Other Common Names
Southern Beet Webworm (larva)
Synonyms and other taxonomic changes
Herpetogramma bipunctalis (Fabricius, 1794)
Phalaena bipunctalis Fabricius, 1794
Explanation of Names
bipunctalis is derived from Latin for Two Points, refering to the two dark spots on the dorsal abdominal of the adult.
Adult: forewing light yellowish-brown with two conspicuous black discal spots, the outer spot larger; AM line a shallow S-shaped curve; PM line irregular, with convex lobe near midpoint, and deep indentation near inner margin; ST line sharply-toothed but usually only visible as a dividing line between light median area and slightly darker shading in terminal area; hindwing similarly colored but with only one discal spot and irregular median line; adults rest with forewings spread, revealing much of hindwings.
New England to Florida, west to Texas, north to Illinois
also occurs south to Central America
larvae are aquatic; adults may be flushed from nearby vegetation during day but are nocturnal and attracted to light
adults fly from June to October in the north; possibly all year in the south
larvae are generalist feeders of several plant families including Amaranthaceae, Chenopodiaceae, Hydrangeaceae, Leguminosae, Rubiaceae, Solanaceae, and others (HOSTS database
The larvae may have potential in the biological control of Alligatorweed, which chokes waterways in the south.
H. phaeopteralis and aeglealis have darker brown forewings with indistinct discal spots; other species of Herpetogramma have white spots or patches in the forewing.
pinned adult image
by John Glaser, plus status and flight season in Maryland (Larry Line, Maryland)