Copestylum vesicularium

Flower Fly
Copestylum vesicularium

Flower Fly Copestylum vesicularium male on Black-eyed Susan. Jun 29, 2005 Wheatley, Ontario.
Flower Fly Copestylum vesicularium male on Black-eyed Susan. Jun 29, 2005 Wheatley, Ontario.

Identification:
Head: Face reddish-yellow; greatly extended outward at mouth area (like Lejops). Eyes reddish-brown with short thick, yellowish pile. Male eyes touching down entire top of head. Tiny simple eyes (ocelli). Females have wide reddish-yellow area between eyes.
Antenna: Reddish-yellow; 3rd joint very long; bristle (arista) twice as long as 3rd joint, with short feathered hairs.

Flower Fly Copestylum vesicularium male on Dogwood. Jun 08, 2007 Wheatley, Ontario.
Flower Fly Copestylum vesicularium male on Dogwood. Jun 08, 2007 Wheatley, Ontario.

Thorax: Metallic greenish to bluish with black pile. Females may sometimes appear more brownish-green. Segment 1 (scutum) sometimes has base and sides slightly yellowish. About 10 to 12 black bristles along side edges.  Segment 2 (scutellum or half-moon) same colour, sometimes with yellowish pile around edges on the female; also both male and female with black bristles. Thorax sides covered with yellowish-brown pile.
Wings: Clear (hyaline) with a dark spot midway on outer edge (cost). Veins reddish-yellow.Calypters (secondary wings or squamae) are transparent, yellow to orange-red, very thick and unusually large; visible near scutellum.
Legs: Variable, black to reddish-brown with lighter areas, black short hair. Feet usually dark.
Abdomen: Metallic greenish to bluish, base mid area paler to yellow; pile yellowish-white.
Underside has base segments yellow, rest reddish-brown.

Similar Species: Copestylum barei has black pile on abdomen.

Size: 8.5 to 11 mm.

Habitat: Forest edges and meadows.

Food: Adults feed on flowers, sometimes in swarms at dusk on shrubs such as Buttonbush Cephalanthus occidentalis and Dogwoods.

Flight Time: June and July.

Life Cycle: Unknown. Attracted to lights.

Comments: Essex County – photos. Georgian Bay, Pinery at Grand Bend.

Synonyms: Curran 1947
Phalacromya vesicularium, Volucella vesicularia, Volucella vesicularia

References:
United States National Museum, 1886, Vol. 31: Syrphidae by Williston, pg. 141.
American Museum Novitates, 1947, #1361 by Curran, pp. 3 to 6.
Ohio State University, 1953: Syrphidae by Weems, pp. 38, 350 (keys), 353 to 354.
Entomological News, 1963, Vol. 74: Crepuscular flower visits of adult Volucella vesicularia Curran (Diptera, Syrphidae) by Waldbaurer, pp. 135 to 136.

Types:
Holotype as Volucella vesicularia, male by Curran, 1947. Type Locality: New York. In the American Museum of Natural History, New York.

Melanophora roralis

Woodlouse Fly
Melanophora roralis

Woodlouse Flies Melanophora roralis mating on brick wall. Oct. 04, 2017 Leamington, Ontario.
Woodlouse Flies Melanophora roralis mating on brick wall. Oct. 04, 2017 Leamington, Ontario.

Identification: Introduced from Europe
Head: Face black, some white pile below antenna base. Top of head, between eyes silvery gray-back on each side, dull black stripe down center. Eyes not touching on either male or female. Long black hair under mouth area.
Antenna: Black, tiny nubs. Bristle (arista) long, curved and covered with hair.
Thorax: Black, shiny. In certain lights, a slight silvery sheen.

Woodlouse Flies Melanophora roralis mating on brick wall. Oct. 04, 2017 Leamington, Ontario. White tip on wing of female.
Woodlouse Flies Melanophora roralis mating on brick wall. Oct. 04, 2017 Leamington, Ontario. White tip on wing of female.

Wings: Black. Female has large white tip. Cell near to middle of wing is short (Cell M), leaving a long petiole (or line) extending to wing tip (R 4+5). Wings can be a lighter black on newly emerged adults. Calypteres whitish on male, darker on female. Halteres dark.
Legs: Black, feet (tarsi) very long. Very few bristles on legs.
Abdomen: Long, tapered. Last 2 segments bristled, tachinid-like.


