Clandestine dart

Hodges #

10926

Conservation Status

IUCN Red List

not listed

NatureServe

NNR - Unranked
SNR - Unranked

Minnesota

not listed

Description

Clandestine dart is a common and widespread, medium-sized moth. It occurs in the United States in the east from Maine to New Jersey, west to Illinois and Minnesota, and in the west from Washington State to southern California, east to North Dakota and New Mexico. It occurs across southern Canada and in the west north to Alaska.

Clandestine dart is found in mostly open areas, including old fields, gardens, and forest edges. The larvae are found on trees, shrubs, and herbaceous plants. They are a pest of a variety of crops, including apple, beans, blueberry, cabbage, corn, strawberry, and of trees, including pine and maple.

Adults are ⅞″ (22 mm) in length and have a 1½″ (38 mm) wingspan. Moth size is often given in terms of forewing length, which in this case is ⅝″ to ⅞″ (16 to 22 mm). The overall color is consistent, but the intensity is highly variable, ranging from light reddish brown to almost black.

The head and front of the thorax are shaded darker reddish brown. The first thoracic segment (prothorax) has a distinct line of white-tipped scales along the rear margin.

The forewings are long, relatively narrow, and dark brown, though in certain lighting they can appear blackish gray (sooty). They lack the black streaks common on most dart moths. The antemedial (AM) and postmedial (PM) lines are jagged and doubled, slightly paler inside with dark borders that end at the leading edge (costal margin) as a pair of dark spots. The lines are often obscure and sometimes completely absent, represented only by the dark spots on the costal margin. The large round spot near the AM line (orbicular spot) is the most distinct marking on the forewing. It is almond shaped, it has a dark border, and it is often connected to the less distinct kidney-shaped spot (reniform spot) by a bold black line.

The hindwing is dirty white in the middle and tinted brown toward the margins.

The mature caterpillar is pale brown and 1⅜″ to 1 9⁄16″ (35 to 40 mm) long. It has prominent, dark brown, wedge-shaped markings on each abdominal segment that form a conspicuous row of W-shaped marks. This is the feature that gives the caterpillar the common name W-marked cutworm.

Size

Total length: ⅞″ (22 mm)

Forewing length: ⅝″ to ⅞″ (16 to 22 mm)

Wingspan: about 1½″ (38 mm)

Similar Species

Habitat

Open areas, including old fields, gardens, and forest edges

Ecology

Season

Two generations per year: June through September

Behavior

Adults are active at night and will come to lights.

Life Cycle

Larva Food/Hosts

Leaves of trees, shrubs, and herbaceous plants

Adult Food

Flower nectar

Distribution

Sources

21, 24, 27, 30, 75, 82, 83.

Biodiversity occurrence data published by: Minnesota Biodiversity Atlas (accessed through the Minnesota Biodiversity Atlas Portal, bellatlas.umn.edu. Accessed 3/16/2026).

Spaelotis clandestina Harris, 1841 in GBIF Secretariat (2023). GBIF Backbone Taxonomy. Checklist dataset https://doi.org/10.15468/39omei accessed via GBIF.org. Accessed 3/16/2026.

Quinn, Edward. M., and Ron Danielson. April 27, 2009. A Survey of Lepidoptera in Three Priority Areas of the Minnesota State Parks System. https://files.dnr.state.mn.us/eco/nongame/projects/consgrant_reports/2009
/2009_quinn_danielson.pdf.