Moths of North Carolina
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41 NC Records

Exyra semicrocea (Guenée, 1852) - No Common Name


Taxonomy
Superfamily: Noctuoidea Family: NoctuidaeSubfamily: PlusiinaeTribe: PlusiiniP3 Number: 931189.00 MONA Number: 9024.00
Comments: One of three members of this genus, all of which are highly associated with Pitcher Plants in the genus Sarracenia, which occurs only in eastern North America. All three species have been recorded in North Carolina. This genus was formerly placed in the Acontiinae (e.g., Forbes, 1954) but was moved to the Plusiinae by Lafontaine and Poole (1991).
Identification
Field Guide Descriptions: Online Photographs: MPG, BugGuide, iNaturalist, Google, BAMONA, GBIF, BOLDTechnical Description, Adults: Jones (1921); Forbes (1954); Lafontaine and Poole (1991)Technical Description, Immature Stages: Jones (1921); Forbes (1954); Lafontaine and Poole (1991); Wagner et al. (2011)                                                                                 
Adult Markings: A medium-small, black-and-yellow Noctuid. The head and front half of the thorax are dark, blackish brown, differing from the crimson-and-yellow found in Exyra fax but very similar to the pattern shown by E. ridingsii. Unlike ridingsii, semicrocea lacks a black antemedian line on the forewings, which are usually divided into a yellow basal area and a blackish terminal area, with the line separating the two zones running fairly straight across the wings. Rarely, all yellow forms occur (see illustrations in Lafontaine and Poole, 1991). Ponometia semiflava is another similar sized moth with yellow basal and black terminal areas on its wings. However that species has an all yellow head and thorax and the line dividing the black and yellow portions of the wings runs at a slant across the wings rather than straight-across. Although there has been some confusion in the past, P. semiflava is not associated with Pitcher Plants, although it also occurs in open Longleaf Pine communities where its host plants -- Goldenaster and other composites -- occur.
Adult Structural Features: Male and female genitalia are illustrated in Lafontaine and Poole (1991).
Adult ID Requirements: Identifiable from good quality photos of unworn specimens.
Immatures and Development: Mature larvae are wine red with white, intersegmental bands. Unlike Exyra fax but similar to E. ridingsii, elongated lappets (pinnacula or warts) occur on the anterior portion of the abdomen that apparently help the larvae from getting stuck in the narrow bottom reaches of the pitcher plant tubes (Jones, 1921). In E. semicrocea, the lateral (= subdorsal) lappets on the thorax are smaller than in ridingsii and are much shorter than those on the abdomen and about the same length of the dorsal warts on the thoracic segments (Lafontaine and Poole, 1991; Wagner et al., 2011). The life history of the Exyra species was well-described by Frank Morton Jones, who studied them initially in Richmond County, NC (Jones, 1904). All life stages are closely associated with their host plants: eggs are laid within the entrance to the pitcher; larvae seal off the entrances to the tubes to create a sealed feeding chamber; both overwintering by larvae and pupation typically occurs within the bases of the tubes; and adults typically rest within the tubes between dispersive flights (see Jones, 1921, for details, including slight differences between species).
Larvae ID Requirements: Identifiable from good quality photos, especially where associated with known host plants.
Distribution in North Carolina
Distribution: Formerly occurred in the Mountains, Piedmont, and Coastal Plain, but appears to have been extirpated from the first two regions; recent records are all from the southern part of the Coastal Plain, including the Fall-line Sandhills.
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: Adults occur throughout most of the growing season, from April through the end of September, with three apparent peaks in activity but no definite separation between flights
Habitats and Life History
Habitats: All of our records come from peatlands, including Low Pocosin and Pocosin Openings; peaty areas in Wet Pine Savannas and Sandhill Seeps; and from boggy, sediment-filled portions of beaver ponds and other shallow impoundments. Always found in association with its host plants.
Larval Host Plants: Stenophagous, feeding only on Pitcher Plants (Sarracenia spp.) but apparently using all seven species in that genus (Jones, 1921; Lafontaine and Poole, 1991). - View
Observation Methods: Comes well to blacklights. Both adults and larvae can be found by inspecting the tubes of their host plants.
Wikipedia
See also Habitat Account for General Herbaceous Peatlands
Status in North Carolina
Natural Heritage Program Status: SR
Natural Heritage Program Ranks: G3G4 S2S3
State Protection: Listed as Significantly Rare by the Natural Heritage Program. That designation, however, does not confer any legal protection, although permits are required to collect it on state parks and other public lands.
Comments: This species, along with other members of this genus, is highly specialized on a habitat type that naturally had a extremely patchy distribution and that underwent a severe reduction in both its range and overall extent since European settlement due to conversion to croplands and pine plantations and to suppression of the natural fire regime. These trends, moreover, are still continuing. Surveys conducted by the Natural Heritage Program in 2009-2011 in the Sandhills and the Uwharrie Mountain region of the eastern Piedmont documented a particularly strong recent decline in Pitcher Plant populations. Even where a few plants have managed to survive -- or even where Sarracenia populations have recovered due to recent prescribed burning -- Exyra species could not be found, even where they had been seen as recently as the 1990s (S. Hall, upubl. data). While populations of Exyra semicrocea still exist on several large areas of habitat located on military lands, state parks, game lands, and private nature preserves, all of those are dependent on appropriate use of prescribed burning to support their metapopulations. Too thorough or frequent burning, however, also jeopardizes this species, particularly in the small, isolated populations that are all that are left in some areas. Stephens et al. (2011) suspect that prescribed burning was the cause for the extirpation of the only known population of this species in the Mountains of North Carolina.

 Photo Gallery for Exyra semicrocea - No common name

Photos: 8

Recorded by: Mark Shields on 2020-06-26
Onslow Co.
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Recorded by: Mark Shields on 2020-06-26
Onslow Co.
Comment:
Recorded by: Mark Shields on 2020-06-26
Onslow Co.
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Recorded by: Mark Shields on 2020-05-05
Onslow Co.
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Recorded by: ASH, S. Hall on 2007-05-21
Moore Co.
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Recorded by: Mark Shields on 2006-05-14
Onslow Co.
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Recorded by: Mark Shields on 2005-09-11
Onslow Co.
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Recorded by: SPH, SH, CH on 2000-05-23
Moore Co.
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