gray half-spot

not listed

NNR - Unranked

SNR - Unranked

not listed

Gray half-spot is a common, native, small to medium-sized moth. It occurs in the United States and Southern Canada east of the Great Plains. It is most common in the northeast, less common in Minnesota, where it reaches the western extent of its range. Adults are found from early May to early October in Minnesota in a variety of habitats, including woodlands, fields, and gardens. The larvae feed exclusively on the foliage of several species of St. Johnswort.

Adults are ⅝″to 1″ (15 to 25 mm) in length and have a 1⅛″to 1⅞″ (28 to 48 mm) wingspan.

The forewings are light gray with heavy, longitudinal, brown and black streaking. There is a long dash in the basal area and a shorter dash in the sub-basal area. The circular spot in the upper median area (orbicular spot) is an elongated oval, brown in the center, surrounded by white, and bordered with a thin black line. The kidney-shaped spot in the lower median area (reniform spot) is mostly pale with some brown and black in the center. The bottom of the orbicular spot is fused to the top of the reniform spot. A blackish, wedge-shaped patch extends from the antemedial area through the postmedial area and surrounds the inner half of the reniform spot. This is the feature that gives the moth its common name. There are black longitudinal streaks in the subterminal area. Below the wedge-shaped mark, these are bordered by a slanted white line. In the terminal area there is a crescent-shaped mark separating all of the veins.

The caterpillar is reddish brown with a pale stripe on each side below the breathing pores (spiracles).

Total length: ⅝″to 1″ (15 to 25 mm)

Wingspan: 1⅛″to 1⅞″(28 to 48 mm)

A variety of habitats, including woodlands, fields, and gardens

Two generations per year: early May to early October

The larvae remain on plant foliage during the day.

Pupae overwinter

St. Johnswort

Flower nectar

Sources

4, 21, 24, 29, 30, 71, 75, 82, 83.

Common

This species was first described as Cloantha ramosula in 1852. It was moved to the genus Actinotia in 1875, then to the genus Delta in 1909. A study of the North American Delta species (Clarke, 1940), citing differences between the North American species and the one found in Madagascar, moved all of the North American species to the new genus Nedra.

Location: Lake Shore