Forest Tent Caterpillar

 Highlighted Species:

Forest Tent Caterpillar Malacosoma disstria (Lepidoptera: Lasiocampidae)

Image 1: Malacosoma disstria - Forest Tent Caterpillar Moth - Malacosoma disstria (Jo Ann Poe-McGavin, 2007)

About:

Wondering what penguins have to do with a caterpillar? Let’s take a closer look. The forest tent caterpillar (Malacosoma disstria) is a tent caterpillar in the family Lasiocampidae. As adults, they are furry, beige-brown moths. The species is found widespread across the United States and Canada, particularly to the East of the Mississippi River. These moths have one generation a year, and as adults live only 10-14 days after egg-laying. It is the larval, or caterpillar stage which gives this species the most recognition.

Image 2: Nat poses her nails on an oak leaf recently defoliated, such as the tent caterpillar might be seen doing (Naterpillar, 2025)

Tent caterpillars are known for mass-congregations and creating “tents” out of silk. After over-wintering in their egg mass and hatching in the spring, the forest tent caterpillar family spins a protective silk mat against the tree or branch where it feeds. In between feeding, it will rest and take shelter here. The congregation is safe from elements and temperature in their mat. They will feed on the foliage from maple, oak, aspen, and many more varieties of tree. The caterpillars will develop over several weeks and five instar stages before pupating. After 10 days, the adult will emerge– they will not feed, and will die shortly after mating.

Image 3: Is it a keyhole, a shoe print? No, it is clearly a penguin (Naterpillar, 2025)

Tent caterpillars are well renowned for their abilities to defoliate large areas of forest and urban landscapes when populations build over periods of 2-5 years. Natural enemies like flesh flies and birds will feed on these gregarious caterpillars, and naturally-occurring bacteria, viruses, and fungi will suppress caterpillar populations over time.

Design Notes:

While many field guides and resources will refer to the bright design on the caterpillar as “footprints” or “keyholes,” it was UMass Extension Entomologist Tawny Simisky where I first heard them described as “tiny penguins.” I find this a perfect description. Tawny is one of two mentors and colleagues who first encouraged me to pursue entomology– so this post is dedicated to her!

Image 4: This was a very fun and bold design to create (Naterpillar, 2025)

Resources:

Brandt, J. P. (2024). Forest tent caterpillar. Natural
Resources Canada.
https://tidcf.nrcan.gc.ca/en/insects/factsheet/9374 

Meeker, J. R. (2024, January 23). Forest Tent Caterpillar,
Malacosoma disstria Hübner (Insecta: Lepidoptera:
Lasiocampidae). Ask IFAS.
https://edis.ifas.ufl.edu/publication/IN341 

Poe-McGavin, J. A. (2007). Malacosoma disstria - Forest
Tent Caterpillar Moth - Malacosoma disstria.
BugGuide.net. photograph. Retrieved from
https://bugguide.net/node/view/113327/bgimage. 

University of Massachusetts Amherst. (2024, September
27). Malacosoma disstria. UMass Extension Landscape,
Nursery and Urban Forestry Program.

https://www.umass.edu/agriculture-food-environment/landscape/publications-resources/insect-mite-guide/malacosoma-disstria

Roundneck Sexton Beetle

 Highlighted Species:

Roundneck Sexton Beetle

Nicrophorus orbicollis

(Coleoptera: Silphidae)

Image: Roundneck sexton beetle (Nicrophorus orbicollis) with phoretic mites (Fry, 2020).

About:

The roundneck sexton beetle is a burying beetle in the Northeastern U.S. which has an important role breaking down carrion into nutrients. As the name burying beetle suggests, these beetles bury dead animals as a way to feed and raise their young. In the process, decomposing animal bodies are quickly processed back into the nutrient cycle both as food for the young beetles and for the many other organisms that will feed.

Image: Sexton beetles are common across Eastern North America, particularly where moist soil can be found (Naterpillar, 2024).

Nicrophorus orbicollis males will seek out carrion with highly sensitive antennae attuned to the odors of decay. The male will release pheromones to attract a female to the carrion as a way of courting her. Males will fight over this valuable commodity. If the female beetle accepts the gift, the two will dig a hole near the animal body and drag it down to bury it. Working quickly, burying beetles pass on fungus and bacteria to the decaying animal which aid in breaking down tissues. When secured, the female creates a brood chamber within and lays her egg. The buried dead animal will provide both food and shelter as it develops. 

