Moths of North Carolina
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43 NC Records

Herpetogramma fluctuosalis (Lederer, 1863) - Greater Sweetpotato Webworm Moth



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Taxonomy
Superfamily: Pyraloidea Family: CrambidaeSubfamily: PyraustinaeTribe: SpilomeliniP3 Number: 801195.00 MONA Number: 5244.00
Comments: One of 28 species in this genus that occur in North America (Solis, 2010; Handfield and Handfield, 2011), nine of which have been recorded in North Carolina
Species Status: Capps (1964) noted that the type and paratypes from Louisiana had labels indicating that they were reared on sweet potato by C. E. Smith in 1915. However, we are unaware of any records since then indicating that this species uses Sweet Potato. We are also unaware of any state agricultural agencies that treat this species as a pest of Sweet Potato. Thus, the common name appears to be a misnomer and a more relevant name may be in order.
Identification
Field Guide Descriptions: Online Photographs: MPG, BugGuide, iNaturalist, Google, BAMONA, GBIF, BOLDTechnical Description, Adults: Solis (2010)                                                                                 
Adult Markings: In this species the head, thorax, abdomen and ground color of the wings are all concolorous and are typically pale yellowish, tan or dull yellowish-brown. The markings on the forewing are dark brown, and include a slightly irregular antemedial line at around one-fourth the wing length that is followed by an orbicular spot and a wider, curved reniform spot. The area between the orbicular and reniform spots is not noticeably white as seen in some Herpetogramma species. The postmedial has a curved portion that projects from the costa and meets the remainder of the line that has a stepped pattern, with a toothed portion that runs parallel to the termen, a connecting line that runs parallel to the inner margin, and a final portion that runs parallel to the termen to the inner margin near the middle of the wing. Heavy dark brown shade occurs along the costa to the apex, then continues as a broad subterminal band that is often toothed or zig-zagged basally. A gap of lighter ground color is present between the band and the postmedial line.

The hindwing is similar, but lacks the antemedial line and reniform spot. A discocellular dot is present and the postmedial line is similar to that of the forewing. The subterminal region is very weakly shaded relative to that on the forewing, and a zig-zagging subterminal line is present that is usually masked by dark shading on the forewing. Both the forewing and hindwing have a dark marginal line and a two-toned fringe, with the base darker than the outer half.

This species is best separated from our other Herpetogramma species by the absence of a noticeably white area between the orbicular and reniform spots, and in having a light-colored gap between the postmedial line and the darker subterminal shading. Herpetogramma bipunctalis is similar but has two prominent dark brown spots on sternite 2 of the abdomen.
Wingspan: 22-25 mm (Capps, 1964)
Adult Structural Features: Capps (1964) has descriptions and illustrations of the male and female genitalia (as Pachyzancla ipomoealis).
Structural photos
Adult ID Requirements: Identifiable from good quality photos of unworn specimens.
Immatures and Development: The larvae are leaf folders that feed on broad-leaf herbaceous species such as Lizard's-tail and Broadleaf Arrowhead. The larvae usually fold a portion of a leaf over to make a shelter, then skeletonize patches of tissue from the leaf. The larvae feed both within the shelter and in the area immediately surrounding the shelter. They may later consume entire portions of the leaf. Pupation occurs within the shelter. The later instars have dull white bodies with each segment having a pair of light brown to black pinacula dorsally and a single one laterally on each side. The head is shiny black, while the prothoracic shield can be either dull white with a pair of blackish spots dorsally or completely shiny black depending on the instar.
Distribution in North Carolina
Distribution: Herpetogramma fluctuosalis is found in Central America, the West Indies, and the eastern U.S. from southern New York southward to southern Florida, and westward to eastern Texas, eastern Oklahoma, Missouri, Illinois and Indiana. As of 2023, all of our records are from the Coastal Plain and Piedmont, except for one low-elevation site in the Blue Ridge.
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
Immature 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 fly from April through December in Florida, and mostly from June through October farther north. As of 2023 our records range from mid-May through late-October. Populations in North Carolina appear to have two or three generations per year.
Habitats and Life History
Habitats: The majority of our records come from forb-rich wetlands, including marshes and lakeshores.
Larval Host Plants: The larvae appear to be polyphagous, but the hosts are rather poorly documented. Tracy Feldman found larvae on two wetland species in North Carolina, Lizard's-tail (Saururus cernuus) and Broadleaf Arrowhead (Sagittaria latifolia). Heppner (2003) noted that the larvae feed on False Nettle (Boehmeria cylindrica) and Sweet Potato (Ipomoea batatas). Heppner's report of this species using Sweet Potato is apparently from Capps (1964), who noted that the type and paratypes from Louisiana had labels indicating that they were reared on Sweet Potato by C. E. Smith in 1915. However, we are unaware of any records since then indicating that this species uses Sweet Potato, which suggests that it may not be a valid host. This species is also not listed as a pest of Sweet Potato in North Carolina by the NC Department of Agriculture, or by any other agricultural department of other states that we are aware of. Based on the habitats where we have found this species, False Nettle and other wetland forbs seem to be the most likely hosts. - View
Observation Methods: The adults are attracted to lights.
Wikipedia
See also Habitat Account for General Broadleaf Herbaceous Mires
Status in North Carolina
Natural Heritage Program Status:
Natural Heritage Program Ranks: GNR [S3S4]
State Protection: Has no legal protection, although permits are required to collect it on state parks and other public lands.
Comments: Populations in North Carolina appear to be relatively secure, although the historical loss of wetlands in North Carolina has undoubtedly adversely affected this species.

