Moths of North Carolina
Scientific Name:
Common Name:
Family (Alpha):
« »
View PDFLimacodidae Members:
Tortricidia Members:
10 NC Records

Tortricidia pallida of authors (not Herrich-Schäffer, 1854) - Red-crossed Button Slug Moth

Superfamily: Zygaenoidea Family: LimacodidaeP3 Number: 57a0062 MONA Number: 4653.00 MONA Synonym: Tortricidia pallida
Comments: This is one of three closely related species in this genus that occur in North America, all of which occur in North Carolina.
Species Status: The adults of this species and T. flexuosa are two forms that have been treated as both a single species and two species over the years. Many of the specimens cannot be differentiated based on either the larvae or adult coloration, patterning, or external morphology. Other evidence such as genitalia or molecular barcoding data have also been found to be of little value. Experts that specialize in this group suspect that they are conspecific (Wagner, 2005; MPG). As such they are perhaps best treated as a poorly resolved species complex, T. pallida/flexuosa. We continue to recognize both species, with the caveat that many of our identifications based on external features such as coloration and patterning are provisional. Another issue involves nomenclature. As noted by Epstein and Fiesler (in Pohl and Nanz, eds.; 2023) and reported here verbatim, the original description of T. pallida by Herrich-Schäffer was only an illustration, one that matches what has been considered to be T. flexuosa by authors since. By priority, this would make the more marked phenotypes to be true T. pallida rather than those with little or no markings: the T. pallida of authors that followed. Tortricidia pallida of authors would be another taxon, perhaps T. flavula, which matches the less marked phenotype but is a darker, more vivid orange-brown. Pending further research, for expediency Epstein and Fiesler treated the species as they have most recently been known, and append "of authors" to both names to reflect the uncertainty in application of the names as they were described. In the text that follows, we refer to "Tortricidia pallida of authors" as simply Tortricidia pallida.
Field Guide Descriptions: Online Photographs: MPG, BugGuide, iNaturalist, Google, BAMONA, GBIF, BOLDTechnical Description, Adults: Forbes (1923)Technical Description, Immature Stages: Wagner (2005)                                                                                 
Adult Markings: In this form the forewing varies from warm brown to light pinkish brown or pale buff. Like T. flexuosa, the forewing can be either unmarked or show a faintly patterned, more or less straight brown or reddish AM line and rounded PM line -- both which are typically incomplete or faint. This species is indistinguishable from the light form of T. flexuosa (see comments above). Tortricidia pallida also resembles Heterogenia shurtleffi. Given the degree of individual variation among both species, they also might best be considered to be largely indistinguishable from one another, with DNA analyses the only sure way to separate the adults.
Adult ID Requirements: Identifiable only by close inspection of structural features or by DNA analysis.
Immatures and Development: The slug-like caterpillar is very similar to others in the genus. It is pale green and oval in shape with broad, reddish (sometimes greenish), cross-shaped patches on the dorsum (hence the common name). The side "arms" are the widest and extend to the bottom of the segment edges. The anterior arm narrows to a thin line while the posterior arm tends to be more broadly triangular than its congeners (Wagner, 2005).
Distribution in North Carolina
Distribution: Tortricidia pallida is thought to range across much of the eastern US and into southern Canada (Ontario; Quebec; Nova Scotia). The exact range is difficult to define because of the difficulty of confidently assigning specimens to species (see above). Specimens that we have assigned to this species have been found in all three physiographic regions, but are most common in the lower elevations in the mountains.
County Map: Clicking on a county returns the records for the species in that county.
Flight Dates:
 High Mountains (HM) ≥ 4,000 ft.
 Low Mountains (LM) < 4,000 ft.
 Piedmont (Pd)
 Coastal Plain (CP)

Click on graph to enlarge
Flight Comments: The adults have been observed from May through September in different areas of the range. As of 2023 our records extend form mid-June through late-August.
Habitats and Life History
Habitats: This and our other Tortricidia species are generally found in deciduous woodlands, woodland edges, and wooded residential areas.
Larval Host Plants: The feed on deciduous trees such as beeches (Fagus), cherries (Prunus), oaks (Quercus), and willows (Salix; Wagner, 2005). - View
Observation Methods: The adults are attracted to lights to some extent.
Status in North Carolina
Natural Heritage Program Status: GNR [SU]
Natural Heritage Program Ranks:
State Protection: Has no legal protection, although permits are required to collect it on state parks and other public lands.
Comments: Members of the T. pallida/flexuosa complex appear to be relatively common across the state, but because of the identification challenges, a clear picture of the status of T. pallida/flexuosa seems unlikely to be resolved in the near future. Although it is tempting to assign specific names to any adults encountered, given the taxonomic uncertainties it is safest to call any given individual "Tortricidia sp."

 Photo Gallery for Tortricidia pallida of authors - Red-crossed Button Slug Moth

Photos: 2

Recorded by: K. Bischof on 2023-07-17
Transylvania Co.
Recorded by: Paul Scharf,B. Bockhahn, K. Kittelberger on 2012-07-24
Ashe Co.