Moths of North Carolina
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Pelochrista Members:
42 NC Records

Pelochrista dorsisignatana (Clemens, 1860) - Triangle-backed Pelochrista Moth


Taxonomy
Superfamily: Tortricoidea Family: TortricidaeSubfamily: OlethreutinaeTribe: EucosminiP3 Number: 620930.00 MONA Number: 3116.00 MONA Synonym: Eucosma dorsisignatana
Comments: Pelochrista is a large Holarctic genus of tortricids with around 75% of the 226 described species being native to North America (Wright and Gilligan, 2017). The highest species richness occurs in the western half of North America. The genus has a long and confusing taxonomic history, with many of the species formerly placed in the genus Eucosma. Gilligan et al. (2014) conducted a comprehensive phylogenetic analysis of Pelochrista, Eucosma, and related genera and redefined the genus Eucosma and Pelochrista based on differences in female genitalia. The great majority of Pelochrista species are known only from adults, which likely reflects the fact that the larvae of most species bore into stem bases and roots and are concealed from view. Members of the Asteraceae are the likely hosts for most species (Wright and Gilligan, 2017), but much work need to be done to identifying the hosts.
Species Status: Pelochrista dorsisignatana is one of four species that Wright and Gilligan (2017) recognized as comprising the dorsisignatana species group, with the others being P. oraria, P. similiana, and P. wagneri. All have nearly identical genitalia and the species are recognized based on differences in size, maculation, and/or geographic distribution.
Identification
Field Guide Descriptions: Covell (1984); Beadle and Leckie (2012)Online Photographs: MPG, BugGuide, iNaturalist, Google, BAMONA, GBIF, BOLD                                                                                 
Adult Markings: The head, palps, antennae, and thorax are pale gray to reddish-brown and are concolorous with the forewing ground color, which is overlaid with fine brown to reddish-brown striations and reticulations. The forewing has three prominent reddish brown to blackish brown marks that are thinly edged with white. The first is a wide, semi-oval band that extends from the inner margin at about one-third the wing length and terminates near the middle of the wing. Following this is an equally wide or wider band that begins on the costa just beyond the middle and extends obliquely outwardly where it typically stops just before reaching the inner margin. The region near the costa usually appears faded relative to the remainder of the band. The last mark is a much narrower and lighter postmedian band that begins at the tornus and slants inwardly; it often breaks up just before reaching the costa. The pale strigulae on the distal one-half of costa are either absent or faint and are concolorous with the ground color. The ocellus is absent, and the termen has a narrow salt-and-pepper-colored band that extends from the tornus to the apex. The hindwing is light brown to brownish-gray with a slightly paler fringe.

Pelochrista dorsisignatana and P. similiana are two closely related species. In the latter, the subbasal and median bands are connected versus being widely separated in P. dorsisignatana (Miller 1985). Pelochrista oraria is also somewhat similar, but it is larger, is restricted to coastal and maritime habitats, and has a median band with an oblique branch that tapers to the apex.
Forewing Length: 6.6–11.5 mm (mean = 9.3 mm) for males and 8.8–11.4 (mean = 9.9 mm) for females (Wright, 2011).
Adult Structural Features: This and other members of the dorsisignatana species group have nearly identical genitalia. Wright (2011) and Wright and Gilligan (2017) have illustrations of the genitalia and Wright and Gilligan (2017) provide a general description of the genitalia of the group members as follows. In males, the uncus is triangular and is weakly differentiated from the dorsolateral shoulders of the tegumen. The socii are short and fingerlike, and the phallus mildly tapers distally, with the base closely surrounded by the anellus. The vesica has 8-31 cornuti. The costal margin of the valva is concave, the ventral emargination is shallow, and the neck is short and broad. The cucullus has the dorsal lobe moderately developed, and the apex is broadly rounded. The distal margin is convex and nearly uniform in curvature, while the ventral lobe is weakly developed and the anal angle is broadly rounded. Setation of the medial surface is short and fine.

In females, the papillae anales are flat, moderately setose, and densely microtrichiate along the margins of the ventral opening. The sterigma is Type II, U-shaped, and microtrichiate. The lamella postvaginalis is rectangular, with the lateral margins curled inward. The posterior edge appears to be deeply emarginated due to reduced sclerotization of the medial trough. The medial trough is flanked by hairlike setae and the lamella antevaginalis is ringlike. Sternum 7 is rectangular with the posterior margin indented to about one-third the length of the sterigma. Scaling of sternum 7 is uniform except for a moderately dense band along the posterior margin. The ductus bursae has a patch of sclerotization (sometimes fragmented) near the juncture with the ductus seminalis. The corpus bursae has one large signum, but sometimes with a second vestigial signum in the form of a small sclerotized scar and/or a cluster of sclerotized dots on the membrane.

