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.

 

Leave a Reply