10 Biggest Beetle Families in North America

Beetles (Order Coleoptera) account for 25% of the animals living on Earth, with roughly 350,000 known species described to date. An estimated 30,000 species of beetles inhabit the U.S. and Canada alone. How do you even begin to learn to identify beetles, when this order is so large and diverse?

Start with the 10 biggest beetle families in North America (north of Mexico). These 10 beetle families account for nearly 70% of all beetles north of the U.S. and Mexico border. If you learn to recognize members of these 10 families, you will have a much better chance of identifying beetle species you encounter.

Here are the 10 biggest beetle families in the U.S. and Canada, from largest to smallest. The species numbers in this article refer to the population in North America, north of Mexico, only.

Rove beetle adult.
Rove beetles have short elytra, leaving the abdomen largely exposed. Susan Ellis, Bugwood.org

It might surprise you to learn there are well over 4,100 known species of rove beetles in North America. They typically inhabit decaying organic matter, like carrion and dung. Rove beetles have elongate bodies, and the elytra are usually only as long as the beetle is wide. The abdomen is mostly visible, since the elytra don't extend far enough to cover it. Rove beetles move quickly, whether running or flying, and sometimes raise their abdomens in the manner of scorpions. More »

02
of 10

Snout Beetles and True Weevils (Family Curculionidae)

Palmetto weevil.
A weevil has a well-developed snout. Matt edmonds at en.wikipedia (CC by SA license)

Most members of this family bear a well-developed snout, with antennae projecting from it. Almost all of the more than 3,000 species of snout beetles and true weevils feed on plants. Some are considered significant pests. When threatened, snout beetles will often drop to the ground and remain still, a behavior known as thanatosis.

Murky ground beetle.
Most ground beetles are shiny and dark. Whitney Cranshaw, Colorado State University, Bugwood.org

With over 2,600 North American species in this family, the ground beetles deserve your attention. Most Carabid beetles are shiny and dark, and many have grooved or ridged elytra. Ground beetles run quickly, preferring to flee on foot than to fly. Their speed also serves them well when hunting prey. Within this family, you'll encounter some interesting groups, like the exploding bombardier beetles and the colorful tiger beetles.  More »

04
of 10

Leaf Beetles (Family Chrysomelidae)

Larger elm leaf beetle.
Leaf beetles are often colorful. Gerald J. Lenhard, Louisiana State University, Bugwood.org

About 2,000 leaf beetles are munching away at North American plants. The adult leaf beetles tend to be small to medium in size, and can be quite colorful. Though adults generally eat either foliage or flowers, leaf beetle larvae may be leaf miners, root feeders, stem borers, or even seed eaters, depending on the species. This large family is subdivided into 9 smaller subfamilies.

Green June beetle.
A June beetle, one of the subgroups of scarab beetles. © Debbie Hadley, WILD Jersey

There's a lot of variation among the roughly 1,400 species of scarab beetles living in the U.S. and Canada, but generally they are robust, convex beetles. Scarab beetles fill almost every ecological role, from disposing of dung to feeding on fungi. The family Scarabaeidae is subdivided into a number of subfamily groups, including dung beetles, June beetles, rhinoceros beetles, flower beetles, and others. More »

Clown beetle.
Darkling beetles look similar to ground beetles. Whitney Cranshaw, Colorado State University, Bugwood.org

Darkling beetles can be easily misidentified as ground beetles, so examine the specimens you collect or photograph closely. This family numbers well over 1,000 species in North America, but most live in the western half of the continent. Darkling beetles are mostly vegetarian, and some are pests of stored grains. Tenebrionid larvae are commonly called mealworms.  More »

Asian longhorned beetle.
The exotic Asian longhorned beetle traveled to North America in wooden packing crates. Photo: Pennsylvania Department of Conservation and Natural Resources - Forestry Archive, Bugwood.org

All of the 900 or so long-horned beetles in the U.S. and Canada feed on plants. These beetles, which range in length from just a few millimeters to 6 centimeters, usually bear long antennae – thus the common name long-horned beetles. Some are brilliantly colored. In many species the larvae are wood-borers, so they may be considered forest pests. Exotic species (like the Asian longhorned beetle) sometimes invade new territory when the boring larvae stow away in wooden packing crates or pallets.  More »

Eyed click beetle.
An eyed click beetle, one of the largest species in this family. Photo: Gerald J. Lenhard, Louiana State Univ, Bugwood.org

Click beetles get their name from the clicking sound they make when they jump to escape predators. They're typically black or brown, but can be identified by the shape of the pronotum, the corners of which extend backward like spines to embrace the elytra. Click beetles feed on plants as adults. Just fewer than 1,000 species of click beetles inhabit the entire Nearctic region. More »

Metallic wood-boring beetle.
Metallic wood-boring beetles can often be recognized by their characteristic bullet shape. Scott Tunnock, USDA Forest Service, Bugwood.org

You can usually recognize a metallic wood-boring beetle by its characteristic bullet-shaped body. Most come in metallic shades of green, blue, copper, or black, which is why they're often called jewel beetles. Buprestid beetles make their living in wood, and their larvae can cause significant damage to or even kill living trees. There are over 750 Buprestid species living in North America, the most famous of which may be the exotic, invasive emerald ash borer. More »

Lady beetle.
Nearly all lady beetles are beneficial predators. Whitney Cranshaw, Colorado State University, Bugwood.org

Nearly all of the 475 North American species of lady beetles are beneficial predators of soft-bodied insects. You'll find them wherever aphids are plentiful, happily feasting and depositing eggs. Gardeners might consider the Mexican bean beetle and the squash beetle the black sheep of the otherwise beloved lady beetle family. These two pest species do considerable damage to garden crops.

 

Sources:

•    Borror and DeLong's Introduction to the Study of Insects, 7th edition, by Charles A. Triplehorn and Norman F. Johnson.
•    Coleoptera – Beetles/Weevils, Dr. John Meyer, North Carolina State University. Accessed online January 7, 2014.
More »

Format
mla apa chicago
Your Citation
Hadley, Debbie. "10 Biggest Beetle Families in North America." ThoughtCo, Mar. 3, 2017, thoughtco.com/biggest-beetle-families-in-north-america-1968153. Hadley, Debbie. (2017, March 3). 10 Biggest Beetle Families in North America. Retrieved from https://www.thoughtco.com/biggest-beetle-families-in-north-america-1968153 Hadley, Debbie. "10 Biggest Beetle Families in North America." ThoughtCo. https://www.thoughtco.com/biggest-beetle-families-in-north-america-1968153 (accessed January 23, 2018).