12 Types of Beetles in Maryland: Identification, Habitat, and Garden Impact
October 30, 2026
Beetles hold more described species than any other insect order, roughly 40 percent of known insects. Maryland gets its full share of them, from metallic hunters on forest trails to red milkweed specialists in roadside meadows.
The types of beetles in Maryland vary as much as the state’s terrain, which runs from Chesapeake Bay shoreline through the Piedmont to the Appalachian ridges in the west. BeetleIdentification.org’s Maryland database alone lists 209 species. Some beetles protect your tomatoes, some bore into your shade trees, and a few do both jobs in different life stages.
This guide profiles 12 beetles that Maryland residents are likely to meet in yards, gardens, woodlots, and fields. Each profile covers how to recognize the beetle, where it lives, and whether it helps or harms. For a wider view of the group, the worldwide count of beetle types shows how small this 12-beetle sample really is.
| Beetle | Appearance | Typical Habitat | Role |
|---|---|---|---|
| Flatheaded Appletree Borer | Flattened, bronze-gray, metallic | Orchards, yards, woodlots | Tree pest |
| Tiger Beetle | Metallic green, long legs | Sunny trails, sandy banks | Predator |
| Margined Leatherwing | Orange-yellow with dark markings | Flowers, meadows | Predator, pollinator |
| Goldenrod Soldier Beetle | Yellow-orange with black marks | Goldenrod patches | Predator, pollinator |
| Locust Borer | Black with yellow zigzag bands | Black locust trees, goldenrod | Tree pest |
| Red-headed Ash Borer | Slim, brown, yellow bands | Firewood, dying hardwoods | Wood borer |
| Red Milkweed Beetle | Red-orange with black dots | Milkweed patches | Milkweed feeder |
| Striped Cucumber Beetle | Yellow with three black stripes | Vegetable gardens | Crop pest |
| Spotted Cucumber Beetle | Yellow-green with black spots | Gardens, fields | Crop pest |
| Seven-spotted Lady Beetle | Red with seven black spots | Gardens, fields | Aphid predator |
| Spotted Lady Beetle | Pink to red, elongated | Corn, gardens | Predator |
| Green June Beetle | Metallic green with copper edges | Lawns, fruit trees | Fruit and turf pest |
1. Flatheaded Appletree Borer
The flatheaded appletree borer (Chrysobothris femorata) is a metallic wood-boring beetle that sneaks up on stressed trees. Adults are about half an inch long, flattened, and bronze-gray with a coppery sheen. They show up in late spring and summer, often basking on sunny trunks.
The damage comes from the larvae. These pale grubs have a broad, flattened front end, which gives the group its “flatheaded” name. They tunnel beneath the bark of apple, maple, oak, and many other hardwoods, and they prefer newly planted or drought-weakened trees.
Pro Tip: Young trees that scorch in Maryland’s summer heat attract borers first. Water new plantings deeply during dry spells and shade the trunk with a tree wrap through the first seasons.
Healthy, established trees usually fend off attacks. Gardeners who want a broader picture of what shares their yard can browse the different types of insects that live alongside beetles.
2. Tiger Beetle
Tiger beetles are the sprinters of the insect world. The six-spotted tiger beetle (Cicindela sexguttata) is a shimmering green beetle that darts along sunny woodland paths and lifts off just ahead of your boots. The University of Maryland Extension names the six-spotted tiger beetle among the important predatory ground-dwelling beetles in the state.
Adults hunt ants, flies, and other small prey with large jaws and sharp eyesight. Their larvae wait in vertical burrows in bare soil and snatch passing insects. Look for them in spring and early summer on dry, exposed ground.
BeetleIdentifications.com also lists the Puritan tiger beetle (Cicindela puritana) for Maryland. This rare relative clings to eroding Chesapeake Bay cliffs, so it is a species to admire from a distance. Readers across the Potomac can compare notes with the types of beetles in Virginia, where several of the same predators patrol trails.
