Slug moths are famous for their distinctive larval stage. Unlike typical caterpillars, slug moth larvae often resemble slugs, boasting flattened bodies and a variety of vivid colors and spiny projections that serve as a defense mechanism against predators. Join me to discover 14 different types of slug moths, each with its own unique characteristics and adaptations.
Table of Contents
Saddleback caterpillar moth (Acharia stimulea)
The Saddleback caterpillar moth is one of the most highlighted slug moth types. This species is commonly known for its caterpillar stage with its distinctively bright color patterns and urticating spines that deter predators. These spines can cause a painful sting and leave a rash on humans who touch them.
The adult moth is dark brown with black shading and has a glossy appearance. It has a small white spot near the forewing base and one to three more near the apex. The moth is found in the eastern United States, from Massachusetts to Florida, and west to eastern Missouri and Texas.
Skiff moth (Prolimacodes badia)
The next type of slug moth is the skiff moth. This insect is primarily found in North America from New Hampshire to Florida, extending westward to southern Ontario.
Like the saddleback caterpillar above, the larvae of the skiff moth are also distinctive, resembling an overturned boat (skiff) due to its humped body with two ridges and a short tail. They feed on a variety of trees and shrubs such as birch, blueberry, cherry, chestnut, oak, and willow. While the skiff moth is not known to sting, it spins a silk cocoon to overwinter before emerging as a moth in the following season.
The adult moth is gray to beige with dark brown markings on the wings and has a tuft of setae on the thorax. It has a wingspan ranging from 24 to 35 mm and is active from May to September.
Hag moth (Phobetron pithecium)
The hag moth is a native species found in shrubby fields and deciduous forests in the eastern half of the United States. It is stout and furry, with males having transparent patches on their wings and females mimicking bees with large tufts of hair on their legs.
The caterpillar of this slug moth type known as the “monkey slug,” has a unique appearance with multiple pairs of fleshy appendages on its sides, which are not used for movement. These appendages are covered with short, brown hairs and tufts of short, stout hollow spines that connect to toxin glands in the skin. To know more about this hag moth, you can check here.
Jewel-tailed slug moth (Packardia geminata)
This jewel-tailed slug moth is a small type of slug moth that is found across the United States, Canada, and Mexico. It has light to medium brown wings with a distinctive cluster of white dots resembling a strand of pearls. The caterpillar of this moth has a slug-like appearance, with a wide, oval-shaped green body and a raised ridge on its back. The larvae feed on trees such as birch, hickory, oak, and spruce. As members of the slug moth family, the caterpillars tunnel through the interior of tree trunks and emerge as adults when ready to pupate on the ground.
Spiny oak-slug moth (Euclea delphinii)
The next slug moth type is the spiny oak-slug moth. It is characterized by its distinctive appearance, with brown forewings featuring minty green patches and dark brown patches. The hindwings are brown, and the body is brown. The caterpillars are wide and flat, with rows of yellow or orange stinging spines that run along their bodies. These spines contain venom and are used for defense against predators.
The moths are nocturnal and attracted to lights at night. They are found in deciduous forests and feed on the leaves of various tree species, including oak, willow, and cherry. The species is widespread across North America, with multiple generations in some regions
Nason’s slug moth (Natada nasoni)
The Nason’s slug moth lives in North America, with a range spanning from Maine to Florida, west to Missouri and Mississippi. The adult moths have yellowish-tan forewings with heavy brown shading, and their wingspan ranges from 1.6 to 2.9 cm.
The larvae are green, oval-shaped, and have a distinctive appearance. They have a central row of white markings resembling spades, a raised yellow ridge along the sides, and red-orange bumps with short spines that can cause pain and leave redness on skin.
They feed on the leaves of various tree species, including beech, chestnut, hickory, and hornbeam. The moths are active from June to August, and their life cycle involves multiple generations per year.
Pin-striped slug moth (Monoleuca semifascia)
The pin-striped slug moth is found in northern barren land and southern dry woodlands. You can find these species in New York, Texas, New Jersey, Kansas, Florida, and Missouri.
The adult pin-striped slug moth has brown, sometimes reddish brown color, with a narrow, wavy, silvery white to yellowish line above the inner margin. Its larvae are peach colored with wavy, bright reddish-orange, black, or dark brown vertical striping in three sequences of a four-stripe pattern. The bright reddish-orange stripes are covered with numerous white, stinging hairs.
