Moths of North Carolina
Scientific Name:
Common Name:
 Family (Alpha):
« »
View PDFTortricidae Members:
Olethreutes Members:
3 NC Records

Olethreutes tilianum (Heinrich, 1923) - Basswood Olethreutes

Olethreutes tilianumOlethreutes tilianum
Taxonomy
Superfamily:
Tortricoidea		 Family:
Tortricidae		Subfamily:
Olethreutinae		Tribe:
Olethreutini		P3 Number:
51a0563		 MONA Number:
2795.00
Comments: Olethreutes is a large genus with over 130 recognized species worldwide. North America has around 80 recognized species, with at least 37 species occurring in North Carolina. Some species are very difficult to identify due to interspecific similarities in color and forewing pattern and only subtle differences in genitalia (Gilligan et al., 2008). In many instances, knowledge of the host plant is essential for a confident determination. All of the Nearctic species are leaf-tiers or leaf-rollers on deciduous trees and shrubs.
Species Status: There is one record for Olethreutes tilianum (BOLD specimen: LGSMF076-06) from 'Swain County', Tennessee that may or may not have meant to refer to Swain County, North Carolina. The collection site was not sufficiently specific to determine the state, but appeared to be at or near the NC-TN line. =
Identification
Field Guide Descriptions: Online Resources: MPG, BugGuide, iNaturalist, Google, BAMONA, GBIF, BOLD                                                                                 
Adult Markings: The forewing of this species has tawny to light grayish-brown interfascial regions that are reticulated with darker striations. The medial fascia and other larger marks tend to be dark brown to blackish-brown (sometimes lighter) and are margined with a line of pale scales. The medial fascia consists of three posterior projections that include a relatively large patch along the inner margin, an elongated tooth in the middle that gradually tapers to a fine point, and an elongated costal tooth that also tapers to a fine point. The costal and middle tooth are typically not joined at their bases as seen in many of our Olethreutes and the meddle tooth is also often not joined to the patch along the inner margin. The other dark marks include an outwardly oblique basal patch that extends from the base of the inner margin before terminating near the center of the wing, a large pretornal patch along the inner margin, and an elongated, elliptical, postmedial bar. The area of the costal beyond the costal tooth has a series of 4-5 small, reddish to blackish, triangular spots that alternate with paler strigulae. The hindwing varies from brownish-gray to medium brown.

This species closely resembles Olethreutes permundana, O. lacunanum, and certain forms of O. nigranum (Heinrich, 1926; Gilligan et al., 2008). Olethreutes permundana is generally similar in patterning, but tends to be lighter-colored overall. The costal and middle teeth of O. tilianum are normally not joined at the base, or very weakly so, and are more finely tapered to a sharp point, while O. permundana typically has the two clearly joined at the base, with the middle tooth in particular, shorter and more bluntly rounded at the end. Olethreutes lacunanum also has the teeth joined at the base, with the middle tooth being more pointed than that of O. permundana and very similar to that of O. tilianum. These two species can be separated using genitalia (Gilligan et al., 2008). The light forms of O. nigranum are also similar, but the costal and middle teeth are shorter and normally joined at the base.
Forewing Length: 9.0-10.0 mm (Gilligan et al., 2008).
Adult Structural Features: Gilligan et al. (2008) have illustrations of the male and female genitalia and note that adults of O. tilianum are very similar in size and appearance to O. lacunanum and some forms of O. nigranum. In O. tilianum and O. nigranum, the digitus arises near the cucullus, while in O. lacunanum the digitus is reduced to a rounded lobe at the distal end of the sacculus. Females of all three species lack a signum in the corpus bursae.
Adult ID Requirements: Identifiable from photos showing hindwings, abdomen, or other specialized views [e.g., frons, palps, antennae, undersides].
Immatures and Development: Larvae feed in tied leaves of basswood (Heinrich, 1926), but details of the larval life history are undocumented.
Distribution in North Carolina
Distribution: Olethreutes tilianum is found in eastern North America and is generally associated with cool climates. Specimens have been found in Canada in Manitoba, Ontario, Quebec and New Brunswick. In the US the range extends from Maine and other New England states westward through the Great Lake region to Minnesota, and southward to Iowa, Illinois, eastern Kentucky, eastern Tennessee, Pennsylvania and New Jersey. As of 2024, our only records are from Swain and Graham counties in the Blue Ridge.
County Map: Clicking on a county returns the records for the species in that county.
Olethreutes tilianum
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, with a seasonal peak typically in July and August. As of 2024, both of our records are from mid-July.
Habitats and Life History
Habitats: Local populations are associated with rich, mesic forests that have American Basswood present.
Larval Host Plants: The larvae are thought to feed only on American Basswood (Tilia americana; Heinrich, 1926; Gilligan et al., 2008).
Observation Methods: The adults are attracted to lights. More information is needed on the larval life history, and we encourage individuals to seek out the larvae on basswood leaves.
Wikipedia
See also Habitat Account for Rich Dry-Mesic Hardwood Forests
Status in North Carolina
Natural Heritage Program Status:
Natural Heritage Program Ranks: GNR SU
State Protection: Has no legal protection, although permits are required to collect it on state parks and other public lands.
Comments: This species is questionable in terms of its occurrence in North Carolina, but likely does occurs in the Blue Ridge in Swain County (see note above).

 Photo Gallery for Olethreutes tilianum - Basswood Olethreutes

Photos: 2

Recorded by: David George, Stephen Dunn, Jeff Niznik, Rich Teper, Becky Watkins on 2023-07-30
Swain Co.
Comment: 		Recorded by: Vin Stanton on 2013-07-16
Graham Co.
Comment: