Mournful Duskywing (Erynnis tristis) is a small-medium butterfly, with a wingspan of 1.25 to 2 inches. It can be seen in our local area from the last week of March through the first week of October. Numbers are fairly uniform through most of this period. Host plants are various Oaks. Females lay eggs only on young, tender growth. So Coast Live Oak (Quercus agrifolia) and Blue Oak (Q. douglasii) are used only in the spring, whereas Valley Oak (Q. lobata), which grows all summer, is used all season.
This is an example of a Spread-wing Skipper. Unlike Grass Skippers, the forewing and hindwing are laid out side-by-side.
In the US, it is found from Northern California south to San Diego, and through central Arizona, southern New Mexico to the Lower Rio Grande Valley. It is also seen in the mountains of Mexico, and through Central America to Colombia.
Thi butterfly was added to the Garden’s species list only in July 2024.