Size:
3 to 5.5 mm – size varies according to host.

Habitat: Old forests, damp areas along shorelines.

Food: Unknown, does not visit flowers.

Flight Time: Mid-May to October.

Life Cycle: Females lay eggs on substrates close to sow or pill bugs (Woodlice). Larvae hatch and attach themselves to their host, devouring it. Then pupate inside the pill bug. Pupa are orange, the same size as the host.  Adults have been observed vibrating their wings when walking.

Comments: Essex County – Lake Erie Island.

Synonyms: Linnaeus 1758
Musca roralis Linnaeus, 1758
Musca grossificationis Linnaeus, 1758
Musca interventum Harris, 1780
Musca atra Villers, 1789
Illigeria atra Robineau-Desvoidy, 1830
Illigeria minor Robineau-Desvoidy, 1830
Melanophora atra Robineau-Desvoidy, 1830
Tachina plumigera Wiedemann, 1830
Melanophora distincta Robineau-Desvoidy, 1830
Melanophora festiva Robineau-Desvoidy, 1830
Melanophora violacea Robineau-Desvoidy, 1830
Melanophora nigerrima Macquart, 1834
Melanophora stygia Harris, 1835
Melanophora americana Macquart, 1843
Tachina interlapsa Walker, 1853
Melanophora appendiculata Macquart, 1855
Melanophora brasiliensis Robineau-Desvoidy, 1863
Melanophora nitidiventris Curran, 1928
All synonyms are European, except Curran, 1928 – information not available.

References:
Entomological News, 1903, Vol. 14: A Dexiid Parasite of the Sow-Bug by Brues, pg. 291.
Draft Key to British Calliphoridae and Rhinophoridae, 2016 by Falk, pg. 73.

Types: Unknown

Orthonevra nitida

Flower Fly
Orthonevra nitida

Flower Fly Orthonevra nitida female on Dandelion flower. May 14, 2010, Rondeau Provincial Park, Ontario.
Flower Fly Orthonevra nitida female on Dandelion flower. May 14, 2010, Rondeau Provincial Park, Ontario.

Identification:
Head: Large, as wide at thorax. Main ID: Reddish-brown eyes have a distinct straight line across middle, with squiggly lines throughout the rest of the eye. Face is rough, uneven in profile, dark and sparsely covered with whitish pile on male; eyes touching at top of head before the simple eyes (ocelli). Female face darker, not as much white pile, eyes well separated, dark between.

Flower Fly Orthonevra nitida male on Blackberry leaf. July 31, 2013, Wheatley, Ontario.
Flower Fly Orthonevra nitida male on Blackberry leaf. July 31, 2013, Wheatley, Ontario.

Antenna: Long, as long as head; yellowish-brown, last joint darker. Joints 2 and 3 about equal length.
Thorax: Segment 1 (scutum) light to dark bronze with sparse covering of lighter hair. 4 pile stripes from base to lower margin. Stripes can appear purple, reddish or white, depending on light. Segment 2 (scutellum or half-moon) rough with indented line or groove across segment. Thorax sides sparsely covered with whitish hair.

Flower Fly Orthonevra nitida female on Hoptree flower. June 04, 2007, Wheatley, Ontario.
Flower Fly Orthonevra nitida female on Hoptree flower. June 04, 2007, Wheatley, Ontario.

Wings: Tinted grayish-brown, with darker areas. Veins and cross-veins much darker, patterned.
Legs: Thighs (femora) dark bronze. Shins (tibiae) lighter, with dark streaks. Feet pale yellowish-red, last segment black.
Abdomen: Bronze, not shiny. Last 2 segments have whitish pile.

Flower Fly Orthonevra nitida male on Goldenrod, November 02, 2011, Wheatley, Ontario.
Flower Fly Orthonevra nitida male on Goldenrod, November 02, 2011, Wheatley, Ontario.

Size: 4 to 6 mm.

Habitat: Forests with vernal pools; river, lake and shore edges; ditches.

Food: Adults feed on flower nectar.

Flight Time: June to end of October.

Life Cycle: Most reports from Europe and Georgia, U.S. claim larvae live in wet soil or muck along water sources.  Macquart (France) reports they live in wet tree holes. Larvae about 7 mm long, not including tail. Mating pairs photographed in June, July and October. Perhaps they have 2 generations a year.

