Speranza ribearia
Currant Spanworm
NatureServe Global Rank: G4
Virginia State Rank: S2S3
VA DGIF Tier: None
Federal Legal Status: None
Virginia Legal Status: None
Description: The wings are translucent yellow with a broad, diffuse pm line on the forewing, grayish except over the veins. The forewing basal and pm. areas are mostly gray. The wingspan is 30-31 mm. Females have variable amounts of the pm line, sometimes represented only by a few spots. Males tend to be grayish white, with faint markings on the forewing, and three spots along the leading edge. The broad pm line is best represented on the trailing edge of the wing, either lacking or less apparent on the leading edge.
Similar species: A few other Speranza species are similar, but generally lack the yellow coloration. The few that are also yellow can be distinguished by the shape of the broad pm line. Males are more difficult but generally lack the darker speckling of various other Speranza species.
North American Range: New Hampshire and Vermont to Maryland and Virginia, west to Nebraska and Oklahoma; across the Canadian provinces from Alberta to Quebec.
VA Observations by Locality: Page | Bath | Page | Warren
Flight season and broods: May and July.
Habitat and Food Plants: The larva feeds on Ribes species, especially Black Currant. They live in various forested wetlands and woodlands, where the host can be found.
Behavior and Ecology: Larvae will drop on silk strands when disturbed. This species overwinters as an egg.
Population trend and potential threats: This species has become much less common since the currant eradication efforts that took place in the 1920's to the 1960's. With that being said, it can occasionally be common enough to be a pest in commercial currant farms.
Management practices: None yet.
References: Covell, Charles V. Covell, Jr.; A Field Guide to Moths of Eastern North America; Special Publication No. 12; Virginia Museum of Natural History in association with the Smithsonian Institution; 1984, 2005. P. 347.
Moth Photographers Group at the Mississippi Entomological Museum at Mississippi State University. Web application at: http://mothphotographersgroup.msstate.edu/large_map.php?hodges=6274 Accessed: 21Apr2013
NatureServe. 2012. NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1. NatureServe, Arlington, Virginia. Available http://www.natureserve.org/explorer. (Accessed: November 8, 2012 ).
Wagner, D. L. 2005. Caterpillars of Eastern North America: A Guide to Identification and Natural History. Princeton University Press, Princeton, NJ. 512pp.