When the evenings start to warm up, I like to grab a glass of tea and sit on the back porch and listen to the crickets. Then something changes. It typically starts later in June and peaks in July, although some hold on until frost. The incessant nighttime calls let me know that summer has truly arrived. Sometimes it even seems like they are talking to each other, even singing together in a chorus, or maybe talking to me. Early settlers were scared by the mysterious noise made by something in the trees they could not see. They didn’t realize the noise was just coming from a small green insect called katydid. Katydids are in the Family Tettigoniidae and are related to grasshoppers and crickets, but katydids have antennae longer than their body’s. The long antennae are useful for navigating trees at night. Although there are at least 12 species of katydids in the Carolinas, the one that sings nightly and sounds somewhat like “katydid” is the true katydid (Pterophylla camelliafolia). The true katydid’s genus name, Pterophylla, means wing leaf because the insects look like a leaf. Even the veins of the leaves resemble the veins of leaves. Great camouflage for an animal that spends most of its life amongst the leaves. Apparently, someone thought they looked like a camellia leaf, thus the specific epithet camelliafolia. Other members of the family Tettigoniidae include common coneheads and meadow katydids, but they do not have the impressive, some people may call it obnoxious, nighttime call.
Although both sexes can sing, it is usually the male that is heard on summer nights as they try to impress the females. They don’t really sing, they stridulate. Stridulation is similar to a violin but produces a raspy staccato noise that sounds somewhat like “katydid.” They rub the rough edges of their forewings together to make noise. The wings bend outward slightly creating a chamber that increases the volume of the sound, somewhat like an echo chamber. Although they have wings, they are poor flyers and usually walk or hop. When there are large numbers of males in an area, they can synchronize their songs together to further increase volume. The females choose their mate based on the quality of the male song which is detected with hearing organs on their front legs. The song is more rapid on warm evenings and slows when temperatures drop. Depending on where you live, the song can be slightly different with the northern dialect more clearly saying “katy did.”
Katydids are rarely seen and are most active at night. During the day, they rest motionless, so they appear to be a leaf. When katydids aren’t resting or singing, they may be feeding on leaves, but they rarely cause major damage to the plant. Mammals, birds, and lizards consume katydid, but the great golden digger wasp captures and paralyzes katydids and grasshoppers. It then buries the paralyzed victim and lays an egg on it. When the egg hatches, it feeds on the still living katydid.
True katydids are about 2 inches long with the females larger than males. They are green, but sometimes katydids are born pink. These pink katydids are easy to find and quickly eaten by predators. Females have an ovipositor at their rear for laying eggs in the soil or on plant stems or bark. When laid on a stem, the flattened eggs are laid in rows. In the spring, the eggs hatch into nymphs. Nymphs look like tiny versions of adults. The nymphs will go through several molts as they grow. At later nymph stages, they will form wings and an ovipositor if female. The ovipositor is sickle shaped in the true katydid but can be longer and saber-shaped in other katydid species. When they mate, the male provides a sperm package called a spermatophore. Attached to the spermatophore is protein the female can eat to increase egg development. I guess it is kind of like a dinner date. Males that offer large food gifts may mate several times. Males with smaller food gifts are less likely to mate. A larger food gift is an indicator of better male health and genetics.
More information on katydids can be found here:
https://songsofinsects.com/katydids/common-true-katydid
https://hort.extension.wisc.edu/articles/katydids/
https://hgic.clemson.edu/great-golden-sand-digger-wasp/
https://kanecountyconnects.com/article/katydids-insects-kanecounty-environment
Cranshaw, W., and D. Shetlar. 2017. Garden insects of North America: The Ultimate Guide to Backyard Bugs (2nd ed.). Princeton University Press.
Author
Robert Carter, Cooperative Extension, Area Forestry and Wildlife Agent
Clemson University Cooperative Extension Service offers its programs to people of all ages, regardless of race, color, religion, national origin, disability, political beliefs, sex, marital or family status and is an equal opportunity employer.
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