Identifying Praying Mantis: 4 US Species and Egg Cases

To identify a praying mantis in North America, check four things: its length, how far the wings reach down the abdomen, the spot between or on the inside of the front legs, and, if you find one, the egg case. Colour is not one of them; Natural Lands notes that all four common species range from brown to green.

• Length. The Chinese mantis is the largest in North America at just over 11 cm (Wikipedia), about 5 inches (Piedmont Master Gardeners). The European mantis is 6 to 8 cm for females. The native Carolina mantis is about 2 inches, with females 47 to 60 mm (Wikipedia).
• Wings. In the Chinese mantis the wings run the full length of the abdomen (Piedmont Master Gardeners). In a mature Carolina female they stop short: Piedmont Master Gardeners says about two-thirds of the way down, Wikipedia three-quarters.
• Front legs. Look at the inside of the front legs where they join the body. The European mantis has a black eyespot with a yellow or white centre there; the Chinese mantis has a yellow spot between the front legs (Wikipedia).
• Egg case. A round, puffy, foam-like case about the size of a ping-pong ball is Chinese; a slender, smooth, striped one is Carolina (Piedmont Master Gardeners; Natural Lands). See the egg case section below.

• Chinese mantis (Tenodera sinensis): the biggest, just over 11 cm; brown or green, with a green stripe along the edge of the front wings in brown individuals and a yellow spot between the front legs (Wikipedia). Accidentally introduced in 1896 by a nursery worker at Mt. Airy, Philadelphia, it has spread throughout the Northeast but is absent from much of the coastal Deep South, Florida and much of the western United States (Wikipedia). Invasive.
• European mantis (Mantis religiosa): females 6 to 8 cm, males 5 to 7 cm; usually greener than the Chinese mantis (Piedmont Master Gardeners); the black eyespot at the base of each front leg is the giveaway (Wikipedia). Introduced to North America; Natural Lands says it was brought in decades ago for pest control. It is Connecticut's state insect (Wikipedia).
• Carolina mantis (Stagmomantis carolina): the native species of the eastern United States; females 47 to 60 mm, dusty brown, grey or green, short wings in mature females, and a dark dot on each forewing in both sexes (Wikipedia).
• Narrow-winged mantis (Tenodera angustipennis): an invasive Asian species first noted in Maryland in 1921, brown to green, best told by its elongated egg case, which often shows red streaks as it ages (Natural Lands).

Of the four common species in the eastern United States, only the Carolina mantis is native. A mantis that is 3 inches or longer, with wings covering the whole abdomen, is almost certainly one of the introduced species; one about 2 inches long whose wings stop well short of the tip of the abdomen, with a dark dot on each wing, fits the native Carolina mantis.

The difference matters to gardeners. Piedmont Master Gardeners reports that the larger invasive species outcompete the Carolina mantis for food and will eat it.

Mantises lay eggs in late summer and early fall inside a foam case that hardens; the adults die with freezing winter temperatures and the nymphs hatch in spring at around 70 °F (Piedmont Master Gardeners). The case is often easier to identify than the insect:

• Chinese mantis: round to cube-shaped, puffy, straw-brown and foam-textured, a little smaller than a ping-pong ball (Piedmont Master Gardeners; Natural Lands), roughly 2 cm across and holding up to 300 eggs (Wikipedia).
• European mantis: elongated and uniformly pale brown, with no striping (Piedmont Master Gardeners; Natural Lands).
• Carolina mantis: elongated, slender and relatively smooth, with lighter and darker stripes and a lighter central strip (Piedmont Master Gardeners; Natural Lands).
• Narrow-winged mantis: elongated, often with red streaks that show more after a few months (Natural Lands).

Natural Lands, a Pennsylvania conservation group, advises that people who want to limit the invasive species should not simply move Chinese mantis egg cases to a nearby field, since that only moves the problem; its suggestions include freezing the case for a week.

In everyday use, no. "Mantis" is the name for the whole group, more than 2,400 species in 33 families, and "praying mantis" comes from the prayer-like posture of the folded front legs (Wikipedia). The European mantis, Mantis religiosa, is the species most often given the name in its strict sense, but in North America people use "praying mantis" for any of them.

Both, which is why identification matters. Mantises are generalist ambush predators. Piedmont Master Gardeners reports that the Chinese and European mantises eat plant-feeding pests but also honey bees, bumble bees, flower flies and butterflies including monarchs, that more than 75% of their prey items in one study were herbivores, predators and pollinators, and that one researcher documented 147 cases of mantids catching birds, mostly hummingbirds. Natural Lands calls the Chinese mantis an indiscriminate predator that also takes native mantises, reptiles and amphibians. A native Carolina mantis in the garden is a different case from a large invasive one.

Finding a praying mantis is not rare in much of the eastern United States; the Chinese mantis alone has spread throughout the Northeast (Wikipedia). Because nymphs hatch in spring and adults die with the freezing temperatures of winter (Piedmont Master Gardeners), the full-size mantises people notice turn up mostly in late summer and fall.

Mantises are eaten by frogs, lizards and birds and by spiders, large hornets and ants, and some hunting wasps paralyse them to feed their young (Wikipedia). Larger mantises also eat smaller ones, including the native Carolina mantis (Piedmont Master Gardeners).

The sources used for this page do not show that mantises recognise individual people. What they do describe is unusually good vision for an insect: stereo vision, compound eyes with up to 10,000 facets, and in some species a head that can turn nearly 180° (Wikipedia). That is why a mantis appears to watch you and follow your hand.

Take a side view that shows where the wings end relative to the tip of the abdomen, and a view of the underside or inside of the front legs to catch the eyespot or yellow spot. Put a coin or ruler next to it, since length separates the Carolina mantis from the introduced species. Natural Lands recommends iNaturalist for community confirmation; InsectLens names the species from the photo.

Research and drafting for this page used AI assistance. Every figure, date and quotation was then checked line by line against the sources listed at the bottom of the page, each of which was opened while writing. Nothing here is a diagnosis. If a bite, sting or contact with an insect is followed by trouble breathing, swelling of the face or throat, spreading redness, fever or any symptom that worries you, get medical care; in the United States Poison Help (1-800-222-1222) is free and open 24 hours a day.