Flower Fly Orthonevra nitida mating on Queen Anne's Lace. October 30, 2013. Wheatley, Ontario.
Flower Fly Orthonevra nitida mating on Queen Anne’s Lace. October 30, 2013. Wheatley, Ontario.

Comments: Essex County – Point Pelee, Lake Erie Islands, Ojibway. Kent County – Rondeau Provincial Park. Also Georgian Bay area and Michigan.

Synonyms: Wiedemann 1830
Chrysogaster nitidus, Paragus aeneus, Cryptineura hieroglyphica, Chrysogaster nitida 

References:
List of Dipterous Insects in the collection of the British Museum, 1849, Pt. 3 by Walker, pg. 545.
United States National Museum, 1886, Vol. 31, Syrphidae by Williston, pp. 35 to 36.
Ohio State University, 1953: Thesis Syrphidae by Weems, pp. 310 to 311.

Types:
Holotype as Paragus aeneus female by Walker, 1849. Type Locality: Ohio. In British National Museum of Natural History, London, England.

 

Eristalinus aeneus

Flower Fly
Eristalinus aeneus

Flower Fly Eristalinus aeneus female on Cup Plant. Aug 03, 2010, Wheatley, Ontario.
Flower Fly Eristalinus aeneus female on Cup Plant. Aug 03, 2010, Wheatley, Ontario.

Identification: Introduced from Europe.
Head: Face brownish-white with pale yellowish to white pile. Eyes large, yellowish-brown with pin-hole sized brown dots blending until eyes become brown at top. Male eyes touching just above antenna base. Female eyes not touching, dark brown between eyes above antenna.

Flower Fly Eristalinus aeneus male on Viburnum (Arrowwood), June 11, 2008, Wheatley, Ontario.
Flower Fly Eristalinus aeneus male on Viburnum (Arrowwood), June 11, 2008, Wheatley, Ontario.

 

Antenna: Light brown, sometimes more reddish. Bristle (arista) long.
Thorax: Metallic dark green to brassy. 5 long, whitish pile stripes start at base and continue to mid thorax; obvious on female, faint to absent on male. Thorax sides with some yellowish hair.
Wings: Clear, veins yellowish brown at base, becoming black nearer tips. Halteres brownish-yellow.
Legs: Thighs (femora) brown, tips yellow. Front and middle shin yellow, with yellowish hair, hind shin more brownish. Feet dark, toes yellow.

Flower Fly Eristalinus aeneus female on Ox-eye Daisy, June 01, 2008, Wheatley, Ontario.
Flower Fly Eristalinus aeneus female on Ox-eye Daisy, June 01, 2008, Wheatley, Ontario.

Abdomen: Abdomen shiny, brassy with short yellowish-white hair. Segments may have obscure white pile (visible in certain lights) at base of segments 3 and 4.

Size: 8 to 10 mm.

Habitat: Forests with vernal pools, wet meadows, lake and river shores.

Food: Adults feed on flower nectar.

Flower Fly Eristalinus aeneus male on Aster, Sept 27, 2007, Wheatley, Ontario.
Flower Fly Eristalinus aeneus male on Aster, Sept 27, 2007, Wheatley, Ontario.

Flight Time: April to October.

Life Cycle: Larvae, called rat-tailed, live in vernal pools, fetid water, fresh water and rock pools filled with seaweed. Pupate at bottom of pool in sand in late summer. New adults then hibernate for winter, some apparently using old mud dauber wasps nests, or tunnels of ground nesting bees in protected locations (i.e. under bridges). Reported 6 to 8 in one mud dauber cell (both male and female). One generation per year.

Comments: Essex County – photos. Map by Skevington shows locations along the Great Lakes.

For information on synonyms, references and type specimens see next page

Didea fuscipes

Flower Fly
Didea fuscipes

 

Flower Fly Didea fuscipes male on Ox-eye Sunflower leaf. Sept. 04, 2016, Leamington, Ontario.
Flower Fly Didea fuscipes male on Ox-eye Sunflower leaf. Sept. 04, 2016, Leamington, Ontario.