Wright and Gilligan (2017) noted that male P. dorsisignatana of P. similiana have very similar genitalia and differ only to the extent that the uncus and socii of P. similiana tend to be more strongly developed and more clearly differentiated from the dorsolateral shoulders of the tegumen. Females of these two species have virtually identical genitalia.
Adult ID Requirements: Identifiable from good quality photos of unworn specimens.
Immatures and Development: Capek (1969) found that the larvae are stem and root-borers on goldenrods. The females lay their eggs on stalks close to the ground and the larvae bore downward to the root stalk where they overwinter. With the spring warm-up, the larvae bore upwards and end in the sprouting buds of the new growth where they pupate.
Distribution in North Carolina
Distribution: Pelochrista dorsisignatana has a transcontinental distributed across North America. it ranges across much of southern Canada from British Columbia to Prince Edward Island. In the US it is found throughout the central and eastern states to as far south as the Gulf of Mexico, and in Colorado, the Pacific Northwest, and northern California.
County Map: Clicking on a county returns the records for the species in that county.
Flight Dates:
 High Mountains (HM) ‚Č• 4,000 ft.
 Low Mountains (LM) < 4,000 ft.
 Piedmont (Pd)
 Coastal Plain (CP)

Click on graph to enlarge
Flight Comments: Local populations appear to be univoltine. The adults have been observed from July through November in different regions of the country, with a seasonal peak in most areas from August through October. As of 2022, our records extend from early August through late October.
Habitats and Life History
Habitats: Local populations as associated with goldenrod stands and are found in open or partially shaded habitats with goldenrods.
Larval Host Plants: Fernald (1882) reported that the larvae feed in the roots of Canada Goldenrod (Solidago canadensis) and Capek (1969) observed them feeding on the lower shoots, roots, and emerging buds of both Canada Goldenrod and Giant Goldenrod (S. gigantea). - View
Observation Methods: The adults are attracted to lights.
Wikipedia
Status in North Carolina
Natural Heritage Program Status:
Natural Heritage Program Ranks: GNR S3-S5
State Protection: Has no legal protection, although permits are required to collect it on state parks and other public lands.
Comments: Populations appear to be secure within the state, particularly given that early successional habitats that support the host plants are plentiful.

 Photo Gallery for Pelochrista dorsisignatana - Triangle-backed Pelochrista Moth

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

Recorded by: Chuck Smith on 2023-10-30
Davidson Co.
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Recorded by: Simpson Eason on 2023-10-25
Durham Co.
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Recorded by: Simpson Eason on 2023-10-21
Durham Co.
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Recorded by: John Petranka on 2022-11-02
Orange Co.
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Recorded by: Simpson Eason on 2022-10-28
Durham Co.
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Recorded by: Chuck Smith on 2022-10-25
Davidson Co.
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Recorded by: David George, L. M. Carlson on 2021-10-22
Orange Co.
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Recorded by: Simpson Eason on 2021-10-15
Durham Co.
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Recorded by: Jeff Niznik on 2021-10-11
Wake Co.
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Recorded by: tom ward on 2021-10-04
Buncombe Co.
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Recorded by: Stephen Hall on 2020-10-27
Orange Co.
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Recorded by: Simpson Eason on 2020-10-25
Durham Co.
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Recorded by: Simpson Eason on 2020-10-21
Durham Co.
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Recorded by: Simpson Eason on 2020-10-21
Durham Co.
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Recorded by: Jim Petranka on 2020-10-15
Madison Co.
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Recorded by: Gary Maness on 2020-10-12
Guilford Co.
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Recorded by: Gary Maness on 2020-10-12
Guilford Co.
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Recorded by: Jim Petranka on 2020-10-08
Madison Co.
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Recorded by: Jim Petranka on 2020-10-07
Madison Co.
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Recorded by: Jim Petranka on 2020-10-07
Madison Co.
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Recorded by: Jim Petranka and Becky Elkin on 2020-09-18
Madison Co.
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Recorded by: Jim Petranka and Becky Elkin on 2020-09-18
Madison Co.
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Recorded by: Gary Maness on 2019-10-21
Guilford Co.
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Recorded by: Gary Maness on 2019-10-21
Guilford Co.
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Recorded by: Jim Petranka on 2019-10-15
Madison Co.
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Recorded by: Jim Petranka on 2019-10-15
Madison Co.
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Recorded by: Gary Maness on 2019-10-11
Guilford Co.
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Recorded by: Gary Maness on 2019-10-11
Guilford Co.
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Recorded by: Simpson Eason on 2019-10-09
Durham Co.
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Recorded by: Gary Maness on 2019-10-09
Guilford Co.
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