Blister beetles are an interesting bunch of beetles. There are about 300 species in the US primarily found in the Southwest, and they vary in color from brown, black, to gray, and may have yellow, reddish orange, black, or white stripes or spots. They’re about an inch to an inch and a half in length, have elongated, pliable bodies, long legs, compound eyes, a bowed head, and a distinctivethread-like antenna.
The master blister beetle, or Lytta magister, is a mix of deep black and bright red orange in color. You may find these beetles by the swarm in Phoenix during springtime, dangling from flowering brittlebushes.
When threatened, these beetles pop a blood vessel on their leg joints which secretes a bad smelling, yellowish substance that contains cantharidin, a burn agent (or a poison in large doses) that is colorless and odorless. When in contact with human skin, it causes painful blisters, hence why the beetle is called a blister beetle. It’s this same secretion that deters birds and mice to feed on these beetles, and leaves them to propagate their species in peace.
A male beetle courts a female by climbing on her back and sweeping his antennae across her head. If the male beetle is smaller than the female beetle, she refuses. When they do mate, they can stay attached to each other for hours, with some couples being observed to be attached for more than 24 hours. During this time, the female beetle goes about her business feeding from flower to flower with the male attached to her back.
Once they finish mating and separate, the female flies off to find a place where she can lay her eggs in the ground and she then promptly leaves them to their fate. Once these eggs hatch and turn into beetle grubs, they then burrow into the soil in search of food, which come in the form of grasshopper eggs. Sounds harsh for the little grasshopper babies, but bees may have it worse.
Other species of blister beetles have newborn larvae called triungulin. These triungulin pack themselves together by the hundreds to mimic the look of a female bee (they even smell like a female bee). When a male bee comes along to try to mate with fake bee, the triungulin then latch on to the male bee’s body and some of them get off when the male bee comes into contact with other actual female bees. Eventually these triungulin find their way to the bee’s nest where they feast on bee larva and their food. Other choice snacks include eggs of wasps and locusts.
If you find an infestation of these beetles on your property, call a professional exterminator to take care of them for you so you can remain blister free!
The order of Coleoptera is the most diverse group of insects – not only that, but there are actually more species of beetles than any other kind of animal in the world. That’s 25% of all known types of animal life-forms, and about 40% of all insect species.Pretty impressive, right?
In the state of Arizona, you can find around 90 different kinds of beetles, but we’ll just be talking about some of the more common ones you can find in your backyard – what they are, what they look like, and where you’ll find them.
Palo Verde Borer Beetles
These beetles are active during the summer, and are commonly seen flying around during sunset looking for a mate (you know, because it’s just more romantic during sunsets). They’re called Palo Verde Borers because as larvae, they develop underground near the roots of Palo Verde trees. They consume these roots and spend about 3-4 years as grubs, before maturing to adult beetles that only live about a month (after they mate and lay eggs, that’s pretty much it for them). They are dark brown, have long and straight antennae, large mandibles, spines on their thorax, and are commonly mistaken for large cockroaches.
Ladybird beetles, also known as ladybugs, are perhaps the most popular beetles in the world thanks to cartoons and children’s toys. They have hemispherical bodies, and while they come in a number of different colors, the most common color combination of these bugs in the US are red or orange with black spots. They are commonly found in gardens from spring to fall, and feed on aphids and similar insects. As larvae, they are purple with orange spots.
Cactus Longhorn Beetles
As the name would suggest, these beetles feed on cholla and prickly pear cacti. As larvae, they develop inside the cacti, and as adults, feed externally on soft cacti. They don’t fly, and are easily recognizable by their hard black bodies that have a white stripe behind the head. They also have long antennae that have a white spot at midpoint, which makes for a very interesting look. They’re usually active during daylight in spring and summer.
These beetles are so named because they eat fruit and sap. They like sweet food, which for them also includes leaves and flowers. Adult fig beetles have a dull green color and have shiny green undersides, with a tan stripe along the edges of their wings. As larvae, they feed on decaying plant matter, and interestingly enough, move by crawling on their backs. These beetles are active from late spring through summer, and are commonly found around trees.
If you’ve lived in Arizona long enough, then chances are you’ve seen a Palo Verde beetle or two – or more, since they come out by the hundreds of thousands between July and August. The Palo Verde root borer beetle, so-called because as grubs they especially enjoy munching on distressed roots of the Palo Verde tree, look like burlier cousins of the cockroach and can grow to around 3 to 3.5 inches long, making it one of the largest beetles in North America.
They range from dark brown to black in color, have wings that are almost as long as their bodies, and long antennae. They also have spikes on their thorax or middle section, and these may be sharp enough to cut through skin if you pick them up.
Though they prefer Mexican Palo Verde trees, they’re also found on olive and rose trees. While similar species are found throughout the northwest, these beetles in particular are most common in the Phoenix and Tucson areas.
Every summer monsoon season, like clockwork, these beetles take to the air to find love. They can spend about a month looking for it, before they die. If they find it before then, they’ll crawl back underground near tree roots to lay their eggs before expiring. Their larvae, creamy white in color and growing up to 5 inches, then spends about3 to 4 years munching on distressed tree roots before emerging from their homes to begin the cycle all over again.
While these flying insects may look terrifying, they’re completely harmless. Once mature, they feed on fruit and nectar and while they are pretty harmless to other insects and animals, coyotes, bobcats, owls and others may find them to be a tasty treat. During their larval stage, those that may snack on them include coati, skunk, and even bears.
They are most active during the early evenings and are attracted to lights, so during their mating season, you may find them on your porch looking forlornly for other Palo Verde beetles to mate with.
There’s really not much you can do to ward off these beetles, besides investing in netting or screens for your porch or patio. Other than that, make sure the trees on your property and even immediate area are healthy with proper water and fertilizing, since their larvae don’t enjoy fresh, healthy roots and the beetles may end up looking elsewhere to lay their eggs.
If you’d like to enjoy a night out during these months when they’re most active, you may want to head to an indoor restaurant or bar instead. If riding a bicycle or a motorcycle during their mating season, make sure to always wear your proper safety gear and expect to encounter a Palo Verde beetle or two during your rides so you aren’t taken by surprise (and possibly get into an accident). If you like driving with the windows open or the top down during the evenings, consider avoiding these until after their mating season when they go back underground.