Yellow-shouldered slug (Lithacodes fasciola)
The yellow-shouldered slug, also known as the ochre-winged hag moth, is distinguished by its long Y-shaped horn, which it uses to fight other males. It has ochre-colored wings with a yellow shoulder patch, giving it its common name. The insect has a wingspan of about 25-30mm. Its larvae are approximately 1/2 inch (1.3 cm) long. They are translucent and have bright colors, often appearing like jewels.
Stinging rose caterpillar moth (Parasa indetermina)
Among different types of slug moths, the Stinging rose caterpillar moth is one of the most beautiful types, both the adults and caterpillars. The adult moths have a brown forewing with a large green patch and rounded outer edge, and a yellowish hindwing with a narrow brown border.
On the other hand, its larvae are brightly colored with blue, orange, and white stripes, and have six pairs of large tubercles along the dorsal surface. These tubercles are covered with hollow spines with detachable tips that contain toxins to ward off predators. These toxins can cause skin irritation in humans.
These moths are found in the eastern United States, from New York to Florida and west to Missouri and Texas. They live in sandy, pine-oak savannahs of the southern Atlantic Coastal Plain, and in maritime dunes and maritime grasslands.
Spun glass slug moth (Isochaetes beutenmuelleri)
The Spun glass slug moth is a type of slug moth family. It is found in the United States, from southeastern New York to Florida, and west to Missouri and Mississipp.
The adult moths have a yellowish color with vague orange-brown lines and shading on their forewings, with a circular brown spot at the midpoint between the posterior and subterminal margins. The wing span ranges from 1.9 to 2.4 cm.
Its caterpillar is oval or oblong and is a frosty, mint green color. It has nearly transparent extensions growing from their bodies, which are covered in fine hairs that create a glassy, snowflake-like fragility. This appearance is reminiscent of spun glass, hence the name “Spun Glass Slug Moth.
Purple-crested slug moth (Adoneta spinuloides)
Next is the purple-crested slug moth. This species has distinct features in its adult and larval stages. The adult of this moth has a brown color, with the forewings having dark brown with black veins and a median streak. The hindwings are lighter with almost no patterns.
This species is found in various regions, ranging from New Hampshire and Quebec to North Carolina, west to Missouri and Mississippi, and possibly extending to Florida. It feeds on a variety of trees and shrubs, including beeches, birches, chestnuts, linden, Prunus species, and willows.
Crowned slug moth (Isa textula)
Like most slug moth types, the crowned slug moth is brown. It has inconspicuous gray shading. There are no prominent markings. Its wingspan ranges from 1.7 to 2.5 cm.
The crowned slug caterpillar has a flattened, oval-shaped body with a pastel green color. It is adorned with plumes of stinging hairs around the perimeter and shorter, less conspicuous stinging hairs on its back. Two pale lines run down its back, terminating in a pair of “horns” on the front and a pair of stinging plumes on the rear. Some individuals have small, red dots on their backs and red markings on the front edge.
Red-eyed button slug moth (Heterogenea shurtleffi)
As the name suggests, the red-eyed button slug moth is characterized by its distinctive red eyes and button-like appearance. You can differentiate males from females due to their colors. Females have cinnamon to brown forewings, while males have darker chocolate brown forewings. Hindwings are generally lighter brown in females and blackish in males. The antennae are threadlike, with the males’ antennae slightly wider than those of the females.
The caterpillar of this species is lime green overall, with a characteristic coat of arms-shaped marking (D marking) on the dorsum that is bordered in brown or red, frequently with a yellow border. The mature caterpillar reaches roughly 6-10 mm in length and goes through seven instars.
The species is found in North America, with specific records in the United States, including Tennessee, North Carolina, Georgia, Virginia, Florida, Maryland, and Mississippi.
Packard’s white flannel moth (Alarodia slossoniae)
Last but not least, the Packard’s white flannel moth. Unlike other slug moth types, this species has a distinctive white coloration with a flannel-like appearance on its forewings.
The caterpillar of this insect is yellow in its early instars, gradually becoming pale greenish white to white in later instars. Its body is covered in a thick coating of fur-like setae (hairs), which are predominantly orange on the thorax. The antennae of the caterpillar are comb-like with teeth on two sides, with the rami of males being longer than those of females.
These larvae eat various host plants, including elm, blackberry, raspberry, apple, oak, and other trees and shrubs. Packard’s white flannel moth is typically found in scrub habitats, in North America, specifically in the United States.
