Tachydromia maculipennis Walker, 1849

Shamshev, Igor V. & Grootaert, Patrick, 2024, Revision of the described Nearctic species of the genus Tachydromia Meigen (Diptera: Hybotidae), Zootaxa 5403 (2), pp. 151-196 : 172-175

Tachydromia maculipennis Walker

( Fig. 10 )

Tachydromia maculipennis Walker, 1849: 507 . Type locality: Canada, St. Martin’s Falls, Albany River, Hudson’s Bay (after Smith 1971: 367).

Tachypeza pusilla Loew, 1864b: 87 [Cent. 5, no. 74]. Type locality: USA, Illinois .

Tachydromia pusilla (Loew) : Melander, 1910: 52 (synonymy).

Phoneutisca bimaculata Loew : Melander, 1902: 204. Misidentification.

Type material examined. Smith (1971: 367) provided data about the holotype of this species, which is represented only by two legs. Data on the syntype of Tachypeza pusilla Loew (including photos of labels and habitus) are available from the database of insect primary types in the collection of MCZ (https://mczbase.mcz.harvard.edu/ guid/ MCZ:Ent:1168) .

Additional material examined. CANADA. Manitoba: Aweme, 14.vi.1924, R.D. Bird (2 ♂, 2 ♀, CNC); 2 mi. W Stockton, 26.v.1958, C.D.F. Miller (1 ♂, CNC); 5 mi. SW Chilo, ex choke-cherry, floodplain community nr. Tamarack Bog, 5.vi.1958, J.F. McAlpine (1 ♂, 7 ♀, CNC); 2 mi. W Stockton, ex flowers Erysimum aspersum , 26.v.1958, J.F. McAlpine (1 ♂, 1 ♀, CNC); Ninette, ex. Amelanchier blossoms, 16.v.1958, J.F. McAlpine (1 ♀, CNC). Ontario: Hog’s Back, 9.vi.1923, R. Ozborn (1 ♀, CNC); Chatham, 18333.D, 28.v.1928, A.B. Baired (1 ♀, CNC); same locality, 18333.D, 1.vi.1928, A.B. Baired (1 ♂, CNC); Simcoe, 29.v.1939, G.E. Shewell (1 ♂, 6 ♀, CNC); same locality, 2.vi.1939, G.E. Shewell (1 ♀, CNC); same locality, 3.vi.1939, G.E. Shewell (2 ♂, 4 ♀, CNC); same locality, 5.vi.1939, G.E. Shewell (2 ♂, 2 ♀, CNC); same locality, 9.vi.1939, G.E. Shewell (1 ♀, CNC); same locality, host Spiraea , 18.vi.1939, G.E. Shewell (3 ♀, CNC); Ottawa, 1.vi.1939, O. Peck (1 ♀, CNC); Manotick, taken from Malaise trap, 27.v.1952 (3 ♂, 9 ♀, CNC); Marmora, Hawthorn, 29.v.1952, G.E. Shewell (1 ♂, CNC); Manotick, Malaise trap, vi.1952, J.F. McAlpine (2 ♂, CNC); Maynooth, host Spiraea , 18.vi.1953, J.F. McAlpine (9 ♂, 10 ♀, CNC); Ottawa, 31.v.1954, J. R. Vockeroth (1 ♂, CNC); Midland, 20.5.1959, J.G. Chillcott (1 ♀, CNC); Petawawa, 28.v.1959, J. R. Vockeroth (1 ♂, CNC); Ottawa, 8.vi.1959, hand-written name unclear (1 ♂, CNC); Osgoode, 22.v.1964, J. R. Vockeroth (1 ♀, CNC). Quebec: Lanoraie, 21.vi.1915, G. Beaulieu (1 ♀, CNC); Aylmer, 28.v.1923, C.H. Curran (1 ♂, CNC); Aylmer, 28.v.1923, C.H. Curran (1 ♂, CNC); Hull, 27.v.1923, C.H. Curran (4 ♂, 14 ♀, CNC); Hull, 4.vi.1923, C.H. Curran (1 ♂, CNC); Hemmingford, 13.vi.1930, J.B. Maltais, Tachydromia maculipennis Walk. ( bimaculata Lw. ) (1 ♀, CNC); Abbotsford, 22.v.1936, G. Shewell (1 ♂, 1 ♀, CNC); Abbotsford, 4.vi.1936, G. Shewell (2 ♂, 3 ♀, CNC); Abbotsford, 1.vi.1937, G. Shewell (1 ♀, CNC); Abbotsford, 1.vi.1937, G. Shewell (1 ♂, CNC); Old Chelsea, on flowers of Prunus pensylvanica , 16.v.1958, J. R. Vockeroth (2 ♀, CNC); Kingsmere, 16.v.1959, J.G. Chillcott (1 ♂, CNC); Breckenridge, 31.v.1959, C.H. Mann (1 ♂, CNC); Old Chelsea, Summit