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Species Drasteria petricola - Little Arches - Hodges#8631

Drasteria petricola Moth from western SD - Drasteria petricola Moth help - Drasteria petricola Moth help - Drasteria petricola lepidoptera - Drasteria petricola
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 Erebidae
Subfamily Erebinae
Tribe Melipotini
Genus Drasteria
Species petricola (Little Arches - Hodges#8631)
Hodges Number
Synonyms and other taxonomic changes
Drasteria petricola (Walker, 1858)
Euclidia petricola Walker, 1858
* phylogenetic sequence #930905
Forewing length 12-14 mm. (1)
The smallest of the Arches (Drasteria) moths. In Alberta, it is the only species in the genus with black lines along the veins of the ventral forewing margin. The mountain populations (ssp. athabasca) tend to be slightly larger and have a more yellow-tan cast to the hindwing compared to the prairie populations (ssp. crokeri). Prairie individuals can be strikingly different with their blue-grey and white colouration, and Barnes and Benjamin (1924) thought these differences may be indicative of a separate species; Individuals from the Calgary and Lethbridge region seem to be intermediate between the two forms, but more work is needed to clarify this situation.
A western species, found from the Yukon and NWT south to New Mexico in the Rockies, east to Manitoba (Lafontaine & Wood, 1997).
Sparsely vegetated, open habitats, including alpine and montane meadows and prairie grasslands.
Adult flight peaks between mid May and mid July, earlier at lower elevations.
The larvae feed on Hedysarum (Lafontaine & Wood, 1997). Adults take nectar at flowers, including mint in Utah (Richards, 1939).
Life Cycle
Adults are diurnal and do not come to light. They can be difficult to detect and observe with their rapid flight and contrasting black and white coloration.
Print References
Powell, J.A. & P.A. Opler 2009. Moths of Western North America. University of California Press. pl.44.13f, p.258 (1)
Internet References
Moth Photographers Group - species page
E.H. Strickland Museum - species page
CBIF - image of pinned adult
Works Cited
1.Moths of Western North America
Powell and Opler. 2009. UC Press.