Katydids: A Short, Sedentary, Solitary Life
Discovered Quite by Accident
We recently discovered two female Katydids in our yard and our curiosity was aroused, as both of these had what appeared (to us) to be egg sacks hanging from the backside. We were wrong of course, and my research resulted in this article, which will show you some photos and explain exactly what it was that we were seeing. At this point, I would like to refer you to the section entitled “Breeding.”
The body of a Katydid resembles a green leaf, right down to the detailed veins, and we spotted these quite by accident. Apparently, we didn’t scare or threaten them, as they are known to fly away quickly in those cases.
All of the photos were taken by Michael McKenney are of the two female Katydids on our backyard plants, although there are hundreds of species found all around the world. We're pretty sure there's a male Katydid in our yard somewhere, although we haven't seen him yet.
Katydids usually fly only when they are disturbed or threatened, so their wings function more like parachutes, breaking their fall as they leap from one place to another.
Katydids are related to crickets and grasshoppers (in the order Orthoptera) and are usually green sometimes with brown markings. They are medium-sized to large insects and have a thick body, which is usually higher than it is wide. Their legs are long and thin and the hind legs are longer than the front or middle legs and are usually used for jumping. Their chewing mouthparts are on their head along with two long, thin antennae that extend back at least to the abdomen.
Adults of some Katydid species are able to fly, and virtually all of the species are camouflaged to blend in with their surroundings (mainly leaves). In all species of Katydids, their front wings have specially-shaped structures that are rubbed together in order to create sounds. They are equipped with flat patches on their legs that serve the same purpose as a human’s ears (called a tympanum, a slit-like or flat patch on each front leg), which enable them to hear the sounds of the other Katydids. They are able to pick up the sound more clearly by raising their leg.
Males Sing in Unison
There are several things about Katydids that are noteworthy, none of which is more interesting than their mating calls, one of the loudest and most familiar calls of summer. Katydids are nocturnal “singers” and each different species has its own characteristic song. The males apparently sing in unison, but they are not trying to harmonize...far from it. They sing by rubbing one of their hind legs against one of their wings, and each of the males is trying to sing out the loudest and be the first to hit a note in order to attract a female mate.
Scientists have discovered that the females of several acoustic insects such as Katydids, when given the choice of two identical males, have been shown to be partial to the one that leads in the mating call.
The songs of Katydids differ as to their purpose. The singing might be for mating purposes, as described above, or for establishing a territory. The song could also be a sign of aggression toward other insects, or for establishing a defense against threats.
Songs are species-specific, but different species are able to hear the calls of others.
There are hundreds of Katydid species and they are found all over the world except on the southernmost continent of Antarctica, a virtually uninhabited ice-covered landmass. On the other hand, as is the case with most insect groups, the greatest numbers of their species are found in the tropical, frost-free areas of the world. They are not social insects and don’t live in groups. As a matter of fact, rarely will you ever see more than one of them in any small given area. They are considered to be solitary and sedentary creatures, having no interaction with humans at all.
Although Katydids are not endangered, some species have become rare because of the disappearance of some particular habitats or food plants they need.
There are over 250 species in North America, most of which are in the family Tettigoniidae and divided among 7-10 sub-families. The ones that are more commonly found are the “true Katydids” (Pseudophyllinae), the “false Katydids” (Phaneropterinae), “meadow katydids” (Conocephalinae), “shield-backed Katydids” (Tettigoniinae, often divided into three subfamilies), and “cone-headed katydids” (Copiphorinae, often included with the meadow katydids.
What we had originally thought to be an egg sack dangling from the back of the Katydid turned out to be a packet of sperm cells that are passed from a male to a female. The female in the photo above is starting to stretch her head below and backward to the jelly-like substance, the outer layer of which she will eat.
The female, in order to lay her eggs, will use an organ at the back of her abdomen called an ovipositor. With precision, she will inject her grey, oval-shaped eggs onto a stem, leaf edge or on the ground. The eggs are laid at the end of summer or beginning of fall and are dormant during the winter months, hatching in the spring.
The Growth Cycle of a Katydid
Katydids have incomplete metamorphosis. The nymph that hatches from an egg of a Katydid looks a lot like an adult but missing the wings. As they grow, they shed their exoskeletons in a process called molting. During their final molt, they gain their wings and become adults, which is the end of their growing and molting.
The life of a Katydid is usually a short one – most live for only about a year or less. Usually, only the eggs of a Katydid are able to survive the winter although, in tropical areas, some adult species are able to live for several years.
Predators of Katydids
Their ability to camouflage has aided the Katydids, but they are not without some natural predators during their brief lives, including snakes, birds, some spiders, frogs, bats, and shrews. They have learned to adapt and have come up with ways to hide, having been born with an uncanny ability to pose like leaves and mimic other insects.
The Diet of a Katydid
Katydids in areas other than the tropics are primarily leaf-eaters, although they often eat other plant parts and are also fond of flowers. They have been known to eat dead insects, insect eggs and aphids, especially in the tropics where they are mainly predaceous (preying on other animals).
How the Katydid Got Its Common Name
Katydids get their name from the perceived sound they make with their repetitive calls and clicks, and over the years there have been people who believe that the call of a Katydid sounds like someone calling out the words "Katy Did! Katy Didn't! Katy Did! Katy Didn't!" so that’s where the common name comes from. Both the male and female are capable of making the sound.
- Hartbauer, M. & L. Haitsziner, M. Kainz, H. Romer (2014), Competition and Cooperation in a Synchronous Bushcricket Chorus, Royal Society Open Science Journal, Royal Society Publishing, October 8, 2014
- Forey, Pamela; and Cecilia Fitzsimons (1987), An Instant Guide to Insects, Gramercy Books, New York
© 2018 Mike and Dorothy McKenney