Rearing Conocephalus gracillimus

Disclaimer: The title of this post is a bit misleading, as my entire experience with this species consists of a single individual which I brought through its imaginal molt only. However, the story is an interesting one, and hopefully what I have learned here may be of use to others trying to rear meadow katydids.

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A last instar male nymph of Conocephalus gracillimus, the Graceful meadow katydid.

This February, I received a shipment of insects from around Fort Lauderdale, FL. In the past I have had no problems with shipments of live insects, but unfortunately, the weather in Ithaca at that time happened to be particularly nasty (-20 degrees F), so the majority of the critters perished en route. Of the 5 animals that survived, only one made it past the first week in captivity. That animal was a small brown meadow katydid nymph, who was missing his right hind leg. For some reason, he seemed unable to jump, despite still having one functional hind leg, and walked everywhere. Given that many of the other creatures that had died were much hardier species (roaches, beetles, spiders), I didn’t have much hope for this guy’s survival. I established him in a container, the setup of which is detailed below:

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The container is an empty couscous container with the lid removed and replaced with a fine mesh, which is held in place by a rubber band.

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Inside the container, there is a substrate of EcoEarth, the Floridian twigs he was shipped with, and two food dishes. One contains small pieces of carrot, the other contains fish flakes for protein. The inhabitant is visible on the far right.

This setup seemed to work for the first couple of weeks. His copious frass indicated that he was feeding well on the carrot slices and fish flakes. I misted the container with water once or twice a day, and replaced the food every couple of days. At this point I was still unsure as to his identity. I knew his tribe (Conocephalini) and given that he appeared to be a last instar nymph with large wing buds, I figured that he had to be in the genus Conocephalus (the only other genera in that tribe would either be much larger or have very reduced wings). Looking through the range maps and descriptions at SINA, I hazarded a guess that he could be C. gracillimus, a Florida endemic species which seemed to match up with the general habitus and color scheme. However, given that he was a nymph, it was too early to be sure. I would have to examine several traits which required him to be an adult male. I hadn’t had much hope for him earlier, but given his success so far, I now began to hope for him to become an adult.

About 3 weeks later, he stopped eating, as evidenced by the fact that no more frass was accumulating on the sides of the container. His wing buds also started to bulge, and his body color started changing slightly. These were all signs that he was due for a molt. I had learned that a humid environment is important for molting, so I replaced the mesh on top of the container with the original lid to reduce water loss. This might have stimulated mold growth, so I removed the uneaten food to avoid that issue. Then I waited. I figured that he would molt at night, as most katydids do, so I checked on him every morning. Nothing happened for a week, and then one day there he was in all his glory as an adult male, with long, elegant wings!

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Conocephalus gracillimus is not a large animal. Here he is perched on the tip of my finger.

Now that he was an adult, I placed the mesh back on top of the container so that I would be able to hear him once he started singing (meadow katydid calls tend to be extremely high-pitched and soft). I photographed him as he was, but since he was still teneral, I did not want to risk damaging him to get a look at his cerci. Judging from his overall appearance, my theory that he was C. gracillimus seemed more and more strong. Interestingly, he was now able to jump, although he could apparently only manage a weak little hop. 2.5 weeks later, his color had changed from the original brownish/pinkish hue to a more green/yellow shade, and his jumping abilities had improved dramatically. I decided to photograph him again, and this time I was able to image his cerci. Running him through the key in a paper by Rehn and Hebard (1915), and comparing images on SINA, I was able to conclusively pin him down as gracillimus, just as I had suspected from the beginning. Concidentally, the very next day he sang for the first time, and his song matched the recording on SINA perfectly.

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Adult male Conocephalus gracillimus, as he appeared while still teneral and then 2.5 weeks later, with his distinctively shaped cerci.

As of today (June 21th, about 4.5 months later!), he is still alive and well. He is very active and calls daily, although it’s very easy to miss due to his extremely quiet song. I wish I had a female so that I could try to breed them, but I don’t think I will be getting down to Florida any time soon. Regardless, I know now that Conocephalus gracillimus make good pets and are quite hardy in captivity should I ever run across this species again.

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Face of Conocephalus gracillimus

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