Skip to main content

Making more music-makers

A Davis's tree cricket, Oecanthus exclamationis, in between fiddles. This little fellow is a contributor to the great musical backdrop of late summer and fall, courtesy of the Orthopteran symphony. Most tree crickets produce long droning trills, and as there are generally many of them in close proximity, tree crickets are major contributors to the sounds of the night.

The males are singing to attract mates, just as songbirds do. Tree crickets and other Orthopterans have their "ears" or hearing organs located just below the "knee" on the foreleg. This odd placement allows the ears to be about as far apart as possible, and that allows the animal to more accurately triangulate on sounds. And in the case of females, to better locate singing studs such as the guy above.

Ah! His melodious charms have worked! He's successfully wooed a mate, and she has joined him on the leaf. That's the female on top, which may seem to be an odd position. They are engaged in courtship feeding, a bizarre quirk of tree cricket reproduction. The male has an organ called a melanotal gland on his back, just behind the wings. This structure produces a tasty nutrient-rich substance that lures the female into an optimal position, and she is feeding from the melanotal gland in this photo. Once she's settled in, he'll curve his abdomen upwards to contact her genitalia and transform his spermatophores to her. Sometime after she's been successfully fertilized, she'll use her ovipositor to puncture bark on twigs and inject her eggs. Come the following spring, the eggs will hatch and a new crop of tree crickets will begin life.

While on a nocturnal field trip a week or so ago, Cheryl Harner spotted this scene and alerted the rest of us. It's a pair of short-winged meadow katydids, Conocephalus brevipennis, caught in the act of mating. The female is on the right, kindly holding her swordlike ovipositor aloft so as to not impale her mate. The male has managed to contort himself into a rather spectacular position; he must have studied the insect Kama Sutra.

The white globule is the spermatophore - we've caught him just as he was transferring his reproductive material to his mate. At the tip of his abdomen, just to the right of the spermatophore, we can see the specialized claspers that he uses to grasp and hold the female. These are called cerci, and each species of meadow katydid has uniquely shaped cerci.

The scenes in these photos are the fruition of the male's songs - successful courtship with a female, and perpetuation of the species. These Orthopteran romances play out by the score each night, all around us, but we seldom get to see them in action.

Comments

Popular posts from this blog

The Pinching Beetle, a rather brutish looking bug

The world is awash in beetles, and they come in all shapes and sizes. Few of them can match the intimidation factor of a Pinching Beetle, Lucanus capreolus, though. Those formidable looking mandibles look like they could slice off a finger.

Today was one of those coolly diverse days. I started off down in Fayette County, visiting the farm of a friend. He has restored about 25 acres of wetlands, and the response by the animal community has been nothing short of phenomenal. Blizzards of dragonflies of many species, amphibians galore, and nesting Blue-winged Teal, Pied-billed Grebe, and Sora. Among MANY other things. And all in a short two years. Add water and they will come.

Then, working my way home, I ducked into a Madison County cemetery that has a thriving population of Thirteen-lined Ground Squirrels, and shot images of our native prairie dog. Then, I stopped at a spot along Little Darby Creek, waded on in, and procured some pretty nice shots of various stream bluets and dancers. …

Calliope Hummingbird in central Ohio!

A hatch-year male Calliope Hummingbird strikes a pose. Small but tough, the hummingbird was feeding actively yesterday in 39 F temperatures. It frequents feeders and gardens at a home in Delaware County, Ohio, about a half-hour north of Columbus.

Fortunately, the wayward hummer appeared at the home of Tania and Corey Perry. Tania is a birder, and knew right away that the hummingbird was something special. For a while, the identification was up in the air, which isn't surprising. The Calliope Hummingbird used to be placed in its own genus, Stellula, but has recently been submerged into the genus Selasphorus, which includes Allen's, Broad-tailed, and Rufous hummingbirds. The latter two, especially, are quite similar to the Calliope in subadult plumage. Rufous is the default "vagrant" hummingbird here, with dozens of records and birds turning up annually. There is but one Ohio record of Allen's Hummingbird, from late fall/early winter 2009. Ditto the Calliope Hummi…

Ballooning spiders

Fear not, ye arachnophobes. The subject of this entry is indeed about spiders, but the star of the show is about as cute as a spider can get. And you'll want to know what we're about to learn...

On my recent West Virginia foray, we were strolling down a seldom-used lane, when a bright yellow object caught our eye. It was a goldenrod crab spider, Misumena vatia, on top of a post! Not only that, she - it is a girl - was acting extraordinarily goofy. The spider would stilt up as high as she could go on her legs, weave back and forth, jig side to side, and otherwise engage in what appeared to be spider break-dancing.

Click the pic for expansion, and you can see two columns of silk issuing from her spinnerets. This is an important point, as we set about determining what this non-web-making spider is doing.


So fixated was our spider on her task that she even rejected what would seem to me to be a perfectly scrumptious meal. This little caterpillar climbed rapidly up the post and dire…