Facts
- Katydids are most common in the Amazon, but can also be found in your local park!
- Katydids are nocturnal
- Size: 1 to 5 inches long
- Food: mostly leaves.
- Natural predators include wasps, ants, mantis’ and frogs.
- Katydids can fly but not very well.
You must have seen these insects many times when they come to lights at night (particularly genera Amblycorypha, Scudderia, and Microcentrum). In Europe flying members of this subfamily are poorly represented and katydids in general are rare visitors of porch lights and windows lit at night.
Diet
What Do They Eat?
Most katydids can be categorized as opportunistic omnivores. This means that although many of them specialize on certain kinds of food, such as insects or leaves, they will nevertheless accept other food if the opportunity arises. For example, the great majority of species of the subfamily Phaneropterinae, a group you are most likely to encounter if you live in North America, feed on leaves and flowers of a variety of plants. Still, many will eat other plant material, such as fruits or vegetables, and some are known to attack and eat insects, including members of their own species.
Finding & Keeping Them
If you would like to keep phaneropterine katydids alive for some time, put them individually in large jars with plenty of room for the insect to move around, covered with a lid with holes, or sturdy plastic or metal mesh (many katydids will chew right through cloth mesh). You can feed them a variety of fruits and vegetables, such as lettuce, carrots, apples, or cucumbers, just make sure that these weren’t sprayed with pesticides. Many katydids will also gladly accept flowers of all kinds. Change their food at least every other day and never let it rot or mold in the container. Spray the container with water to prevent the insects and their food from drying out.
Other katydids that you may run across quite frequently in North America are members of the cone-head subfamilies, especially the genus Neoconocephalus. Most of them are grass and seed feeders. In captivity you can feed them with carrot and sunflower seeds, as well as fresh blades of grass (try to give them the same species of grass on which you found the insects).
Occasionally you may find other species of katydids, such as shield-backed katydids (genus Atlanticus and its relatives in N. America, Decticus and close genera in Europe). Feed them a mixture of fruits and vegetables as well as freshly killed dead insects.
Don’t expect your katydids to live long in captivity. Most adult katydids do not live more than 2-3 months, often less.
Differences Katydid vs Grasshopper vs Cricket
How do I know if I have a katydid, a grasshopper or a cricket?
Telling these three groups apart is relatively easy. Katydids (or bush-crickets) have long, threadlike antennae, usually longer than the body. Males have the basal part of the front wings modified for sound production (often this area is of a different color than the rest of the wings) and females usually have a distinct, sickle- or sword-shaped ovipositor at the end of the abdomen. Most katydids are green and have long wings.
Crickets
Crickets are usually brown or black, and like katydids have long, thin antennae. Males of crickets also produce sound by rubbing their wings against each other, but unlike katydids the area of the wing modified for sound production covers almost its entire surface (there are exceptions in both groups). Female’s ovipositor is thin, needle-like. Most crickets are stout and more compact than katydids.
Grasshoppers
Grasshoppers have short, relatively thick antennae, which are rarely longer than half of the body. Males produce sound by rubbing their hind legs against the wings sand have no visible modifications on the surface of the wings (most North American species don’t produce sound at all). Female’s ovipositor is short, often barely visible. Most common grasshoppers are brown or olive-green.
Please remember that these descriptions are extremely simplified and that there are many members of the three groups that can be easily confused with others.