Not only are katydids masters of disguise, they also have a multi-colored life cycle, and they hear with their lower legs! There’s just one good-sized (3 centimeter) green katydid in Oregon and it’s a fun one: the fork-tailed bush katydid (Scudderia furcata).
I found the tiny katydid above at Mount Pisgah in May of this year. The early instars (stages before adult) sport some orange and red markings. Young Scudderia furcata also have a unique black pointed horn on their head and impressively long, black-and-white-striped antennae. The little ones can’t fly, so they use psychology tricks on their predators: Their spines and colors imply that they can’t possibly be good to eat. They go through six stages of growth, shedding skin each time, and become more green as they add wings and reproductive organs.
Adult wings develop the shape and even the vein structure of green leaves. I found the adult pictured above a week ago in the north part of the park. This is a male fork-tailed katydid. In the profile shot, you can see the yellowish cerci under the “forked tail” reproductive organ that gives the insect its common name. Females have curved, scythe-shaped ovipositors that they use to lay eggs between the tissue layers of leaves!
The third picture above highlights the pitted area below the katydid’s front “knee” which serves as a hearing organ. Male katydids rub their wings together to call out to females, and both sexes have these leg-based “ears.” Our Pacific Northwest species doesn’t sound like it’s saying “katy-did,” but rather, calls in short bursts that sound like the flicking of a lighter, or like scissors snipping hair. If I had to spell it, it’d be something like “tzit.” There’s a link below with a couple of recordings. After playing the recordings, listen to your yard or a park in the evening. You’ll probably realize you’ve been hearing them all the time without knowing it.
P.S. In the southern U.S., some Scudderia furcata are pink!
Stay curious!
Sources:
Songs of Insects site: http://songsofinsects.com/biology-of-insect-song. Also has a page for this species: http://songsofinsects.com/katydids/fork-tailed-bush-katydid. Accessed 8/20/21
Article about Scudder’s katydids with a photo of one laying eggs: https://thesmallermajority.com/2013/08/18/they-can-count-too/. Accessed 8/20/21.
Eric Eaton’s page: http://bugeric.blogspot.com/2014/02/fork-tailed-bush-katydid.html. Accessed 8/20/21.
