Moths of North Carolina
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39 NC Records

Achyra rantalis (Guenée, 1854) - Garden Webworm Moth

Taxonomy
Superfamily: Pyraloidea Family: CrambidaeSubfamily: PyraustinaeTribe: PyraustiniP3 Number: 801452.00 MONA Number: 4975.00
Identification
Field Guide Descriptions: Covell (1984); Beadle and Leckie (2012)Online Photographs: MPG, BugGuide, iNaturalist, Google, BAMONA, GBIF, BOLDTechnical Description, Adults: Munroe (1976)Technical Description, Immature Stages: Capps (1967)                                                                                 
Adult Markings: The following description is based mostly on those of Capps (1967) and Munroe (1976). The ground color of the forewing can be various shades of orange, brown or fuscous, with the marking slightly darker than the ground color. The reniform spot is conspicuous and much larger than the orbicular spot. The antemedial line is rather smooth and irregularly angulated, while the postmedial line is denticulate and bowed outward on the costal two-thirds. Both lines can be rather weak and diffuse. The post-medial line is often shaded on the outer margin with a thin line of lighter color, and the area between the postmedial line and the termen is often lighter than the general ground color. The terminal line is broken and consists of a line of 7-8 dark spots. The hindwing is often paler than the forewing and the postmedial line, if evident, is diffuse. Females are usually somewhat darker than the males and tend to have stronger markings.
Wingspan: 17 -23 mm (Capps, 1967)
Forewing Length: 9-10 mm (Powell and Opler, 2009).
Adult Structural Features: Capps (1967) has descriptions and illustrations of the male and female genitalia.
Adult ID Requirements: Identifiable from good quality photos of unworn specimens.
Immatures and Development: The larvae feed on numerous species, including many cultivated plants. The following is a summary of the life history based on Smith and Franklin’s (1954) studies in alfalfa fields in Kansas. The larvae web together the terminal leaves of the main stems and lateral branches to form nests, then feed internally on the leaves. Females deposit their eggs in flat scale-like masses of up to 37 eggs. The hatchlings feed together during the first instar, then disperse to the tops of plants and web together leaves to make nests. The first two instars skeletonize the leaves, while the latter instars consume entire leaves and produce copious amounts of black frass that clings to the webbing. The larvae pass through six instars. When fully grown, they drop to the ground and spin silk cocoons that extend vertically or nearly so just below the surface of the soil. The brownish pupal cases are around 12-13 mm long and are thin, flat, and nearly transparent. They have an open end that faces towards the soil surface that allows the adult to emerge. The pupal stage lasts around 10 days, and the adult crawl up plants soon after they emerge and dry their wings. In Kansas, populations passed through three generations and overwintered as pupae.