Image: Nat's partner is incredibly supportive of her hobbies, even when he thinks taking pictures with roadkill is unpleasant (Naterpillar, 2024).

Sexton beetles exhibit some amount of parental care, as they will feed the growing larva on regurgitated carrion. Additionally, burying beetles have a mutualistic relationship with phoretic mites. These tiny red mites will ride on the backs of adult beetles, transporting them between sources of carrion. Once introduced to the buried animal, the mites defend against competitor insects like maggots and nematodes, leaving more food for the larval beetle.

Image: Please note, this decaying squirrel may not be representative of the actual stage of decay that sexton beetles prefer; it was simply the only carrion available then to pose with (Naterpillar, 2024).

As with many carrion-seeking insects, there is a specific window of time post-death which attracts them. Because of their reliable, innate sense to detect a corpse, burying beetles such as the roundneck sexton beetles are of forensic importance to humankind when a deceased person is found outside. Forensic succession is the order that various insects and other organisms will appear at a corpse By understanding insect biology, the time of death of a human body can be predicted by counting the species, life stage, and populations of insects present at a corpse. 

Design Notes:

    A black base with four bold patches of orange represent the roundneck sexton beetle. Although no phoretic mites can be seen, they will surely be picked up by my beetles at some point.

Image: the bold orange against black is a type of warning coloration (Naterpillar, 2024).

Resources:

Cannon, R. (2020, March 17). Phoresy: Mites hitchhiking on
burying beetles. Ray Cannon’s nature notes.
https://rcannon992.com/2020/03/15/
phoresy-mites-hitchhiking-on-burying-beetles/ 

Fry, R. (2020, July 25). Roundneck Sexton beetle (Nicrophorus      orbicollis). iNaturalist.     https://www.inaturalist.org/observations/54294351

Joseph, I., Mathew, D., Sathyan, P., & Vargheese, G.
(2011). The use of insects in forensic investigations:
An overview on the scope of forensic entomology.
Journal of Forensic Dental Sciences, 3(2), 89.
https://doi.org/10.4103/0975-1475.92154 

Roundneck Sexton beetle (Nicrophorus orbicollis).
JungleDragon. (n.d.). https://www.jungledragon.com
/specie/20290/roundneck_sexton_beetle.html 

White, P. S., Morran, L., & de Roode, J. (2017). Phoresy.
Current Biology, 27(12).
https://doi.org/10.1016/j.cub.2017.03.073

White Spotted Pine Sawyer

 Highlighted Species:

White Spotted Pine Sawyer
Monochamus scutellatus

(Coleoptera: Cerambycidae)

Image 1: A whitespotted pine sawyer adult on a tree. (B.witty 2012).

About:

The white-spotted pine sawyer is a large, shiny, black and white speckled longhorned beetle ranging across the U.S. and Canada. Adults seek weakened or dead coniferous trees, largely the eastern white pine (Pinus strobus) but includes other species of pines, firs, and spruce. The process of the larva growing, developing, exiting from the tree helps the break-down of the tree material. The galleries and exit holes allow for wood-decaying fungi and other insects to enter quickly and begin their recycling habits.

Image 2: Nat's pine sawyer nails, posed against a dead pine snag (Naterpillar, 2024).

The white-spotted pine sawyers have a two-year life cycle. After mating, the female chews a slit in the bark and deposits a white, oblong egg. The tiny larva emerges and begins to burrow into the tree, where it will chew and move throughout the layers of the tree creating galleries. The large, flattish grub will grow bigger and burrow deeper into the trunk where it overwinters. After a winter rest, it continues to eat and grow to full size before creating a pupation chamber, where it will once again overwinter. As temperatures warm into late spring and summer, the adult beetle emerges and chews its way out of the bark, exiting from a nearly perfectly circular hole in the bark. The adults will feed nearby on shoots and leaves, mating in the summer and continuing the cycle when a new egg is laid in the pine log.

Image 3: Just as in nature, these pine sawyer nails are drawn to a dead pine: the pine is being broken down by algae, fungi, and bacteria, and insect galleries can be seen. (Naterpillar 2024).

