Litter moths are a subfamily of rather nondescript brownish moths, often with intricate patterns that camouflage them as they rest on tree bark or among leaf litter on the forest floor. A few species are nearly white. Identifying the various species usually involves the patterns on the wings but may also require examination of the mouthparts.
There are more than 75 species in this subfamily in North America north of Mexico.
The litter moths used to be a subfamily in the formerly large noctuid family (owlet moths), and in the past they have been placed in their own family.
They hold their wings flat and to the sides, giving them a triangular shape when seen from above. Males often have palps (mouthparts) that they extend in front of their heads.
Adult length: less than 1 inch (varies with species).
Statewide. Different species may have different distributions.
Habitat and Conservation
These are not the most colorful moths, nor are they spectacularly large, so people often overlook or disregard them. As you shuffle amid leaf litter in the woods, you may see these moths flutter up and away from you. You might also see individuals near porchlights, since they are attracted to lights at night.
The larvae of this subfamily are mostly true to their name: many eat decaying or dead leaves, but various members of this group may eat living vegetation, flowers, and fruit. As with many other insects, different species of plant-eaters often have certain types of plants they eat.
The new family (Erebidae) that the litter moth subfamily now belongs to joins together several additional moth groups. As with the litter moths, many of these, such as the underwing moths, used to be members of the formerly huge family Noctuidae. The noctuid family continues, but minus those groups. Meanwhile, the tiger and lichen moths, and the tussock moths, which used to have their own families, are now reduced to subfamilies, alongside the litter moths, in the new family Erebidae. These recent taxonomy revisions are confusing, but they represent a much greater clarity in our understanding of the true relationships among these animal groups.
Eggs hatch into caterpillars, which eat and grow and molt. When the caterpillars are fully grown, they pupate and become adult moths.
It's easy to overlook the importance of these fragile, rather boring insects, but if you like other parts of nature, such as birds and flowers, you should keep in mind the importance of each component of nature. Birds feed insects like these to their nestlings, and flowers benefit from rich soils built up by a host of tiny decomposers, including litter moth caterpillars.
The caterpillars that eat dead or decomposing leaves aid in the decomposition process, converting debris into fertile soil that can be used by living plants. All of these humble moths (and their caterpillars and defenseless pupae) serve as food for a wide variety of insectivores, including spiders, dragonflies, robber flies, assassin bugs, toads, frogs, lizards, snakes, birds, bats, shrews, mice, and many more animals.