King Mt., 1150’, 22.vi.1961, J. R. Vockeroth (1 ♀, CNC); Mt. Orford, 1200’, 5.vi.1963 [no collector name] (1 ♀, CNC). Saskatchewan: Beat, ex. Euphorbia esula ; Jamson, 30.v.1977, G. Thomas // Tachydromia maculipennis Walk. , det. H.J. Teskey, 1978 (1 ♀, CNC). USA. Alaska: Circle, 25.vi.1948, S. Lienk, AlaskaIns Project (1 ♂, USNM). Colorado: Builder, Flagstaff Canyon, 5800’, on side of stream, 10.vi.1961, C.H. Mann (2 ♂, CNC). Connecticut: Redding, 14.v.1938, A.L. Melander (17 ♂, 10 ♀, USNM). Illinois: Macoupin Co., Carlinville, 4.6.1888, C.A. Robertson // Charles Robertson Collection, 7699 (1 ♀, INHS); Champaign Co., Urbana, 19.v.1892, J. Marten (1 ♂, INHS); Algonquin, 2.vi.1894 (1 ♀, INHS); same locality, 23.v.1895 (2 ♀, INHS); same locality, 22.v.1895 (1 ♀, INHS); same locality, 3.v.1896 (1 ♀, INHS); same locality, 8.v.1896 (6 ♀, INHS); same locality, 10.v.1896 (1 ♀, INHS); Macoupin Co., Carlinville, 18.v.1898, C.A. Robertson // Charles Robertson Collection, 20921 (1 ♀, INHS); Algonquin, 24.v.1908, Mason [1 ♀ with label Tachydromia pusilla Loew, Coquillett ] (6 ♂, 11 ♀, INHS); same locality, 6.vi.1908, Mason (1 ♀, INHS); Havana, Gleason’s sand dune, 30.iv.1914 (1 ♂, INHS); St. Joseph, Salt Fork, 3.v.1914 (3 ♂, 1 ♀, INHS); same locality, 10.v.1914 (1 ♂, 2 ♀, INHS); same locality, 17.v.1914 (1 ♂, 3 ♀, INHS); Urbana, on flowers of Spiraea , 14.v.1914 (3 ♂, 7 ♀, INHS); Urbana, Fair Grounds, 20.v.1914 (1 ♀, INHS); Planeview, 3.v.1915 (1 ♀, INHS); Urbana, on flowers of dogwood, 23.v.1916 (2 ♀, INHS); Savanna, 14.vi.1917 (1 ♀, INHS); Meredosia, 28.v.1917 (2 ♀, INHS); same locality, 30.v.1917 (1 ♀, INHS); Dubois, 22.v.1917 (1 ♀, INHS); Alto Pass, 7.v.1917 (1 ♀, INHS); Muncie, Stony Cr., 10.v.1924 (1 ♀, INHS); Shawneetown, 28–29.iv.1926, coll. Auden & Frison (1 ♀, INHS); Antioch, on Prunus virginiana , 3.vi.1943, Ross & Sanderson (1 ♀, INHS); Baker, Indian Ck., 4.vi.1943, H.H. Ross & M.W. Sanderson (1 ♀, INHS); Elburn, Ill., on Prunus , 19.v.1944, Ross & Sanderson (3 ♂, 4 ♀, INHS); Halfday, 19.v.1944, Ross & Sanderson (1 ♂, INHS); Champaign Co., Ent. Class, 9.v.1965 (9 ♂, 13 ♀, INHS). Kansas: Pottawatomie, Co., 29.iv.1929, R.H. Painter (1 ♂, 1 ♀, USNM); Nat. Hist. Res. Lawrence, 26–28.v.1956, J.G. Chillcott (1 ♂, 1 ♀, CNC). Maryland: Beltsville, 13.v.1917, W.L. McAtee (1 ♀, USNM). Michigan: E. Lansing, 19.v.1936, C. Sabrosky // Tachydromia maculipennis Walk. (1 ♂, USNM); Lapeer Co, 30–31.v.1937, C. Sabrosky (4 ♀, USNM); E. Lansing, 3.vi.1937, C. Sabrosky (1 ♀, USNM); Lake Co., 20.v.1939, R. R. Dreisbach (2 ♀, CNC); Midland Co., 1.vi.1939, R. R. Dreisbach (1 ♀, CNC); same locality, 31.v.1944, R. R. Dreisbach (1 ♀, CNC); same locality, 21.v.1944, R. R. Dreisbach (1 ♀, CNC); same locality, 27.v.1951, R. R. Dreisbach (1 ♂, CNC); Saginaw Co., 20.v.1953, R. R. Dreisbach (1 ♀, CNC). New York: Ithaca, 5.v.1913 (1 ♂, USNM); same locality, 7.v.1913 (1 ♂, USNM). North Dakota: Burleugh Co., Long Lake, 4.vi.1969, W.W. Wirth (1 ♂, USNM). Ohio: Four-Mile Cr., nr. Oxford, 26.v.1979, B.A, Steinly (1 ♀, USNM). Pennsylvania: Rauchtown, Clinton Co., on blossoms of Fragaria sp. , 15.v.1964, J.G. Chillcott (1 ♂, 1 ♀, CNC).