3. Margined Leatherwing
The margined leatherwing (Chauliognathus marginatus) is a soldier beetle with soft, flexible wing covers, which explains the “leatherwing” nickname. Its orange-yellow body carries dark markings, and the wing covers are edged in a lighter band. The Maryland listing at InsectIdentification.org includes the margined leatherwing beetle.
Adults gather on blooms to eat pollen and nectar, and they also pick off aphids and other soft-bodied insects. Their larvae hunt in leaf litter and soil. University of Maryland Extension counts soldier beetles, or leatherwings, among Maryland’s important predatory beetles.
Margined leatherwings are harmless to people and pets. If you see a cluster feeding on garden flowers, leave them alone, because they are doing pest control for free. You can read more about listed species in the InsectIdentification.org Maryland index.
4. Goldenrod Soldier Beetle
The goldenrod soldier beetle (Chauliognathus pensylvanicus) is the showiest of Maryland’s leatherwings. BeetleIdentifications.com lists it as the state’s representative soldier beetle. Adults are yellow-orange with black patches on the wing covers and thorax, and they reach about half an inch.
Late summer and fall bring them out in numbers. Goldenrod and aster meadows from the Eastern Shore to Garrett County can hold dozens on a single flower head. They eat pollen and nectar and also catch small insects, and they sometimes mate right on the blooms.
Their sheer numbers can look alarming, but they do not bite crops or sting. Neighboring states have similar flower-loving beetles, as the types of beetles in Ohio guide shows.
5. Locust Borer
The locust borer (Megacyllene robiniae) is a longhorn beetle dressed like a wasp. Its black body is crossed by bright yellow zigzag bands, and its long antennae sweep back along the body. BeetleIdentification.org’s Maryland list includes the locust borer beetle.
Adults feed on goldenrod pollen from late summer into early fall, so you can often find them on the same flowers that draw soldier beetles. After mating, females lay eggs in bark crevices of black locust. The larvae then tunnel through the wood, weakening trees and leaving them prone to wind breakage.
Black locust grows across much of the eastern United States, so similar sightings turn up in the insects of New York, too. Thinning stressed locusts and keeping them well watered is the usual advice for reducing borer attacks.
6. Red-Headed Ash Borer
The red-headed ash borer (Neoclytus acuminatus) is a slender longhorn beetle with a reddish head and thin yellow bands across brown wing covers. Adults run quickly over wood in a jerky, wasp-like way. They are usually under three-quarters of an inch long.
Despite the name, this beetle attacks many hardwoods, not just ash. It favors dying trees, fresh-cut logs, and stored firewood. Homeowners most often notice it when adults emerge from a woodpile, which looks alarming but rarely signals harm to a sound house frame.
Important Note: Anyone who suspects a beetle is an Asian longhorned beetle should capture it and report it to the Maryland Department of Agriculture immediately. That invasive species is sometimes mistaken for sawyer beetles of similar size and pattern.
Native borers like this one are part of the forest recycling crew. Invasive species are the real concern, so when in doubt, take a clear photo and ask your local extension office.
7. Red Milkweed Beetle
The red milkweed beetle (Tetraopes tetrophthalmus) is hard to miss on a milkweed leaf. Its bright red-orange body is dotted with black, and each eye is split in two by the antenna base, which gives it the nickname “four-eyed” beetle. Adults reach roughly half an inch.
This beetle eats milkweed and nothing else as an adult. Its warning colors advertise the bitter toxins it absorbs from the plant, so birds usually leave it alone. When grabbed, it makes a faint squeaking sound.
Gardeners who plant milkweed for monarch butterflies in Maryland often find these beetles moving in. They chew leaves and sometimes feed on flowers, but healthy plants typically shrug off the damage. Compare regional milkweed visitors with the types of beetles in Minnesota, where the same beetle follows milkweed across the northern states.
