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Genus Petrophila

Two-banded Petrophila, #4774 - Petrophila bifascialis

Moth to UV Light 3 - Petrophila fulicalis

Two Banded Petrophila (Petrophila bifascialis) - Petrophila

Show images of: caterpillars · adults · both

Classification

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

Synonyms and other taxonomic changes

Petrophila Guilding, 1830

synonym Cataclysta Hübner, 1825

synonym Parargyractis Lange, 1956

Numbers

17 species in North America

Size

wingspan 11-24 mm

Identification

Adult: often holds forewings partly open at rest, revealing row of silver-patched black spots along outer margin of hindwings; forewing whitish to light brown with yellow to orangish transverse bands and grayish-brown speckling

Range

most of United States and southern Canada

Habitat

larvae are aquatic, living within a silken web in fast-flowing streams; adults may be flushed during the day from nearby vegetation but are nocturnal and attracted to light

Season

adults fly from June to September in the north; probably an extended season in the south

Food

larvae scrape diatoms and other algae from rocks in streams

Life Cycle

adult females enter the water to oviposit, carrying a plastronlike layer of air as a source of oxygen (1)

Remarks

The general pattern of dark "eyespots" on the HW with radiating white and color rays on the FW has been hypothesizd as being mimicry of Salticid jumping spiders.

Print References

Heppner, J. B., 1976. Synopsis of the genus Parargyractis (Lepidoptera: Pyralidae: Nymphulinae) in Florida. Florida Entom. 59(1):5-19.(2) ["Parargyractis" is now Petrophila.]

Lange, W. H., Jr., 1956. A generic revision of the aquatic moths of North America (Lepidoptera: Pyralidae, Nymphulinae). Wasmann J. Biol. 14:59-144.(3)

Munroe, E., 1972. In: Dominick, R. B., et al., The Moths of North America North of Mexico, Fasc. 13.1A, Pyraloidea, Pyralidae (Part). Classey Limited, London.(4)

Sexton, C. W., 2021. Identification and Distribution of the Petrophila fulicalis species group (Crambidae): Taking Advantage of Citizen Science Data. J. Lep. Soc. 75(2):113-127.(5)

Solis, M. Alma, 2019. Aquatic and semiaquatic Lepidoptera, pp.765-789 In: Introduction to Aquatic Insects of North America, R. W. Merritt, K.W. Cummins, and M.B. Berg (Eds.). 5th ed., Kendall/Hunt Publishing Company, Dubuque, Iowa..(6)

Internet References

MPG

Works Cited

1.	Moths of Western North America Powell and Opler. 2009. UC Press.

2.	Synopsis of the genus Parargyracytis (Lepidoptera: Pyralydae: Nymphulinae) in Florida John B. Heppner. 1976. The Florida Entomologist, volume 59, number 1.

3.	A generic revision of the aquatic moths of North America: (Lepidoptera: Pyralidae, Nymphulinae). W. H. Lange, Jr. 1956. Wasmann J. Biol., 14:59-144.

4.	The Moths of North America North of Mexico. Fascicle 13.1A. Scopariinae, Nymphulinae Eugene Munroe. 1972. The Wedge Entomological Research Foundation.

5.	Identification and Distribution of the Petrophila fulicalis species group (Crambidae): Taking Advantage of Citizen Science Data Sexton, C. Journal of the Lepidopterists Society 75(2):113-127.

6.	Aquatic and semiaquatic Lepidoptera, pp.765-789 In: Introduction to Aquatic Insects of North America Solis, M.A. 2019. Kendall/Hunt Publishing Company, Dubuque, Iowa.

Contributed by Troy Bartlett on 7 February, 2005 - 10:26pm
Additional contributions by Robin McLeod, marcie oconnor, Chuck Sexton, Randy Hardy
Last updated 20 June, 2021 - 7:55am

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