Recognition. A small, robust species distinguished by the following combination of characters: proepisternum shiny; fore femur broadly brown ringed, yellow at apex and near base; wings mostly faintly infuscate, darker in cells r 1 and r 2+3, halter with dark knob.

Redescription. Male ( Fig. 10A ). Length: body 1.6–1.8 mm, wing 1.5–1.7 mm. Head black. Occiput almost entirely shiny, only with patch of fine pruinosity above neck; 2 long, black vertical setae; some black setae around neck, with finer pale setae near mouth-opening; row of pale minute postoculars. Ocellar triangle shiny; ocellars short, lateroclinate. Frons shiny, slightly broadened towards ocellar tubercle, above antennae nearly 3.0 times as broad as anterior ocellus. Antenna brown. Postpedicel subglobular; stylus subapical, short, nearly 1.5 times as long as pedicel and postpedicel combined. Proboscis brown. Palpus unmodified, elongate oval, short (shorter than proboscis), brownish; clothed in scattered yellowish and brownish setulae, with 1 short (somewhat shorter than palpus) black subapical seta.

Thorax black,largely shiny; prosternum,lower margin of notopleural depression,scutellum,meron(except middle part) and postnotum light grey tomentose. Postpronotal lobe large, slightly elongate oval, lacking conspicuous setae, with scattered minute setulae. Mesonotum with 1 black, long (posteriorly) and 1 short notopleurals, 1 moderately long postalar and 4–6 scutellars (cruciate apicals nearly as long as posterior notopleural seta, laterals shorter); some minute setulae present behind postpronotal lobe and on notopleural depression anteriorly; acrostichals lacking; dorsocentrals uniserial, scattered, mostly minute, 1 prescutellar pair somewhat longer (considerably shorter than postalar seta).

