Straight-lanced Meadow Katydid

by Carl Strang

The Kankakee Sands bioblitz gave me the opportunity to learn more about the straight-lanced meadow katydid. My only certain identification in northeast Illinois was a male in Kane County last year. I had photographed some females with long ovipositors, but most of these seemed better fits as short-winged meadow katydids. An open area at the Conrad Savanna State Nature Preserve proved to have an abundance of straight-lanced, and they were the only members of their genus (Conocephalus) in that location.

This was a dry sandy-soil spot with grasses, whorled milkweed, hoary vervain, and a Lespedeza species as the major plants.

Mature females left no doubt.

The ovipositor length consistently exceeded the insects’ body length. Some of the literature I had seen had given femur length as the measure, but my experience in northeast Illinois had given me doubts.

Late-instar female nymphs likewise had exaggerated ovipositors.

In this one the ovipositor is much longer than the body.

Though I could hear the incessant buzzing, free of ticks typical of meadow katydid songs, that supposedly marks the straight-lanced song (using the SongFinder, of course), searching and sweep sampling produced just a single male, a nymph in the penultimate instar.

Already the cerci are showing extended flattened tips that will be even longer at maturity. They are long enough here to be diagnostic, I think.

I was paying attention to femur color patterns as well. Note the diffuse blackish stripe on the male nymph. I think this will prove to be diagnostic, when present. It is lacking in the mature female in the first photo, however. From this experience I am inclined to regard body length rather than femur length as the measure the ovipositor needs to exceed on a mature female meadow katydid to be considered a straight-lanced. Going back through my photo records, I found only one that met this criterion.

This one I caught in the dolomite prairie at Waterfall Glen Forest Preserve in 2010. Note the blackish stripe on the femur.

This was one of the two highlights of my singing insect survey at the bioblitz. I’ll share the other in my next post.

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