Species Autographa californica - Alfalfa Looper Moth - Hodges#8914

8914

Alfalfa Looper (larva)

CALIFORNICA: the type specimen was collected in California, and named Plusia gamma var. californica by Speyer in 1875 (Markku Savela, FUNET)

wingspan 36-42 mm

Adult: grayish-black moth with silvery or bluish sheen in fresh specimens; forewing mottled pale gray in basal and subterminal areas, and dark blackish-brown in lower median area and along subterminal line; AM and PM lines and area below stigma dark reddish-brown; stigma silvery white, forming outward curving arc with rounded tip and a widely-separated fork at upper end; black dash connects PM line and ST line about one-third distance from costa along ST line (the dash is the most prominent of several black-outlined veins in subterminal area)

hindwing pale grayish in basal half, shading (usually abruptly) into wide dark terminal band; antennae simple; sexes alike

Larva: body green with distinct white spiracular line and faint white discontinuous dorsal lines; two pairs of mid-abdominal prolegs (typical of Plusiinae larvae)

Alaska to California and northern Mexico, east to New Mexico, north to Manitoba

open meadows, hayfields, croplands, gardens and woodland edges; adults are active day and night, and are attracted to light

adults fly from February to November in the south; May to October in the north

larvae present from early spring through late fall

larvae feed on leaves of more than 50 genera of herbaceous plants and woody shrubs; legumes such as alfalfa and clover are common hosts

adults nectar on a variety of low plants

several generations per year

The Autographa californica nuclear polyhedrosis virus is a Baculovirus that has been used in biocontrol of this species. When a larva eats leaves contaminated with the virus, the virus reproduces inside the larva's body, eventually killing the larva before it can pupate. Larvae killed by baculoviruses have a characteristic shiny-oily appearance, and are often seen hanging limply from vegetation. They are extremely fragile to the touch, rupturing to release fluid filled with many billions of infective virus particles. See the Cornell University page for images and more info.

the black dash along the ST line (described in Identification section above) is diagnostic, separating californica from the very similar A. pseudogamma (compare images of both species)

several Syngrapha species are similar but have either yellow in the hindwing and/or a differently-shaped stigma and/or lack black-margined veins in ST area of forewing (see thumbnail images of pinned adults in the subfamily Plusiinae)

live adult images (U. of British Columbia Botanical Garden)

live adult image (Peggy Greb, USDA, forestryimages.org)

pinned adult image plus habitat, seasonality, description, biology, food plants, distribution (U. of Alberta)

pinned adult image and other info (California Dept. of Food and Agriculture)

pinned adult images (Bruce Walsh, Moths of Southeastern Arizona)

live larva image plus description, biology, food plants, seasonality (Jeffrey Miller, Caterpillars of Pacific Northwest Forests and Woodlands; USGS)

information on Baculoviruses in connection with Autographa californica (Vince D'Amico, Hamden, Connecticut, courtesy of Cornell U.)