Moths of North Carolina
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Argyrotaenia Members:
32 NC Records

Argyrotaenia occultana Freeman, 1942 - Fall Spruce Needle Moth


Taxonomy
Superfamily: Tortricoidea Family: TortricidaeSubfamily: TortricinaeTribe: ArchipiniP3 Number: 620266.00 MONA Number: 3607.00
Comments: The genus Argyrotaenia contains approximately 100 described species, with most occurring in Nearctic and Neotropical regions. Thirty-six species are currently recognized in North America.
Identification
Field Guide Descriptions: Online Photographs: MPG, BugGuide, iNaturalist, Google, BAMONA, GBIF, BOLDTechnical Description, Adults: Freeman (1942)Technical Description, Immature Stages: Brown and McGuffin (1942)                                                                                 
Adult Markings: The following is based in part on the original description by Freeman (1942). The head, thorax, antenna, and outer side of the palps are fuscous. The ground color of the forewing is white and is overlain to varying degrees with fine reticulations of light to dark-brown. There are three conspicuous dark brown to blackish regions on the forewing that include the basal fourth to third of the wing, a median band, and a costal spot. The basal area is dark brown, with its outer margin defined by a darker line that starts either at the costa, or near the costal one-quarter, and extends obliquely outward to the median vein where a small tooth projects posteriorly. From there it angles obliquely inward to terminate on the posterior margin.

The median band is dark brown to blackish and is broad and distinct. It starts at the costa just before the basal half and extends obliquely outward to the outer third of the posterior margin. In North Carolina specimens and those from elsewhere, the dorsal half is often noticeably lighter that the costal half. The anterior margin typically has a conspicuous hook and associated notch at the costal one-third, and the region between the hook and the costa is narrower than the remaining dorsal two-thirds of the band. The final mark is a conspicuous dark brown to blackish, sub-triangular, costal spot on the apical third of the wing that tends to be faintly connected to a lighter colored sub-tornal spot. The fringe is fuscous and tends to become lighter in the tornal region. The hindwing is uniformly shining smoky and the fringe is light with a dark basal line.

This species is most easily confused with A. velutinana, but in the latter the dark basal region is largely confined to the dorsal half and lacks a darker line on the outer margin. The overall coloration of the markings are dark brown to blackish on A. occultana versus having a more reddish-brown caste for A. velutinana. In North Carolina A. occultana flies during March and April versus a far more extensive flight season for A. velutinana.
Wingspan: 17-19 mm (Freeman, 1942).
Adult ID Requirements: Identifiable from good quality photos of unworn specimens.
Immatures and Development: The larvae grow to 15 mm in length and feed on spruces, hemlocks and other conifers. The older instars bind the needles of the host plant together with silk to construct a feeding shelter (Maier et al., 2011). The final two instars are green with a darker bluish-green mid-dorsal stripe. The head is yellowish-green and is conspicuously marked with eight brown to black stripes formed by large coalesced circular dots (Brown and McGuffin, 1942). The head markings are often orange-brown on earlier instars. The mature instars also have a brown spot near the stemmata (cluster on simple eyes) and a horizontal dark bar behind the stemmata. The greenish thoracic legs have two dark brown spots near the middle and a dark tip.
Larvae ID Requirements: Identifiable from good quality photos, especially where associated with known host plants.
Distribution in North Carolina
Distribution: Argyrotaenia occultana has northern affinities and occurs in a wide swath from Alaska eastward through much of southern Canada to Nova Scotia and vicinity. In the US it occurs from the New England states westward to Minnesota, then southward mostly through the Appalachian region where scattered populations are found to as far south as eastern Tennessee and western North Carolina. As of 2023, our only records are from a single site in Madison County.
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)

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