Dusky-faced Meadow Katydid? - Orchelimum nigripes

Orchelimum nigripes

Accroding to Thomas Walker, this is definitely a female Orchelimum nigripes. He is interested in posting your photo on SINA. Here is his site, and contact info is on there as well. http://buzz.ifas.ufl.edu/

… Lynette Elliott, 14 March, 2005 - 10:49am

O. nigripes

Thanks for the info, Lynette.

… Robin McLeod, 17 March, 2005 - 3:30pm

O. nigripes

I have a copy of Part 14 of the "Insects and Arachnids of Canada" which deals with Grasshoppers etc. from Agriculture Canada. Just looking through that I would tend to go with O. nigripes. One of main distinguishing features is the tibae is blackish. They look blackish in picture but it might be the shadow and perhaps they are brownish? Other feature is the ovipositor. Nigripes has one shaped most like this. The only other species shown that shows this strongly curved ovipositor is O. campestre.

One thing in camestre's favour is it is shown with a range north to Toronto while nigripes is shown only just reaching into ontario in Essex County. So you may be right after all. Hmmm ... Is that tibae blackish?

… David Bree, 12 March, 2005 - 9:13pm

another possibility?

I've added a close-up shot showing spines on the hind femur, which, according to the key mentioned previously, would rule out O. campestre. However, the tibiae look brown in sunlight, which would rule out O. nigripes. That leaves only O. silvaticum which apparently has femoral spines and green to brown tibiae. The range of O. silvaticum shows 2 disjunct records from Long Island and the tip of Georgian Bay in Ontario, so an out-of-range record wouldn't be the first. But you mentioned that the only other species having a strongly curved ovipositor is O. campestre. Now what?

… Robin McLeod, 13 March, 2005 - 8:58am

hind femur

My reference says "Lateroventral margin of hind femur with 3 or 4 spines" is diagnostic for silvaticum. I think those spines shown in your picture meet that criteria (so hard when you don't have other specimens to compare). As for the ovipositor, Part 14 doesn't actually show silvaticum, but it suggests it is like O. vulgare which is shown as somewhat curved though not as extensively as I think this photo shows. Still if those are lateroventral spines I have to think you are right and this is silvaticum.

Nice photos but so hard to know without experience what part of the beast one should be showing to figure out species.

… David Bree, 13 March, 2005 - 10:24am

O. nigripes

Thanks for all the info, David. Lynette reports (above) that Thomas Walker calls this individual O. nigripes, which was your original choice. If O. nigripes can have brown hind tibiae (in good light, it's obvious that my specimen's hind tibiae are not black) then the key I mentioned earlier becomes unworkable because the other species in that couplet (O. silvaticum) can also have brown hind tibiae. Hmmm. If one aspect of a key is questionable, I wonder what other aspect(s) might be open to question.

… Robin McLeod, 17 March, 2005 - 4:36pm

cricket keys

As a matter of interest I have heard from those in the Entomology field that the keys in the Agriculture Canada monograph I am using are quite difficult to use. One of the reasons is the reliance on leg colour - blackish, brownish - all a bit vague. The grasshopper ones are even more difficult apparently. On the plus side there are all kinds of diagrams.

Another way to do this if you are situated right, is to visit a friendly university insect collection and see what they might have. I've done this with variable success depending on the group, keys available and insects in the collection. Also there is always some difference between a living creature and an old dried specimen, particularly in leg colour!

… David Bree, 17 March, 2005 - 5:29pm