one-spotted variant

not listed

NNR - Unranked

SNR - Unranked

not listed

One-spotted variant is a medium-sized geometer moth. It occurs in the United States and southern Canada east of the Great Plains and in the Pacific Northwest. It is found in June and July in deciduous and mixed woodlands. Larvae feed on the leaves of many deciduous and coniferous trees and woody shrubs. Adults have nonfunctional mouthparts and do not feed.

Adults have a ¾″ to 1⅞″ (20 to 47 mm) wingspan. They are highly variable in appearance seasonally, geographically, and between the sexes. Six separate species described in 1948 are now lumped together in this one species. The ground color is typically pale gray, buff, yellowish-brown, or brownish-yellow. A dark (melanic) form is sooty brown. A light form is whitish. Males have feathered (bipectinate) antennae. Females are larger than males and have thread-like antennae. They also have longer wings and the outer margins of the wings are more scalloped.

The wings are peppered, marked with black lines, and mottled with white, brown, and black. The discal spot is black. On the melanic form the ST line is brown contrasting with the darker brown ground color. On the forewing there is one or more pale spots near the midpoint of the subterminal (ST) line.

The caterpillar is up to 1⅜″ (3.5 cm) long. The ground color may be green, yellowish-green, gray, brick red, or brown. The pattern on mature caterpillars is subdued, with gray and reddish-brown mottling and faint streaking. There are no conspicuous bumps or swellings. There is usually a pale patch on the sides of the fifth abdominal segment (A5). There is often a pair of small pale spots on the upper side of A8.

Wingspan: ¾″ to 1⅞″ (20 to 47 mm)

Deciduous and mixed woodlands

Deciduous and coniferous trees and woody shrubs

One generation per year in Minnesota: June and July

Adults will come to lights.

Larvae overwinter on tree bark and on branches.

Deciduous and coniferous trees and woody shrub

Adults do not feed.

Sources

4, 21, 24, 29, 30, 71, 75, 82.

The genus Hypagyrtis has been shuffled from one tribe to another over the years. It was placed in the tribe Melanolophiini in 1948. It was moved to the massive tribe Boarmiini in 1977. In 1983 it was moved into the relatively small tribe Bistonini. In 1985 it was moved back into Boarmiini. BugGuide.net lists it in the tribe Bistonini. iNaturalist lists it in the tribe Boarmiini.

An article published in 2001, Molecular phylogeny, classification, biogeography and diversification patterns of a diverse group of moths (Geometridae: Boarmiini), mentions the genus just once, in the results: "Our analyses also show very well-supported clades, for instance … Hypagyrtis Hübner 1818".

This supports the placement of Hypagyrtis in the tribe Boarmiini.

Location: La Crescent, MN