Owlet Moth (Mesogona olivata)

By Kelly Rourke, Pollinator Partnership

Alkali Bee.
Owlet Moth (Mesogona olivata). Photo by Gary McDonald, 2008 San Benito County, California. CalPhotos.

Map of the United States showing states. Blue dots on the map indicate where the species may be found.
Distribution of Mesogona olivata. Courtesy Moth Photographers Group.

Despite this particular moth’s adaptive ability to blend in, it stands out as an important pollinator. There have been recent discoveries that have resulted in some changes in the taxonomy of this species. It is considered the “Old World” species of Pseudoglaea (genus), which is often used synonymously with the genotype Mesogona. Until recently, Owlet moths were placed in the family Noctuidae and they are still commonly referred to as, and grouped with, noctuid moths. There are five species in the Mesogona genus, two in Eurasia, and three in North America. Mesogona olviata was more recently discovered with observations in Oregon and Washington.

Mesogona olivata prefers wet forest to semi-arid steppe habitats. Geographically, this speciesis most commonly found along the west coast of North America from British Columbia to California. It also occurs eastward to Colorado, Wyoming, and Texas. It is thought to likely be found in northern Mexico as well; however, this is not strongly documented. Individuals from semi-desert locales tend to be pale while those from more mesic forests are darker. This species can be found from 10 feet to 7,087 feet in elevation. It is a nocturnal moth and is attracted to lights and sugar baits.

Coloration is variable depending on location. Forewings can be gray-brown, red-brown, or light yellow-brown, with a design of smooth lines and spots. The forewings are 15 to 20 millimeters in length and two times as long as wide. The hindwings are always gray, even in its most pale form. Its long “tarsal claws” or first legs most easily identify Mesogona olviata.

The other two North American species are Mesogona rubra and Mesogona subcuprea. Mesogona rubra has a more reddish hue and Mesogona subcuprea has a lighter, tan coloration. Both other species have shinier and more colorful hindwings. Mesogona olviata is sympatric with both other species.

Adult moths are most active and lay their eggs in the fall when foliage is changing color. The larvae hatch in the spring feeding on a variety of woody plants. Larval food plants include poplar, oak, hazel, alder, and antelope brush. Moth coloring often resembles the bark of the food plant it prefers. This is most likely a protective adaptation.

Additional Resources

Pollinator of the Month

Sulphur Butterfly (Phoebis sennae)
Cloudless Sulphur Butterfly (Phoebis sennae)