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Species Petrophila bifascialis - Two-banded Petrophila - Hodges#4774

Moth? - Petrophila bifascialis Two-banded Petrophila  - Petrophila bifascialis Petrophila bifascialis Petrophila bifascialis Two-banded Petrophila, #4774 - Petrophila bifascialis Two-banded Petrophila - Petrophila bifascialis Petrophila bifascialis Two-banded Petrophila - Hodges#4774 - Petrophila bifascialis
Show images of: caterpillars · adults · both
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Lepidoptera (Butterflies and Moths)
Superfamily Pyraloidea (Pyralid and Crambid Snout Moths)
Family Crambidae (Crambid Snout Moths)
Subfamily Acentropinae
Tribe Argyractini
Genus Petrophila
Species bifascialis (Two-banded Petrophila - Hodges#4774)
Hodges Number
Synonyms and other taxonomic changes
original combination Cataclysta bifascialis Robinson, 1869 (description)
* phylogenetic sequence # 143975
Explanation of Names
BIFASCIALIS: from "bi" (two) + "fascia" (band, bundle); refers to the bands across the median area of both wings, and is the origin of the suggested common name above
wingspan 11-24 mm (1)
TL ≈ 7-12mm (2)
forewing whitish with broad brownish-orange band across median area, and 3 smaller bands at varying angles near apex; hindwing white with broad orange band bordered distally (and sometimes proximally) by grayish band in median area, , and a line of large black spots along outer margin. See Heppner's description(3)
Peppery white FW with double brown median band and three angled dashes at apex. HW has row of black and silver spots along outer margin (2)
eastern North America: Nova Scotia to Florida, west to Texas, north to Ontario
larvae are aquatic, living in silken webs in fast-flowing streams
adults rest on nearby vegetation during the day, become active at night, and are attracted to light
adults fly from late May to September
larvae feed on diatoms and algae scraped from rocks in fast-flowing streams (1) (and Illinois Dept. of Natural Resources)
I have found this marking the most helpful - on the hind-wing "an oblong black discal spot"
See Also
Petrophila fulicalis has 3 dark spots arranged in triangle on forewing (lacking in P. bifascialis)
Petrophila canadensis hindwing has dark speckling near apex, and a white space between two reddish bands in median area
Internet References
pinned adult image by John Glaser, plus flight season and distribution (Larry Line, Maryland)
pinned adult image and photos of related species by Jim Vargo (Moth Photographers Group)
presence in Texas; list (Dale Clark, Texas)
presence in Florida; list (John Heppner, Florida State Collection of Arthropods)
presence in Ontario; list (NHIC; Ontario Ministry of Natural Resources)
Works Cited
1.Field Guide to Moths of Eastern North America
Charles V. Covell, Jr. 2005.
2.Peterson Field Guide to Moths of Northeastern North America
David Beadle and Seabrooke Leckie. 2012. Houghton Mifflin.
3.Synopsis of the genus Parargyracytis (Lepidoptera: Pyralydae: Nymphulinae) in Florida
John B. Heppner. 1976. The Florida Entomologist, volume 59, number 1.