Spodoptera ornithogalli

(Guenée, 1852)

Yellow-striped Armyworm, Cotton Cutworm

is a noctuid widely distributed across the Americas, ranging from southern Canada through the United States, Mexico, Central America, and throughout much of South America. The is primarily known as a agricultural pest whose larvae feed on numerous crop plants. While occasionally damaging to soybean in the southeastern United States, it is generally considered a minor pest compared to other Spodoptera species. The larva is distinctive among armyworms for its relatively uniform black velvety appearance with contrasting bright yellow longitudinal stripes.

Spodoptera ornithogalli larva by Jacy Lucier. Used under a CC BY-SA 4.0 license.

Spodoptera ornithogalli 1 by Jacy Lucier. Used under a CC BY-SA 4.0 license.

Spodoptera ornithogalli on leaf by Frank Falconer. Used under a CC BY 4.0 license.

Pronunciation

How to pronounce Spodoptera ornithogalli: /ˌspoʊ.dəˈtɝː.ə ɔrˌnɪθ.oʊˈɡæ.laɪ/

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Identification

are distinguished from the similar by their darker body coloration and sharper markings. Larvae are distinguished from other Spodoptera by their uniform black velvety appearance with bright yellow longitudinal stripes that are not interrupted by the black spots. Unlike (S. frugiperda), larvae lack the pronounced inverted white Y-shaped mark on the and the distinctive pinaculae arrangement. Unlike southern (S. eridania) and black armyworm (S. cosmioides), larvae lack the complex pattern of black markings on the and first abdominal segment.

Images

Habitat

Agricultural fields, particularly soybean, cotton, and vegetable crops. Larvae are often found in double-crop fields with small plants planted after wheat. The occupies a broad range of across its extensive geographic distribution.

Distribution

North America: Canada (Ontario, Quebec), United States (widespread from California to Florida, east to Kansas), Mexico. Central America and Caribbean: Antigua and Barbuda, Bermuda, Rica, Cuba, Dominica, Dominican Republic, El Salvador, Guatemala, Honduras, Jamaica, Puerto Rico. South America: Argentina, Bolivia, Brazil (Acre, Bahia, Federal District, Espírito Santo, Mato Grosso, Mato Grosso do Sul, Pará, Paraná, Rio Grande do Sul, Roraima, Tocantins), Colombia, Ecuador, French Guiana, Peru, Suriname, Venezuela. The has been intercepted at ports in Europe (Denmark) and Asia (Japan) but is not established there.

Seasonality

are on wing from April to November depending on location. Multiple occur per year in warmer regions.

Diet

Larvae are highly , feeding on numerous crops including alfalfa, asparagus, bean, beet, cabbage, clover, maize/corn, cotton, cucumber, hops, grape, grass, jimsonweed, morning glory, onion, pea, peach, peanut, potato, sorghum, soybean, sunflower, sweet potato, Swiss chard, tobacco, tomato, turnip, wheat, watermelon, and wild onion. Also feeds on ornamentals including chrysanthemum and roses, and weeds including Amaranthus retroflexus, Chenopodium album, Datura stramonium, Erigeron canadensis, Plantago lanceolata, and Rumex.

Host Associations

Glycine max - pestOccasional pest of soybean, primarily in southeastern U.S. and in double-crop fields
Gossypium hirsutum - pestKnown as cotton
Zea mays - pestFeeds on maize/corn
Nicotiana tabacum - pestFeeds on tobacco
Solanum lycopersicum - pestFeeds on tomato
Asparagus officinalis - pestRepeated port interceptions on asparagus shipments to Europe
Trifolium repens - food plant observed on white clover

Life Cycle

Complete with , larva, pupa, and stages. Multiple per year in suitable climates.

Behavior

Larvae feed primarily on foliage. In soybean, larvae are often encountered in low numbers but can reach pest status in double-crop fields with small plants planted after wheat, similar to . When abundant, larvae can damage seedlings by cutting them off at ground level and later stages by feeding on foliage.

Ecological Role

Herbivore and occasional agricultural pest. Larvae function as primary consumers in agricultural . The serves as prey for various including predatory stink bugs such as Podisus maculiventris.

Human Relevance

Agricultural pest of moderate importance, particularly in the southeastern United States. Known as cotton due to damage to cotton. Repeated port interceptions on asparagus shipments to Europe have raised phytosanitary concerns. Not considered among the most economically important Spodoptera compared to (S. frugiperda) or southern (S. eridania) in South America.

Similar Taxa

Spodoptera littoralisOriginally confused with S. ornithogalli due to very similar forms; distinguished by S. littoralis having lighter body coloration and less sharp markings
Spodoptera frugiperdaLarvae distinguished by presence of inverted white Y-shaped mark on and distinctive pinaculae arrangement on abdominal segments
Spodoptera eridaniaLarvae distinguished by presence of black marking on and interrupted subspiracular line; S. ornithogalli lacks these features and has more uniform coloration
Spodoptera cosmioidesLarvae distinguished by presence of dark spot on and different pattern of black markings on abdominal segments

More Details

Historical Taxonomic Confusion

When first discovered, this was thought to be the American representative of due to their very similar forms.

Phytosanitary Interceptions

Repeated port interceptions occurred throughout 2020, especially on consignments of asparagus from the Americas, leading to detection in Denmark and Japan though the remains absent from established European and Asian .