Identification:
Head: Face yellow; brown spot below antenna, and two spots above antenna. On female, the two brown spots may form an inverted V-shape. Eyes without hair.
Antenna: Black; last joint rounded at tip, base sometimes reddish. Long bristle (arista) reddish.
Thorax: Shiny. Segment 1 (scutum)  greenish-black; each side and along neck (pronotum) covered with thick yellow pile. Segment 2 (scutellum) light yellow, translucent; corners may be darker with some black hairs.

Flower Fly Didea fuscipes male on Ox-eye Sunflower leaf. Sept. 04, 2016, Leamington, Ontario.
Flower Fly Didea fuscipes male on Ox-eye Sunflower leaf. Sept. 04, 2016, Leamington, Ontario.

Wings: Wings clear to grayish tint. Base of wings brownish. Stigma brown.
Legs: Legs brown mixed with yellow.
Abdomen: Black with yellow (to translucent with slight green tint) stripes that do not reach to side edges of abdomen.
Segment 1 has wide yellow, slanted oval stripes starting from outer margin of base slanting in toward center, but not touching.
Segment 2 wide yellow stripe, indented at center, but never broken.
Segment 3 narrower yellow stripe, gradually narrowing to center, but never broken.
Segment 4 small spot at each side edge.

Flower Fly Didea fuscipes male on Ox-eye Sunflower leaf. Sept. 04, 2016, Leamington, Ontario.
Flower Fly Didea fuscipes male on Ox-eye Sunflower leaf. Sept. 04, 2016, Leamington, Ontario.

Similar Species: Didea laxa (alneti) usually has stripes all interrupted at center and touching side edges.

Size: 11 mm.

Larva: 12 to 15 mm.

Habitat: Forests and forest edges, meadows.

Food: Larva often found in colonies of Giant Bark Aphids, like Longistigma caryae, usually in Sycamore and Basswood, but also feeds on several other varieties of aphids.

Flight Time: May to September

Life Cycle: Larva are grubs, without feet or eyes. Brown with 12 bristles across first 2 segments and 12 on last segment; small spines on rest of body. Feed only on juices of mostly Giant Bark Aphids. Frass is dark purple, and helps the larva adhere to bark. Two generations. Second generation of larva only found in September to October. Pupate in mid to late October inside the last instar skin; usually attached to underside of a twig. Overwinters as a pupa.

Comments: Essex County – Lake Erie Islands.

Synonyms: Loew 1863
Didea fasciata of American authors (not Macquart 1834).
Didea pacifica also listed as synonym – doubtful, scutellum described as black.

References:
Buffalo Society of Natural Sciences, 1875-77, Vol. 3: A List N. A. Syrphidae by Osten Sacken, pg. 63.
United States National Museum Bulletin, 1886, #31: Synopsis of N. A. Syrphidae by Williston, pp. 89 to 90.
Ohio Naturalist, 1911, Vol. 11 #7: Preliminary Report on the Life Histories of Two Species of Syrphidae by Metcalf, pp. 337 to 341.
California Academy of Sciences, 1919: 4th Series, Vol. 9 by Lovett, pg. 246.
Note: Doubtful this is a synonym of D. fuscipes due to black scutellum. On D. fuscipes the scutellum is yellow.

Types: Unknown.

 

 

 

Chalcosyrphus chalybeus

Flower Fly
Chalcosyrphus chalybeus

 

Flower Fly Chalcosyrphus chalybeus female on Astilbe. June 07, 2007. Wheatley, Ontario.
Flower Fly Chalcosyrphus chalybeus female on Astilbe. June 07, 2007. Wheatley, Ontario.

Identification:
Head: Face with some white pile. Male eyes meet at top of head before simple eyes (ocelli). Female top of head black between eyes.
Antenna: Black, 3rd joint more brownish, long and wide.
Thorax: Shiny steel blue-black with some short black pile. Shoulders (base outside edges or humeri) lightly dusted with white pile. Thorax side black.

Flower Fly Chalcosyrphus chalybeus female on Viburnum. June 12, 2008. Wheatley, Ontario.
Flower Fly Chalcosyrphus chalybeus female on Viburnum. June 12, 2008. Wheatley, Ontario.

Wings: Metallic steel-blue to black. Inside edge of wings and tip pale purplish.
Legs: Black with short, bristly hair. Hind thigh (femur) much wider.  Hind shin (tibiae) slightly curved.
Abdomen: Metallic steel-blue to black with short black hair.

