The Japanese common grass yellow is a small East Asian butterfly with bright yellow wings edged in black. It doesn't occur in the US; it lives in Japan, Korea, Taiwan, and eastern China, where adults survive the winter and fly again in early spring.
Appearance
- Appearance
- Yellow wings with black outer borders; males are a deeper yellow than females. The underside has brown spots.
- Seasonal forms
- Summer adults have wide black borders; autumn adults have narrow borders or almost none.
Where it lives
- Typical habitats
- Grasslands
- Field edges
- Roadsides
- City parks
- Range
- Japan (Honshu south to the Nansei Islands), Korea, Taiwan, and eastern China. It is not found in North America.
Behavior
- Overwintering
- Overwinters as an adult butterfly.
Life cycle
- Caterpillar food plants
- Caterpillars feed on plants in the pea family, such as silk tree and bush clovers in Japan.
Name and classification
- About the name
- It used to be treated as part of the common grass yellow (Eurema hecabe), a widespread tropical species. The two are now treated as separate species: where they meet in the far south of Japan, they don't interbreed and use different host plants.
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