Above left: The dragon-headed katydid’s strong, sharp mandibles can crush and tear food like seeds and other insects. Above right: This female dragon’s “tail” is its ovipositor, used to lay eggs in plant material. Left: Keepers were unsure how to encourage these katydids to reproduce, but they discovered that the stem of a banana plant was just what one female katydid wanted, and she laid a neat row of elongated eggs inside it.
We placed the eggs in an incubator, and within several weeks, we had an abundance of adorable miniature “dragons.” It was an exciting development—not only is this a first for us, but, as far as we know, no other US organization has successfully hatched or raised this species.
On the Case
Growing Knowledge
Very little is known about the natural history of the dragon-headed katydid. Caring for and encouraging reproduction in this species required some detective work and experimentation on our part. A female katydid, like many insects, has a structure called an ovipositor that she uses to deposit eggs in an appropriate place for them to develop. While the closely related grasshopper uses its ovipositor to lay eggs in soil, different katydid species use their specialized ovipositors to lay eggs in a myriad of materials. The dragonheaded katydid’s ovipositor is shaped like the blade of a sword, and it is paper thin and exceedingly strong. This was a hint to us that they might lay their eggs in crevices—but of what?
Since we had never raised these insects from hatch before, and because of the dearth of information about them, we knew little about what their nutritional needs would be as they grew. Challenge accepted! We threw a little bit of everything into their diet and carefully monitored the hatchlings for clues. This katydid’s strong, sharp mandibles are the perfect tool for crushing and tearing things, but neither the adults nor hatchlings showed any interest in hunting. We supplied the hatchlings with various combinations of vegetables, fruits, grains, seeds, and even honey. We also offered them peanut butter, bee pollen, chitin powder, fish food, and popcorn. After trying so many food items, we found that what really made a difference was animal protein—they readily devoured dead crickets! In the wild, they would most likely be omnivorous scavengers, eating whatever fruits, seeds, and dead insects they came across. With the right food, our captive-raised katydids grew and thrived—and kept reproducing! We’ve been able to share some offspring with other institutions and currently have a healthy group of adults on display, all of which were raised here at the Zoo. We’re thrilled to have our own cadre of dragons and to be able to add to the collective knowledge about this enigmatic insect.
Hole in One We found some anecdotal evidence that in the wild, this species lays eggs in palm trees. Eager to follow any lead, we offered them pieces of split, rotten palm trunks as well as soft wood and soil—all to no avail. Next, we added a bananna plant to the enclosure, and soon noticed strangely shaped holes chewed into the side of the stem. Upon further investigation, we discovered eggs! A female had chewed a hole in the stem, slid her ovipositor between the layers of plant tissue, and laid a series of creamy-white, elongated eggs all in a row.
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