by Carl Strang
Identifying species of small meadow katydids (genus Conocephalus), especially nymphs, can be challenging. Most adults are readily sorted out, especially males if you can get a good look at the cerci or claspers at the tips of their abdomens. Females are trickier, but their ovipositors often allow distinctions to be made. I’ve decided to take a shotgun approach in my survey at Mayslake Forest Preserve, sweep sampling on a weekly basis and taking photos of as many individuals as I can. Last week I noticed something that is potentially helpful.
As I compared my many photos, I found that the color pattern on the sides of the hind femurs drew my eye. Notice the band of clear green color bounded by brown stripes on either side. Here’s a female, again clearly a short-winged.
Again the color pattern on the femur appears. I did an Internet search, and except for some photos from Texas, short-winged meadow katydids show this striping pattern across eastern North America. Then I began to compare other species. I started with another familiar one, the slender meadow katydid.
Again an Internet and reference book search showed consistently clear green femurs on this species. However, I was surprised to find that a female I had identified a couple years ago as a slender meadow katydid had the femur stripes.
Next I turned to two species I have been seeking, which could overlap with the short-winged’s habitat. Straight-lanced meadow katydids in references and Internet photos lack the short-winged’s stripe pattern, instead often showing a diffuse blackish zone down that face of the femur. I went to photos of females I tentatively had identified as that species last year.
Others prove, on closer inspection, in fact to have been short-wingeds.
The other species I need to sort out is the prairie meadow katydid. Few photos of this one are out there. In some there is no stripe pattern like the short-winged’s, in some there is a hint of one. For now I will need to focus on cerci (straighter, more pointed and with distinctly longer teeth than the short-winged male’s) and ovipositors (proportionately more curved than the short-winged female’s). I am encouraged, however, to continue looking for details of color pattern that might provide short-cuts to field identification at least in regional or local populations.