American Lady Caterpillar or Painted Lady Caterpillar
Scientific Name: Likely Vanessa virginiensis (American Lady Butterfly) or Vanessa cardui (Painted Lady Butterfly) caterpillar. Distinguishing between the two from this image alone is difficult, as their caterpillars are very similar.
Order & Family: Order: Lepidoptera, Family: Nymphalidae (Brush-footed Butterflies)
Size: Caterpillars typically range from 2.5 to 3.5 cm (1 to 1.4 inches) in length when fully grown.
Natural Habitat
They are found in a wide range of habitats where their host plants grow, including meadows, fields, gardens, roadsides, and open woodlands.
Diet & Feeding
The caterpillars are herbivorous, feeding on the foliage of various plants. Common host plants include composites (Asteraceae) like thistles, everlasting, and nettles. The image suggests it is on a yellow flower, which could be a type of composite.
Behavior Patterns
These caterpillars are known for their distinctive spiny appearance. They feed on a variety of plants, often moving slowly across leaves. When disturbed, they may twitch or drop to the ground. They undergo complete metamorphosis, forming a chrysalis (pupa) from which the adult butterfly emerges.
Risks & Benefits
Generally, these caterpillars pose no direct risk to humans. Their spines are not typically venomous, though some individuals might experience mild irritation from contact. They are beneficial as pollinators (in their adult butterfly stage) and serve as a food source for other animals in the ecosystem. As caterpillars, they are primary consumers in the food web.
Identified on: 8/10/2025