Friday, July 10, 2009

Wasp Mimic Flower Fly (Spilomyia alcimus)

Wasp Mimic Flower Fly
(Spilomyia alcimus)

Range: Wisconsin to Newfoundland, and south to Mississippi and Florida. (1)

Size: 15-18 mm ... around 5/8". (1)

Habitat: Open areas with flowers near forests. (2)

Food: Adults take pollen and/or nectar from various flowers. (2)

Identification: Yellow pigment pattern on eyes ... "V" mark on thorax (scutum, in front of scutellum) ... short antennae. (Short antennae are almost always the quickest way to know you are observing a fly and not a wasp.) (2)

Remarks: A very convincing wasp mimic: The yellow pattern on the eyes of S. alcimus helps disguise its "fly eyes". Observers report this species often rests on its four posterior legs and waves it black front legs mimicking the antennae movement of a wasp. (2)

Comments: This specimen was photographed "feeding" on the outside of a plastic watering can. There was no water on the outside of the can, but there was a dried residue of fish emulsion. I assume this attracted the fly to the watering jug.

 Sources and additional information:

(1) BugGuide Species Page
(2) BugGuide Genus Page.
(3) Field Guide to the Flower Flies of Ontario (Pinned images with identification characteristics.)




Mobugs said...

Another great image Marvin. Isn't Mother Nature grand. I am constantly amazed at the diversity of the creatures around us.

Anonymous said...

Great shot there mate, love it.

SAPhotographs (Joan) said...

This is a magnificent bug Marvin and you have done a stunning job photographing it. Excellent info too. Thanks for sharing.