine, dark setae on lower section; upper section in front of spiracle bare; prosternum bare. Antepronotum with row of short, stout, dark setae. Postpronotum with several short, dark, stout setae and 2 longer, stouter, dark setae. Scutum with biserial fine acr increasing in length posteriorly, ending before prescutellar depression, slightly shorter than dc; 9–10 dc uniserial, longer and stouter than acr, increasing in length and stoutness posteriorly, anterior seta offset laterally; 1 presut spal (= posthumeral) and several finer setae; 3–4 long npl with 3–4 fine, short setae anteriorly; 2–3 prealar setae; 2–4 psut spal; 1 long pal and 2–3 shorter, finer, dark setae; 1 pair of long, stout, apical sctl and 1 pair of shorter lateral sctl. Laterotergite with several fine, dark setae of different lengths. Anterior and posterior spiracles pale with outer black ring.

Legs mostly dark reddish-brown, femora shiny, coxae with grey pruinescence. Hind and mid coxae with lateral row of dark, short, stout setae, with several scattered finer setae; fore coxa with row of dark, stout, short setae and several scattered finer setae anteriorly. Femora with ventral whitish pilosity, longer on hind leg. Fore and hind femora ( Fig. 20B ) with 1 anteroventral and 1 posteroventral row of fine, long setae, not longer than width of corresponding femur. Mid femur with 1 anteroventral and 1 posteroventral row of strong setae, some longer than width of femur. Fore tibia with row of fine, pale posteroventral setae; long fine setae posteriorly; 1 subapical anterodorsal and 1 posterodorsal seta stout, dark, longer than tibial width. Mid tibia with 1 preapical and 1 proximal anterodorsal seta, as long as 2X tibial width ( Fig. 20A ); ventrally with stout anteroventral and posteroventral rows of setae, dark, spine-like. Hind tibia with anteroventral and posterodorsal setae as long as 2X tibial width; anteroventral and posteroventral setae subequal to width of tibia, slender ( Fig. 20B ); 1 long seta in posteroapical comb. Fore tarsomere 1 similar in width to foreleg, with several stout anteroventral and posteroventral setae; long fine setae posteriorly, 2X tarsal width. Mid tarsomere 1 with row of stout anteroventral and posteroventral setae, some longer than tarsal width. Hind tarsomere 1 somewhat thickened, broader than other tarsomeres, with anterodorsal and posterodorsal setae generally longer than tarsal width; ventrally with rows of stout anteroventral and posteroventral setae; circlet of subapical setae, ventral setae stouter.

Wing lightly infuscate; basal costal seta absent; pterostigma present as darkened area. CuA+CuP weak, fading out before wing margin; R 4+5 slightly sinuous; crossvein dm-m absent ( Fig. 62C ). Anal lobe well-developed; axillary incision at right angles. Halter yellowish.

Abdomen dark similar to thoracic ground-colour, with grey pruinescence, slightly thinner on tergites; segment margins pale. Margins of tergites 2–4 lined with long, dark, stout setae; setae on remaining segments finer and slightly shorter; setae on sternites longer on apical segments. Marginal setae on sternite 8 shorter than length of sternite. Tergite 8 one-third length of sternite 8.

Terminalia ( Fig. 20C ) compact with epandrium shiny; epandrium as large as abdominal width, outer margin pronounced and flattened, bearing many dark, long setae; posterior apical corner digitiform, directed inwards and bearing short, dark, spine-like setae. Cercus upright, black, pruinescent on upper half, short and apex bearing many short, fine setae; in dorsal view cercus with triangular lobe directed medially on anterior third and subapical triangular lobe. Subepandrial lobe slender, projecting beyond epandrium, bearing several short setae along inner margin; apex with several long, fine setae. Hypandrium stout, tubular, hidden within epandrium; tip swollen, characterized by dentate projections along dorsal margin, and tip pointed and curved anteriorly; some dentate projections along anterior margin; phallus enclosed within hypandrial tube, emerging as digitiform process below complex apex of hypandrium; phallus folded back on itself subapically, with simple single fold, opposing surfaces tightly appressed. Ejaculatory apodeme about as large as cercus, with lateral wings along ventral margin forming acute angle with apodeme.

Female. Similar to male except wing ( Fig. 62B ) slightly more narrowed cell bm greatly elongated with apex almost reaching wing margin, forming veins thickened, cell dm open (crossveins m-m and dm-m absent) and vein M 2 reduced (sometimes present as short portion before wing margin); M 4 short, thick, arched to wing margin; hind femur with ventral pile on apical half only.

Distribution. This western-central southern arctic species ( Danks 1981, figs 62, 63) is newly recorded from the low arctic in the Nearctic Region ( Fig. 21 ) and is recorded also from eastern Siberia, Russia ( Shamshev 2016).

Figures

FIGURE 19. Rhamphomyia (Pararhamphomyia) diversipennis Becker. A. Lectotype, lateral view; B. Type labels.

FIGURE 20. Rhamphomyia (Pararhamphomyia) diversipennis Becker. A. Male midleg, anterior view; B. Male hindleg, anterior view; C. Male terminalia, lateral view.

FIGURE 21. Known distribution of Rhamphomyia (Pararhamphomyia) diversipennis Becker in North America.

FIGURE 62. Wings of arctic Rhamphomyia. A. R. albopilosa, female, dorsal view; B. R. diversipennis, female, ventral view; C. R. diversipennis, male, ventral view; D. R. hilariformis, female, ventral view.