Spilomyia foxleei
Vockeroth, 1958
Foxlee's Hornet Fly
Spilomyia foxleei is a of syrphid fly (hover fly) in the Syrphidae, first described by Vockeroth in 1958. It belongs to a renowned for its striking mimicry of yellowjacket , employing visual, behavioral, and acoustic deception. The species occurs in western North America, with documented records in British Columbia, Canada, and the Pacific states of the United States.
Pronunciation
How to pronounce Spilomyia foxleei: /ˌspaɪloʊˈmaɪə ˈfɒksˌliːaɪ/
These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.
Identification
Members of the Spilomyia can be distinguished from yellowjacket by their short with a terminal (versus long, thick wasp antennae), large that meet or nearly meet at the top of the , and a single pair of wings (Diptera) versus two pairs in Hymenoptera. Spilomyia further obscure boundaries with black and yellow markings, wave their front legs to simulate wasp antennae, and possess darkened wing regions that mimic the longitudinal wing fold of resting yellowjackets. Specific characters distinguishing S. foxleei from are not documented in available sources.
Distribution
Canada: British Columbia; United States: California, Oregon, Washington.
Behavior
Spilomyia exhibit sophisticated mimicry, including: waving front legs to simulate wasp ; wingbeat frequencies nearly identical to yellowjacket models, producing similar acoustic signatures; and resting postures that mimic folded wasp wings. These function as defensive adaptations against .
Ecological Role
syrphid flies visit flowers and contribute to pollination. Larvae of Spilomyia inhabit water-filled tree holes and feed on decaying organic matter, serving as decomposers and nutrient cyclers.
Similar Taxa
- Dolichovespula arenaria (Aerial Yellowjacket)Visual model for Spilomyia mimicry; distinguished by two pairs of wings, long thick , and longitudinal wing folding at rest.
- Vespula pensylvanica (Western Yellowjacket)Visual and acoustic model for Spilomyia mimicry; distinguished by two pairs of wings, long thick , and longitudinal wing folding at rest.
- Spilomyia longicornis with similar -mimicking appearance; specific distinguishing characters for S. foxleei not documented.
More Details
Taxonomic History
Described by John R. Vockeroth in 1958. The specific epithet honors Foxlee, presumably a collector or contributor to the .
Specimen Rarity
As of available data, iNaturalist records show 35 observations, suggesting the is infrequently encountered or underreported relative to more common Spilomyia species.