Leg colour: coxae and trochanters entirely yellow; fore femur yellow apically and broader near base (broadly dark brown ringed), mid and hind femora yellow on extreme base; fore tibia yellowish closer to base; fore and mid tarsomeres 1–3 yellowish (more distinctly on fore tarsus), hind basitarsus mostly yellowish; otherwise legs dark brown. Coxae clothed in numerous pale to yellowish setae; fore coxa subshiny anteriorly. Fore femur strongly thickened, pubescent ventrally, with short, pale anteroventral and posteroventral setulae becoming longer closer to base. Fore tibiae spindle-shaped, with unmodified setation. Mid femur only slightly narrower than fore femur; shallow ventral excavation on basal half, bearing rows of short, black anteroventral and posteroventral spinule-like setae (latter somewhat stronger). Mid tibia with very small apical projection, bearing weakly prominent ventral spinule-like setulae. Hind femur nearly as broad as mid femur, unmodified, lacking prominent setae. Hind tibia and tarsus unmodified.

Wing normally developed, rounded at apex, with unmodified venation; large faintly brownish infuscate, slightly paler closer to base but decidedly darker on cells r 1 and r 2+3. One very short, basal costal seta. Vein R 2+3 straight. Veins R 4+5 and M 1 parallel throughout. Vein M 4 distinct throughout. Crossveins r-m and bm-m broadly separated. Cell r 1 nearly as broad as cells r 2+3 and r 4+5. Calypter brownish, with scattered fringe. Halter with yellow stem and dark knob.

Abdomen brownish; tergites faintly pruinose anteriorly and shiny posteriorly; sternites entirely shiny, mostly with scattered dark setulae; sternite 8 with long posteromarginal setae.

Hypopygium ( Fig. 10B–D ) brown, large, rather subglobular. Right epandrial lamella ( Fig. 10C ) rather subglobular viewed laterally, bearing numerous long setae; without ventral projection. Right surstylus not separated from epandrial lamella, short, elongate oval (lateral view); bearing short setae. Left epandrial lamella ( Fig. 10D ) small, with some short setae apically. Left surstylus barely separated from epandrial lobe; rather large, elongate oval, with excavation dorsally; covered with short setae. Cerci ( Fig. 10B ) separated, with some unmodified moderately long to short setae; right cercus very short, subtriangular (dorsal view); left cercus rather subrectangular, narrow, much longer than right cercus. Hypoproct with apical portion slender, digitiform, slightly produced beyond apex of left cercus.

Female. Fore femur largely yellowish with indistinct brownish yellow markings apically (varying in size and intensity), tarsi entirely brownish. Fore femur lacking basal excavation. Fore tibia lacking apical projection. Otherwise as in male. Cercus brownish, long, slender, with minute setulae.

Remarks. Tachydromia maculipennis belongs to the T. connexa group sensu Chvála (1970), although this species has shiny proepisternum. The structure of the male genitalia suggests that T. maculipennis is most similar to a complex of the species allied in the Palaearctic to T. halterata (Collin) . In the Nearctic, this complex includes T. maculipennis , T. monacha Melander and T. magadanica Shamshev (also two undescribed species). Tachydromia maculipennis is one of a few Nearctic species of the genus exhibiting a very broad, almost transcontinental distribution in North America.

Distribution. Canada (Manitoba, Ontario, Quebec, Saskatchewan), USA (Alaska, Colorado, Connecticut, Illinois, Kansas, Maryland, Michigan, New York, North Dakota, Ohio, Pennsylvania).

Figures

FIGURE 10. Tachydromia maculipennis Walker, male (Canada, Ontario; CNC). A. Habitus, lateral view. B. Hypopygium, dorsal view. C. Right epandrial lamella and right surstylus, lateral view. D. Left epandrial lamella and left surstylus, lateral view. Abbreviations: cerc—cercus; epand—epandrium; hypd—hypandrium; lft sur—left surstylus; rt sur—right surstylus. B–D: scale bar is 0.1 mm.