Spodoptera praefica
Grote, 1875
Western Yellow-striped Armyworm, Western Yellow-striped Armyworm Moth
Spodoptera praefica, the western -striped , is a to western North America. The has two periods annually, occurring in early spring and late summer. are black with yellow stripes and feed on herbaceous plants including several agricultural . The species is considered a high risk for invasion into the European and Mediterranean region but is currently absent from that area.



Pronunciation
How to pronounce Spodoptera praefica: /spoʊˈdɒptərə priˈfɪkə/
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Identification
distinguished from the similar by paler lacking the blurry stripe, and by that are white or gray with a small dot on the surface. recognized by the black body with stripes and inverted "Y" marking on the .
Images
Habitat
Associated with in agricultural and natural settings. feed on leaves of various herbaceous plants.
Distribution
to western North America: from British Columbia to California, east to Utah, and north to Alberta. Absent from the EPPO (European and Mediterranean Protection Organization) area as of October 2021.
Seasonality
active March–April and August–September. Two distinct periods annually.
Diet
feed on leaves of herbaceous plants including agricultural : alfalfa, potato, rice, sugar beet, and sweet potato.
Host Associations
- alfalfa - larval agricultural
- potato - larval agricultural
- rice - larval agricultural
- sugar beet - larval agricultural
- sweet potato - larval agricultural
Life Cycle
with , , , and stages. Larvae are the feeding and damaging stage. Two annually corresponding to the bimodal adult periods.
Behavior
attracted to ultraviolet light sources. feed externally on foliage.
Ecological Role
; larval stage functions as a folivore on herbaceous plants. Potential agricultural pest.
Human Relevance
Agricultural pest of several . Considered a high risk for invasion into Europe and the Mediterranean region, with potential to become established as a pest in that area. Subject to by protection organizations.
Similar Taxa
- Spodoptera ornithogalliSimilar appearance, but S. ornithogalli has darker with a blurry stripe and different pattern.
- Spodoptera exiguaBoth are Spodoptera with larval stages that can be pests of agricultural , but S. exigua are typically green above and pinkish or yellowish below with a stripe.
More Details
Invasion Risk
As of 4 October 2021, the is absent from the EPPO area but considered a high risk for invasion there.
Blacklight Attraction
have been documented visiting blacklighting displays in California, indicating activity and attraction to UV light sources.
Sources and further reading
- BugGuide
- Wikipedia
- GBIF taxonomy match
- iNaturalist taxon
- NCBI Taxonomy
- Catalogue of Life
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