Size: 12 mm.

Habitat: Forests and swamps.

Flower Fly Chalcosyrphus chalybeus female on Astilbe. June 07, 2007. Wheatley, Ontario.
Flower Fly Chalcosyrphus chalybeus female on Astilbe. June 07, 2007. Wheatley, Ontario.

Food: Adults feed on flower nectar.

Flight Time: June and July

Life Cycle: Unknown. One report of larvae in wet logs of Maple.

Comments: Essex County – Point Pelee, Lake Erie Islands, Ojibway Prairies. Kent County – Rondeau Provincial Park. Georgian Bay area. Also in Michigan.

Synonyms: Wiedemann 1830
Xylota chalybea, Xylota purpurea, Xylotomima chalybea, Xylotomima chalybeus 

References:
List of Specimens of Dipterous Insects in the collection of the British Museum, 1849, Pt. III by Walker, pg. 560.
United States National Museum, 1886, Vol. 31: Syrphidae by Williston, pg. 233.
Ohio State University, 1953: Thesis on Syrphidae by Weems, pg. 382.
Proceedings of the Entomological Society of Washington, 1982, Vol. 84, by Maier, pg. 605.
Journal of the New York Entomological Society, 1988, Vol. 96, by Thompson, pg. 222.

Types:
Holotype as Xylota purpurea by Walker 1849. Type Locality: U.S. In the British Museum of Natural History, London, England.

 

Blera badia

Flower Fly
Blera badia

 

Flower Fly Blera badia female. Berwick, Nova Scotia, June 4, 2011.
Flower Fly Blera badia female. Berwick, Nova Scotia, June 4, 2011.

Identification:
Head: Face white, top of head with long white hair on female. Male eyes touching, no hair. Eyes reddish-brown. Dark stripe down middle below antenna base.
Antenna: Base black, last segment light brown, large, rounded.
Thorax: Entirely brassy-brown covered with pale yellowish hair, including thorax sides.

Flower Fly Blera badia female. Berwick, Nova Scotia, June 4, 2011.
Flower Fly Blera badia female. Berwick, Nova Scotia, June 4, 2011.

Wings: Clear, veins brown, yellowish at base. Halteres yellow. Calypters whitish with yellowish fringe.
Legs: Thighs (femora) black, hind one yellow with extensive black tip. Shins (tibiae) yellow with black tips. All covered with short yellowish hair. Feet yellow, last segment black. Toes yellow.

 

 

Abdomen: Mostly black, with short white hair along side edges. Segment 2 has yellow triangle at each side, pointing to center. Segment 3 has some yellow on side edge, wider at base of segment, larger on female.
Underside yellow, except segment 4 wide black at center.

Flower Fly Blera badia female. Berwick, Nova Scotia, June 4, 2011.
Flower Fly Blera badia female. Berwick, Nova Scotia, June 4, 2011.

Size: 9 to 11 mm.

Habitat: Forests.

Flight Time: May to June

Life Cycle: Unknown. Most larvae of this genus live in decaying wood or under bark, some use wet treeholes.

Comments: Kent County – Rondeau Provincial Park. Georgian Bay area.

Synonyms: Walker 1849
Xylota badia, Eristalis intersistens, Criorhina intersistens, Cynorhina badia

References:
List of the Specimens of Dipterous Insects in the collection of the British Museum, 1849, Pt. III by Walker, pp. 559, 615 to 616.
United States National Museum, 1886, Vol. 31: Synopsis of N.A. Syrphidae by Williston, pp. 212 to 213.
Entomological News, 1913, Vol. 24: On Criorhina intersistens by Johnson, pp. 293 to 294.
Ohio State University, 1953: Thesis: Syrphidae by Weems. pp. 408 to 409.
University of Kansas Science Bulletin, 1924, Vol. 15, by Curran, pp. 133 to 134.

Types: Unknown

 

Blera analis

Orange-tipped Flower Fly
Blera analis

Flower Fly Blera analis male on Astilbe. June 06, 2007, Wheatley, Ontario.
Flower Fly Blera analis male on Astilbe. June 06, 2007, Wheatley, Ontario.