 Photo Gallery for Herpetogramma fluctuosalis - Greater Sweetpotato Webworm Moth

46 photos are available. Only the most recent 30 are shown.

Recorded by: David George, Stephen Dunn, Jeff Niznik, Larry Chen on 2023-10-28
Orange Co.
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Recorded by: Mark Basinger on 2023-10-14
Wilson Co.
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Recorded by: Mark Basinger on 2023-10-02
Wilson Co.
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Recorded by: Jim Petranka and Becky Elkin on 2023-09-25
Madison Co.
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Recorded by: Mark Basinger on 2023-09-24
Wilson Co.
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Recorded by: Mark Basinger on 2023-09-21
Wilson Co.
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Recorded by: David George, Jeff Niznik on 2023-09-20
Durham Co.
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Recorded by: David George on 2023-09-13
Durham Co.
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Recorded by: Mark Basinger on 2023-09-06
Wilson Co.
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Recorded by: Mark Basinger on 2023-09-06
Wilson Co.
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Recorded by: Mark Basinger on 2023-09-05
Wilson Co.
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Recorded by: Mark Basinger on 2023-09-05
Wilson Co.
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Recorded by: David George, Jeff Niznik on 2023-07-19
Durham Co.
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Recorded by: David George, Jeff Niznik, Rich Teper on 2023-05-21
New Hanover Co.
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Recorded by: David George, Jeff Niznik on 2023-05-12
Durham Co.
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Recorded by: Dean Furbish on 2022-10-01
Wake Co.
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Recorded by: John Petranka on 2022-09-21
Orange Co.
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Recorded by: Jeff Niznik on 2022-08-18
Chatham Co.
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Recorded by: Jeff Niznik on 2022-05-25
Chatham Co.
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Recorded by: David L. Heavner on 2021-10-15
Chatham Co.
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Recorded by: Michael P. Morales on 2021-09-27
Sampson Co.
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Recorded by: Michael P. Morales on 2021-09-27
Sampson Co.
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Recorded by: Michael P. Morales on 2021-09-27
Sampson Co.
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Recorded by: Jeff Niznik on 2021-07-29
Wake Co.
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Recorded by: Richard Teper on 2021-07-02
Orange Co.
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Recorded by: Dean Furbish on 2021-06-28
Wake Co.
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Recorded by: Darryl Willis on 2021-06-17
Cabarrus Co.
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Recorded by: Tracy S Feldman on 2020-10-07
Scotland Co.
Comment: Larva found in tied Saururus cernuus leaf, with frass and damage. Larvae reared to adulthood and adult emerged 11/20/2020. The identity of the adult was confirmed by JoAnne Russo.
Recorded by: Tracy S Feldman on 2020-10-07
Scotland Co.
Comment: Larva found in tied Saururus cernuus leaf, with frass and damage. Larvae reared to adulthood and adult emerged 11/20/2020. The identity of the adult was confirmed by JoAnne Russo.
Recorded by: Tracy S Feldman on 2020-10-07
Scotland Co.
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