8. Striped Cucumber Beetle
The striped cucumber beetle (Acalymma vittatum) is a small yellow beetle, about one-fifth of an inch long, with three bold black stripes down its back. It emerges in spring and heads straight for cucumbers, squash, melons, and pumpkins.
Adults chew leaves, flowers, and young fruit. They also spread bacterial wilt, which can collapse a healthy vine within days. That disease is usually a bigger threat to Maryland vegetable growers than the chewing itself.
Pro Tip: Cover seedlings with lightweight row cover until flowers open, then remove it so bees can pollinate. Early protection blocks the beetles during the most vulnerable stage.
Scout in the morning, when beetles are sluggish and easy to knock into a bucket of soapy water. Replacing infected vines quickly also limits spread.
9. Spotted Cucumber Beetle
The spotted cucumber beetle (Diabrotica undecimpunctata) looks like the striped version after a paint change. It is yellow-green with 12 black spots and a black head, and it measures about a quarter inch.
This beetle is less picky than its striped cousin. Adults eat leaves and blossoms of beans, corn, squash, peas, and many ornamentals. The larvae, called southern corn rootworms, feed on roots of corn and peanuts in the soil.
That wide diet makes it a persistent garden pest from the Delmarva Peninsula to the Piedmont. Rotating crops and keeping weeds down around beds reduces the places adults can shelter. Since the striped and spotted species often show up together, check both when you scout your cucurbits.
10. Seven-Spotted Lady Beetle
The seven-spotted lady beetle (Coccinella septempunctata) is the classic ladybug: bright red wing covers with seven black spots, a black head with pale patches, and a rounded dome shape. It is native to Europe and now thrives across the United States. The Maryland State Archives names this species as its example of a beneficial beetle.
Ladybugs eat soft-bodied pests, and the numbers are impressive. According to University of Maryland Extension, one ladybug can eat over 5,000 aphids in its lifetime. Adults and larvae both hunt, so tolerate the odd-looking alligator-shaped larvae on your roses.
Spring is the best time to attract them. Plant dill, yarrow, and fennel for pollen, and skip broad-spectrum sprays that kill beneficial insects along with pests. Beetle diversity in the mid-Atlantic is also reflected in the types of beetles in Tennessee, where lady beetles are equally common.
11. Spotted Lady Beetle
The spotted lady beetle (Coleomegilla maculata), also called the pink spotted lady beetle, is a native species with an elongated oval shape. Its wing covers range from pink to red-orange, with black spots and a black stripe down the middle where the covers meet. Adults are about a quarter inch long.
It is common in corn fields and vegetable gardens. Beyond aphids, it eats mite and insect eggs and also feeds on pollen, which helps it survive when prey is scarce. That flexible diet makes it a dependable garden ally.
Mixing up lady beetles is easy, and the look-alike matters. According to PestCzar’s Maryland guide, the Asian lady beetle ranges from orange to red, has a dark M mark behind its head, and invades homes from fall through winter. Spotted lady beetles stay outdoors, which is one reason you will rarely find them inside the house. You can check the details in this occasional invader chart.
12. Green June Beetle
The green June beetle (Cotinis nitida) is one of the largest and flashiest beetles in a Maryland yard. It is about three-quarters of an inch long, velvety metallic green on top, with copper-tan edges and a bright metallic underside. Adults fly in the heat of summer with a loud, buzzy drone.
Adults gorge on ripe peaches, figs, grapes, and berries. Their larvae live in turf and eat decaying organic matter along with grass roots. They also have a peculiar habit of crawling on their backs across lawn surfaces after heavy rain.
Southern states see more of this beetle, so the types of beetles in Georgia give a useful comparison for how its range extends northward. Maryland’s warm, humid summers suit it well, especially on the Eastern Shore and in southern counties. Shaking beetles from fruit into soapy water is the simplest way to protect a backyard harvest.
All 12 beetles here show how much variety fits into one state. Many are allies, a few are pests, and almost all are worth a closer look. If your backyard wildlife interest extends beyond insects, the types of snakes in Maryland make a natural next read.