Tent caterpillar moths and lappet moths are medium-sized, with thick, long scales that make them look furry. The abdomen generally extends past the tips of the wings when they are folded back over the body. Most are shades of brown, tan, or gray, with camouflage markings that help them blend in with tree bark or other natural surfaces. Both males and females have feathery antennae. On either side of the mouth, fingerlike labial palps project forward, and the strawlike proboscis is undeveloped or missing entirely; adults do not feed. The females are like males in color and pattern, but they are considerably larger, with broader wings, and they are usually rather weak fliers.
The caterpillars are very hairy, colorful, and striped lengthwise. In several species in this family, the larvae build communal webby “tents” in trees and shrubs using silk that they spin. They leave the tent to feed on leaves of the host tree or other nearby trees. The larvae of some species may live in groups but not build a “tent.”
Examples of Missouri’s lasiocampids include the eastern tent caterpillar (Malacosoma americanum), forest tent caterpillar (M. disstria), and large tolype (Tolype velleda). The American lappet moth (Phyllodesma americana), with its wavy-edged, gray and rust-colored wings, looks like a small dead leaf.
Lasiocampids are sometimes called “snout moths” because of mouthparts that protrude forward from the head. Crambids and pyralid moths are also called “snout moths” for the same reason.
Habitat and Conservation
Some species, such as the eastern tent caterpillar, can be destructive pests of woodland, orchard, or landscaping trees.
As with all hairy caterpillars, use caution before handling. The hairs of some species may be skin-irritating, and some people may be more sensitive to the toxins than others.
What's a "lappet"? Lasiocampids are sometimes called “lappet moths” because of a skin flap that hangs over the prolegs (the mid-body, abdominal legs) — a “lappet” is a decorative hanging flap of cloth; pairs of these used to be popular on hats. King Tut’s striped headcloth had them, and Catholic and Episcopal mitres have scarflike lappets attached. In previous centuries, women’s hats often had lacy lappets that descended in front of one’s shoulders.
Much like silkworms (which are in a different family), some lasiocampid species have been used for making fabric. Unlike the silk of silkworms — which is carefully unwoven from the cocoon as a single thread — lasiocampid silk is carded and spun. A famous example is “borocera” silk from Madagascar, where women’s cooperatives use techniques handed down for generations. Their scarves and shawls, called lambas, are an important cultural tradition. People wear them in all parts of life, even as the traditional burial shroud. Handmade borocera or “landibe” textiles are now chic, fair-trade fashion accessories in the West.
Lasiocampid caterpillars serve as a limit on the growth of the plants they eat. A wide variety of predators — ranging from tiny parasitoids, mantises, and spiders to birds, bats, reptiles, amphibians, skunks, armadillos, and more — may feed on the eggs, caterpillars, pupae, and adult moths.
In Madagascar, the tapia food trees of lasiocampid silk-making caterpillars have been declining due to overharvest and deforestation, but environmental efforts have helped stabilize their populations, and those of the silk-making caterpillars. So, protecting the silk industry is protecting the forest ecology, and vice versa.