Identification:
Head: Face light orangish-yellow with light dusting of white pile. Face much projecting and shiny at antenna base. Eyes reddish-brown. Male eyes touching at top of head, female eyes separated by simple eyes (ocelli). Black spot below lower eye margin (cheeks).
Antenna: Orangish-yellow, like face. 1st and 2nd joints with some black pile. 3rd joint large, rounded. Bristle (arista) reddish-black.
Thorax: Entirely metallic greenish-black, covered with whitish pile. Pile denser along shoulders (base, outside edge or humeri). Sides have tufts of dense, short white hair.

Flower Fly Blera analis male on Astilbe. June 06, 2007, Wheatley, Ontario.
Flower Fly Blera analis male on Astilbe. June 06, 2007, Wheatley, Ontario.

Wings: Lightly tinted, more yellowish-brown at base. Some veins very dark. Calypters white, with fringe. Halteres very pale yellow.
Legs: Thighs (femora) black, tips light yellow. Shins (tibiae) brownish, densely covered with white pile; base and tips more yellowish-orange; hind shin more yellowish. Feet light yellow, last joint black. Toes yellow.
Abdomen: Shiny black with black pile. Segment 2 has longer, white hair at side edges. Segment 4 is yellow-orange, with black V-shape at base, center on male; female has a larger black U-shape (more rounded). Segment 5 entirely yellow-orange.

Size: 9 to 12 mm long.

Habitat: Forests.

Food: Adults feed on flower nectar.

Flight Time: Mid May to early July. June 12, 2004

Life Cycle: Unknown. In England, the larvae live in water-filled tree holes.

Comments: Rare. Essex County – photos. Recorded around Georgian Bay and in Thedford. Also in Michigan.

Synonyms: Macquart 1842
Milesia analis, Cynorhina analis, Criorhina analis

References:
United States National Museum, 1886, Vol. 31: Synopsis of N.A. Syrphidae by Williston, pg. 214.
University of Kansas Science Bulletin, 1924, Vol. 15: Syrphidae by Curran, pg. 135.
Ohio State University, 1953: Thesis Syrphid Flies by Weems: pp. 410 to 412.

Types: Unknown

Toxomerus politus

Flower Fly
Toxomerus politus

Flower Fly Toxomerus politus female Aug 17, 2016. Leamington, Ontario.
Flower Fly Toxomerus politus female Aug 17, 2016. Leamington, Ontario.

Identification:
Head: Face yellow below antenna. Above antenna solid white on male; two white stripes up inner eye margin on female, light brownish between stripes. Eyes red, hind margins curved at center, covered with white hair.
Antenna: Yellow, slight reddish tint on female.
Thorax: Metallic blackish-bronze. Segment 1 (scutum) has obvious white pile stripe down center; outside edges of segment bordered with a yellow stripe. Segment 2 (scutellum or half-moon) yellow, may be partly covered with brownish pile. Thorax sides dark brown with series of oblong and round yellow spots. Another small yellow spot above front leg.

Flower Fly Toxomerus politus male on Little Bluestem Schizachyrium scoparium, Sep 08, 2007, Wheatley, Ontario.
Flower Fly Toxomerus politus male on Little Bluestem Schizachyrium scoparium, Sep 08, 2007, Wheatley, Ontario.

Wings: Wings very slightly tinted yellowish. Darker yellowish along outside edge (costa), sometimes appears whitish. Stigma brownish-yellow. Halteres yellow.

Legs: Pale yellowish. Hind feet more reddish-yellow; last foot segment brown.

 

 

Flower Fly Toxomerus politus female, Aug 22, 2015, Leamington, Ontario.
Flower Fly Toxomerus politus female, Aug 22, 2015, Leamington, Ontario.

Abdomen: Black with yellow to orangish stripes; stripes ‘bleed’ or coalescence.
Segment 1: Wide yellow stripe across segment.
Segment 2 & 3: Narrow yellow stripe across base of segment. Wide stripe below it. Longitudinal yellow line down center. On male, lower stripe widens each side of center and is interrupted, exposing the complete longitudinal center stripe. Female sometimes has segment 3 wide stripe interrupted at center, like the male.

Flower Fly Toxomerus politus male on Goldenrod, Sep 07, 2004, Wheatley, Ontario.
Flower Fly Toxomerus politus male on Goldenrod, Sep 07, 2004, Wheatley, Ontario.