The final instar larvae are around 24-25 mm long. The body ground color varies from greenish to brown or nearly black, and there is a narrow mid-dorsal stripe. The head is pale and has netlike amber markings and a fuscous patch on each side at the incision of the posterior margin. The prothoracic shield has two dark bars on each side. The pinacula appear as bold, black spots above the level of the spiracles, while those below the spiracles have pale centers and appear ring-like (or Capps, 1967; Munroe, 1976). Each body segment has three black spots on each side that are arranged in a triangular pattern.
Larvae ID Requirements: Identifiable from good quality photos, especially where associated with known host plants.
Distribution in North Carolina
Distribution: This is a very wide-ranging species that is found in almost every state in the conterminous U.S. except Wyoming, North Dakota and Montana, as well as in Canada (Ontario; Quebec; Nova Scotia), the West Indies and Mexico. As of 2023, all of our records are from the Piedmont and Coastal Plain.
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: As of 2023, we have records from late-March through late-September. Populations in the Coastal Plain are bivoltine, but those in other states such as Kansas and Oklahome can have 3-5 generations per year (Smith and Franklin, 1954) .
Habitats and Life History
Habitats: Local populations are commonly found around crop fields, home gardens, road corridors and other disturbed settings.
Larval Host Plants: The larvae are polyphagous and feed on both cultivated and non-cultivated plants (Smith and Franklin (1954), Capps, 1967; Covell, 1984; Heppner, 2007; Robinson et al., 2010). They commonly feed on garden vegetables and cultivated crops such as alfalfa, amaranths, beans, black-eyed peas, clover, corn, cotton, cowpeas, radishes, soybeans, strawberries, sunflowers, sugar beets and Swiss chard. Other hosts include pigweeds (Amaranthus spp.), Giant Ragweed (Ambrosia trifida), Common Ragweed (A. artemisiifolia), Spearscale Orache (Atriplex patula), Turtleweed (Batis maritima), Lambsquarter (Chenopodium album), guayule (Parthenium argentatum), smartweeds (Polygonum spp.), roses (Rosa), docks (Rumex spp.), sea-purslane (Sesuvium), thistles and undoubtedly many other kinds of weeds. - View
Observation Methods: The adults are attracted to lights, and the larvae are commonly found in vegetable garden and commercial field crops.
Wikipedia
Status in North Carolina
Natural Heritage Program Status:
Natural Heritage Program Ranks: [GNR] S4S5
State Protection: Has no legal protection, although permits are required to collect it on state parks and other public lands.
Comments: This wide-ranging species is common in the eastern half of the state and appears to be secure, in part due to its use of cultivated and weedy plants as a food source.

 Photo Gallery for Achyra rantalis - Garden Webworm Moth

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

Recorded by: Mark Basinger on 2024-04-21
Brunswick Co.
Comment: 		Recorded by: Mark Basinger on 2024-04-21
Brunswick Co.
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Recorded by: Mark Basinger on 2023-09-30
Brunswick Co.
Comment: 		Recorded by: Mark Basinger on 2023-09-03
Brunswick Co.
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Recorded by: Mark Basinger on 2023-08-18
Brunswick Co.
Comment: 		Recorded by: R. Newman on 2022-09-06
Carteret Co.
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Recorded by: R. Newman on 2022-08-31
Carteret Co.
Comment: 		Recorded by: R. Newman on 2022-08-22
Carteret Co.
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Recorded by: R. Newman on 2022-08-17
Carteret Co.
Comment: 		Recorded by: Dean Furbish on 2022-07-28
Wake Co.
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Recorded by: David George, L. M. Carlson on 2022-07-26
Greene Co.
Comment: 		Recorded by: David George, L. M. Carlson on 2022-07-25
Greene Co.
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Recorded by: R. Newman on 2022-05-17
Carteret Co.
Comment: 		Recorded by: R. Newman on 2022-04-29
Carteret Co.
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Recorded by: Michael P. Moralesm on 2021-08-26
Cumberland Co.
Comment: 		Recorded by: Michael P. Moralesm on 2021-08-26
Cumberland Co.
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Recorded by: Dean Furbish on 2021-08-02
Wake Co.
Comment: 		Recorded by: Dean Furbish on 2021-06-27
Wake Co.
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Recorded by: Mark Shields on 2021-05-28
Onslow Co.
Comment: 		Recorded by: R. Newman on 2021-05-17
Carteret Co.
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Recorded by: R. Newman on 2021-04-20
Carteret Co.
Comment: 		Recorded by: Mark Shields on 2020-03-23
Onslow Co.
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Recorded by: Gary Maness on 2019-09-02
Guilford Co.
Comment: 		Recorded by: Stephen Dunn on 2019-08-26
Orange Co.
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Recorded by: Mark Shields on 2019-08-03
Onslow Co.
Comment: 		Recorded by: Salman Abdulali on 2019-07-25
Pitt Co.
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Recorded by: Salman Abdulali on 2019-07-25
Pitt Co.
Comment: 		Recorded by: Gary Maness on 2019-05-24
Guilford Co.
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Recorded by: Salman Abdulali on 2018-09-01
Pitt Co.
Comment: 		Recorded by: Salman Abdulali on 2017-09-03
Pitt Co.
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