Identification, Images, & Information
For Insects, Spiders & Their Kin
For the United States & Canada

Species Euxoa silens - Silent Dart - Hodges#10751

Silent Dart - Euxoa silens Euxoa silens
Show images of: caterpillars · adults · both
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Lepidoptera (Butterflies and Moths)
Superfamily Noctuoidea (Owlet Moths and kin)
Family Noctuidae (Owlet Moths)
Subfamily Noctuinae (Cutworm or Dart Moths)
Tribe Noctuini
Subtribe Agrotina
Genus Euxoa
No Taxon (Subgenus Euxoa)
Species silens (Silent Dart - Hodges#10751)
Hodges Number
Synonyms and other taxonomic changes
described in 1875 by Grote, who originally placed it in genus Agrotis
Explanation of Names
silens: a Latin word derived from "silere" (to be silent); this is the origin of the suggested common name Silent Dart but I don't know what it refers to
wingspan 37-41 mm
Adult: forewing light grayish-brown with paler costa; usually has thin black basal streak expanding into poorly defined dark median streak incorporating claviform spot and running through orbicular and reniform spots; orbicular spot small, oval; reniform spot kidney-shaped; both spots filled with contrasting pale scales except for lower part of reniform; transverse lines missing; darker shading extends short distance outward from top and bottom of reniform spot - but not from middle of reniform spot; series of small sagitate (arrowhead-shaped) dashes between veins near outer margin; hindwing white with smoky brown scales along outer end of veins and along outer margin, more extensive in females; a rare gray unstreaked form also occurs
[adapted from description at U. of Alberta]
British Columbia and Alberta to California and Arizona, east to Colorado; the type specimen was collected in Nevada
dry grasslands; adults are nocturnal and come to light
adults fly from late April to July in California
See Also
Euxoa clausa forewing has larger and more oblong orbicular spot, lower end of reniform spot not filled with dark scales, and species is restricted to northern great plains (doesn't occur in southwestern states)
E. costata, castanea, idahoensis forewing costal strip is noticeably paler in basal half, and PM line is distinct (see photos of these and other species by Jim Vargo at MPG)
E. laetificans flies later (August to October: 1, 2) and forewing has solid black shading immediately beyond reniform spot (see images at CBIF)
E. unica forewing has distinct AM & PM lines, and pairs of dark markings along the costa; E. furtivus forewing has pale streaks in subterminal area, and a blackish terminal band (compare images of all three species at CBIF)
Internet References
pinned adult image by G.G. Anweiler, plus habitat, description, distribution (Strickland Entomological Museum, U. of Alberta)
pinned adult image plus photos of related species by Jim Vargo (Moth Photographers Group)
presence in Utah; list (Joel Johnson, Utah Lepidopterists Society)
presence in California; list of 14 specimen records with dates and locations (U. of California at Berkeley)