The Lasiocampidae are a family of moths also known as eggars, tent caterpillars, snout moths (although this also refers to the Pyralidae), or lappet moths. Over 2,000 species occur worldwide, and probably not all have been named or studied. It is the sole family in superfamily Lasiocampoidea.

Etymology: Their common name "snout moths" comes from the unique protruding mouth parts of some species which resemble a large nose. They are called "lappet moths" due to the decorative skin flaps found on the caterpillar´s prolegs. The name "eggars" comes from the neat egg-shaped cocoons of some species. The scientific name is from the Greek ´ (wooly) and ´ (caterpillar).

 Caterpillars of this family are large and are most often hairy, especially on their sides. Most have skin flaps on their prolegs and a pair of dorsal glands on their abdomens. They feed on leaves of many different trees and shrubs, and often use these same plants to camouflage their cocoons. Some species are called tent caterpillars due to their habit of living together in nests spun of silk.

As adults, the moths in this family are large bodied with broad wings and may still have the characteristic elongated mouth parts, or have reduced mouthparts and not feed as adults. They are either diurnal or nocturnal. Females lay a large number of eggs which are flat in appearance and either smooth or slightly pitted. In tent caterpillars, the eggs are deposited in masses and covered with a material that hardens in air. Females are generally larger and slower than the males, but the sexes otherwise resemble each other. Moths are typically brown or grey, with hairy legs and bodies.

Subfamilies and tribes: Subfamily Chionopsychinae (1 genus, 2 species)

Subfamily Chondrosteginae (2 genera)

Subfamily Lasiocampinae (130 genera)

• Tribe Gastropachini (previously subfamily Gastropachinae)
• Tribe Lasiocampini
• Tribe Malacosomatini

Subfamily Macromphaliinae (15 genera)

Subfamily Poecilocampinae (about 20 genera)

e.g. Poecilocampa Stephens, 1828, Labedera Walker, 1855

Else, Other genera incertae sedis

• Bhima
• Borocera
• Nesara

Selected North American species: 

• American lappet moth, Phyllodesma americana
• Riley´s lappet moth, Heteropacha rileyana
• Eastern tent caterpillar, Malacosoma americanum
• Forest tent caterpillar, Malacosoma disstrium
• Western tent caterpillar, Malacosoma californicum
• Larch moth, Tolype laricis
• Velleda lappet moth, or large tolype Tolype velleda