Segment 4: Stripe on base may be narrow or wide, depending on age, and sometimes becomes whitish. A black T-shaped line below the base stripe, not reaching side edges. Rest of segment yellow, V-shaped.
Segment 5: Entirely yellow.
Underside yellow.

Size: 7 to 9 mm long.

Habitat: Meadows with tall grasses, farm fields with corn.

Flower Fly Toxomerus politus male on Big Bluestem Andropogon. Aug 17, 2016, Leamington, Ontario.
Flower Fly Toxomerus politus male on Big Bluestem Andropogon. Aug 17, 2016, Leamington, Ontario.

Food: Adults and larvae feed on grass and some flower pollen, like goldenrod.

Flight Time: July to September.

Life Cycle: Females lay eggs in flowers of tall grasses like Sorghum species, Big Bluestem Andropogon and Maiden Grass Miscanthus sinensis and corn. Larvae feed on pollen from these flowers and pupate in the flower or seed heads. T. politus is the only Toxomerus that does not feed on aphids.

Comments: Essex County – Point Pelee. Extends to Toronto area.

For information on synonyms, references and type specimens see next page

Toxomerus marginatus

Flower Fly
Toxomerus marginatus

Flower Fly Toxomerus marginatus female on Coreopsis. Jun 18-05 Wheatley, Ontario.
Flower Fly Toxomerus marginatus female on Coreopsis. Jun 18-05 Wheatley, Ontario.

Identification:
Head: Face yellow. Female has yellow stripe along inner eye margin, dark between stripes above antenna. Red eyes with hind margin indented and covered with yellowish hair.
Antenna: Yellow to reddish-yellow. Bristle (arista) long, black.
Thorax: Segment 1 (scutum) blackish-bronze with yellow stripe down each side and a yellowish pile stripe down the center. Segment 2 (scutellum or half-moon) can be yellow or sometimes partly covered with black pile. Thorax side dark with series of 3 yellow spots from wing base to front leg.

Flower Fly Toxomerus marginatus male on Fleabane. Stripes bleeding or joining together. Jun 21, 2007, Wheatley, Ontario.
Flower Fly Toxomerus marginatus male on Fleabane. Stripes bleeding or joining together. Jun 21, 2007, Wheatley, Ontario.

Wings: Clear, veins dark except for base and outer wing edge (costa) yellowish-orange. Halteres yellowish.
Legs: Pale yellow, dark stripe down hind shin (tibiae); feet brown.
Abdomen: Black with yellow to orange marks. Marks or pattern sometimes ‘bleed’ or coalescence.
Segment 1: Yellow to orange mark across center of segment, may be interrupted at center. Does not touch side edges.

Flower Fly Toxomerus marginatus female. Abdomen stripes orange May 07, 2007, Wheatley, Ontario.
Flower Fly Toxomerus marginatus female. Abdomen stripes orange May 07, 2007, Wheatley, Ontario.

Segments 2 and 3: Wide yellow to orange stripe, covers well over half the length of the segment, broken at center by a yellow-orange longitudinal line. Stripe does not touch side edges.
Segment 4: Yellow-orange oblong spot each side of center leaving a small dark stripe at center.
Tip black. Underside yellow to orange, the side edges usually visible from the top.

Flower Fly Toxomerus marginatus collecting on thistle. July 07, 2013. Wheatley, Ontario.
Flower Fly Toxomerus marginatus collecting on thistle. July 07, 2013. Wheatley, Ontario.

Similar Species: Toxomerus geminatus stripes on abdomen segments 2 and 3 are less than half the segment length, extend to side edges and are lobed.

Size: 5 to 6 mm.

Habitat: Meadows, forest edges, urban and farm areas

Food: Adults eat nectar and pollen from flowers.

Flower Fly Toxomerus marginatus female. Abdomen stripes bleeding or joining together. June 30, 2005, Wheatley, Ontario.
Flower Fly Toxomerus marginatus female. Abdomen stripes bleeding or joining together. June 30, 2005, Wheatley, Ontario.

Flight Time: May to October.

Life Cycle: Females lay eggs on plants with aphids. Larva consume the aphids and pupate in the soil. Many generations per year.

Comments: Essex County – Point Pelee National Park, Lake Erie Islands, Ojibway Prairies. Kent County – Rondeau Provincial park. Widespread in Ontario.

For information on synonyms, references and type specimens see next page