In spring when adult white-spotted pine sawyers emerge, one might confuse their sighting with that of an Asian Longhorned Beetle (Anoplophora glabripennis). Both are large, conspicuous black and speckled longhorned beetles. Unlike the white-spotted pine sawyer, the Asian longhorned beetle (ALB) is an introduced species. Primarily seeking out maples, elms, birches, poplars, willows and several more species, the ALB will choose healthy living trees for oviposition rather than dead and weak trees. Because of this, the many generations of larva growing and developing in a tree will eventually weaken and kill the tree, making the ALB an environmentally and economically important insect. 

Image 4: It's all about that white scutellum. (Naterpillar 2024).

The best way to tell a pine sawyer apart from an Asian Longhorned beetle is the white spot on the upper middle part of the wings, called a scutellum. As the name suggests, the white spotted pine sawyer will have a large white dot where the wing coverings meet together at the top. The ALB will not have this dot, and thus is an easy tell. Additionally, some context clues such as what type of tree (deciduous, coniferous) may be helpful to determine where it came from. For more information about the Asian Longhorned Beetle, you can visit the USDA APHIS website for details.

Design Notes:

To represent the pine sawyer, I started with a dark brown base. Adding black and white polka dots for the speckled coloration, and finally a large white “scutellum” at the top of my nails.

Resources:

Animal and Plant Health Inspection Service. (24 July
2024). Asian Longhorned Beetle. U.S. Department of
Agriculture.
https://www.aphis.usda.gov/plant-pests-diseases/alb

B. Witty. (5 May 2012). Whitespotted Sawyer -
Monochamus scutellatus [Photograph]. BugGuide.
https://bugguide.net/node/view/1103714

Natural Resources Canada. (27 October 2011).
Whitespotted sawyer. NRCan.
https://tidcf.nrcan.gc.ca/en/insects/factsheet/900

Wilson, Louis F. (June 1975). White Spotted Sawyer.
Forest Pest Leaflet. U.S. Department of Agriculture
Forest Service.
https://www.fs.usda.gov/foresthealth/docs/fidls/FIDL-7
4-WhiteSpottedSawyer.pdf

Monarch Caterpillar

 Highlighted Species:

Monarch Butterfly caterpillar
Danaus plexippus
(Lepidoptera: Nymphalidae)

Image 1: A well-developed caterpillar moves up and down the milkweed stalk looking for fresh leaves. (Naterpillar, 2024).

About:
A true icon, the monarch butterfly (Danaus plexippus) is one of North America’s most recognized insect species. Flashy orange and black wing patterns warn predators of its toxicity, gained from the milkweed plants it consumes as a caterpillar. Populations migrate between 1,000-3,000 miles each winter to a nesting site in northern Mexico. Thanks to national conservation efforts, their decimated population is back on the rise again.

Images 2-3: Nat poses her nails on healthy milkweed leaves. (Naterpillar, 2024).

The monarch butterfly migrates north during the summer, mating along the way. Up to four generations of butterflies may make this journey each year. After mating, the female lays several individually-placed round eggs on the underside of a milkweed (Asclepias spp.) leaf. Once hatched, the monarch caterpillar will eat milkweed leaves and molt several times, growing in size and gaining  characteristic bold stripes. 

Milkweed plants contain a type of cardiac glycoside called cardenolides, which act as a defense against predation. However, monarchs co-evolved with this plant and became able to consume and sequester these chemicals in their bodies, becoming toxic to predators themselves. Caterpillars may spend anywhere from 5 days to 2 weeks eating leaves before attaching to the underside of a milkweed leaf to make their chrysalis. Around late summer to early autumn, the last generation of butterflies will pupate and begin the migration back south. Their life span will be longer than all previous generations, allowing them to survive the trip.

Images 4-5: Nat poses the manicure next to a plump caterpillar. (Naterpillar, 2024).

Design Notes:

Do you think my monarch friend likes this homage? I chose to represent the irregular yellow, white, and black bands of a caterpillar who has already had several molts.

Resources:

MassAudubon. (2024). Monarch Butterflies. https://www.massaudubon.org/nature-wildlife/insects-arachnids/monarch-butterflies

Monarch Joint Venture. (2024). Life Cycle. https://monarchjointventure.org/monarch-biology/life-cycle

U.S. Forest Service. (2024). Monarch Butterfly Biology.
United States Department of Agriculture, United
States Forest Service. https://www.fs.usda.gov/wildflowers/pollinators/Monarch_Butterfly/biology/index.shtml