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Species Pediasia trisecta - Sod Webworm - Hodges#5413

Pediasia trisecta - Sod Webworm - Hodges#5413 - Pediasia trisecta Large Crambid - Pediasia trisecta Moth - Pediasia trisecta  Sod Webworm - Hodges#5413 - Pediasia trisecta Crambidae: Pediasia trisecta - Pediasia trisecta A Crambinae sp. - Pediasia trisecta Moth - Pediasia trisecta Moth - Pediasia trisecta
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 Crambinae (Crambine Snout Moths)
Tribe Crambini
Genus Pediasia
Species trisecta (Sod Webworm - Hodges#5413)
Hodges Number
5413
Other Common Names
Large Sod Webworm
Greater Sod Webworm
Size
wingspan 23-33 mm
larvae to 28 mm
Identification
Adult: forewing variably brown to pale yellowish-orange, lighter grayish in lower half (along inner margin); surface sprinkled with dark brown scales; dark gray line from base to middle of wing, plus small dark patch closer to outer margin; faint oblique line from middle of wing to apex; terminal line with 4-5 dark dots; fringe checkered dark gray and white; hindwing broader than forewing, light brown to pale grayish-white; fringe whitish; [see pinned image by C.D. Bird]
labial palps project foreward, forming a "snout" (as in other members of this subfamily)

Larva: body pinkish-white to yellowish to light brown, often with paired dorsal and lateral spots on each abdominal segment; head yellowish-brown, brown, or black
Range
all of United States and southern Canada
Habitat
lawns, grassy areas; adults may fly low over lawns during the day, but are primarily nocturnal and attracted to light
Season
adults fly from May to October
Food
larvae feed on grasses (Poaceae)
Life Cycle
sod webworms overwinter as young larvae a few centimeters below soil line among roots of weeds and grasses in silk-lined tubes; in early spring, larvae feed on upper root systems, stems, and blades of grass; they build protective silken webs, usually on steep slopes and in sunny areas, where they feed and develop; pupation occurs in May in underground cocoons made of silk, bits of plants, and soil; adults emerge about two weeks later, are erratic and weak flyers, live only a few days, and feed solely on dew; they rest in the grass or sometimes fly low over the ground during the day, but are primarily nocturnal, becoming active at dusk.
Eggs are deposited indiscriminately over the grass, and hatch in 7-10 days; the most severe damage to turf occurs in July and August when the grass is not growing rapidly; during this hot weather, larvae feed at night or on cloudy days; most species complete 2 or 3 generations per year, with approximately 6 weeks elapsing between egg deposition and adult emergence.
[adapted from text by North Carolina State U.]
See Also
other Pediasia species lack checkered gray and white fringe on forewing (also see images of related genera & species on MPG page)
Internet References
live and pinned adult images by various photographers, plus common name reference [Sod Webworm] (Moth Photographers Group)
pinned adult image by C.D. Bird, plus description, distribution, flight season, biology, common name reference [Greater Sod Webmworm] (Strickland Entomological Museum, U. of Alberta)
live and pinned adult images (Larry Line, Maryland)
pinned adult image plus description, distribution, foodplant, common name reference [Large Sod Webworm], similar species (Gerald Fauske, Moths of North Dakota)
biology of webworms in general including Pediasia trisecta (North Carolina State U.)
presence in Texas; list (Dale Clark, Texas)
presence in Florida; list (John Heppner, Florida State Collection of Arthropods)
presence in California; list (U. of California at Berkeley)