Cattail Toothpick Grasshopper - Leptysma marginicollis

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Moved from Cattail Toothpick Grasshopper.

… David J. Ferguson, 7 May, 2009 - 11:06am

Compare Stenacris, Achurum? (I'm confused!)

Wow, are these things confusing. There are three rather superficially similar "toothpick" grasshoppers:
1-Stenacris vitreipennis--Glassywinged toothpick grasshopper
2-Leptysma marginicollis--Cattail Toothpick Grasshopper
3-Achurum carinatum--Longheaded toothpick grasshopper

Refer to page 8 of Grasshoppers of Florida, Stenacris vitreipennis--Glassywinged toothpick grasshopper. That reference states:

"Similar Species. Stenacris vitreipennis is easily confused with Leptysma marginicollis (Serville), but in L. marginicollis the head is as long as, or longer than, the pronotum whereas in S. vitreipennis the head is shorter than the pronotum. The antennal segments, although flattened, are not nearly as wide as in L. marginicollis."

Hmm. I can't quite tell on your photo--the pronotum thing. Then, what about Achurum carinatum--Longheaded toothpick grasshopper? See page 2 of this PDF. All three are looking alike to me--I need to look at the print version of that book--the illustrations are clearer. I'd really like to see these things--am envious of your Florida escapades.

Thanks, as always, for the great photos. I'm just trying to figure these out for myself. Can you tell me how you reached the id. here?

Patrick Coin
Durham, North Carolina

… Cotinis, 20 October, 2004 - 7:11pm

These are tough but...

Hey Pat,

I know, these grasshopper keys are tough. I had to look a bunch of words up to make sure I was doing this correctly.

Longheaded Toothpick Grasshopper - I know this wasn't A. carinatum. For one, this was a much bigger, and thicker bodied, grasshopper (and it still wasn't full grown!) So I marked that one off the list of possibilities.

The Pronotum - Now, the pronotum is the dorsal (top) plate on the thorax. In this photo you can see that the head is just as long as the pronotum, in fact, it may be a tad longer. So one point for L. marginicollis.

Antennea - If you compare the antennae segments in the little jpegs on the "Grasshoppers of Florida" pdf, you can see the difference in the width between the 2 species.

Surfing around the internet, I found one image of S. vitreipennis at Gallery of Florida Insects, again you can see the thinner antennea. University of Guelph has an image of an adult L. marginicollis which illustrates the wider antennea segments and which looks closer to this image. So I deduced that this was a nymph of Leptysma marginicollis...

Again, I am an amateur. I work with what I can find to make these determinations, but I am always open to be corrected or taught by more learned bugpeople (like Eric:)

Hope this helped...

… Tony DiTerlizzi, 6 December, 2004 - 9:33pm

another comment

Thought I'd throw in another comment relating to Achurum. A few quick and easy traits that are usually visible in photos. The "knee" of the hind femur in Achurum has very distinctive points that stick backward (not so in the other two genera). The eyes of Achurum aren't striped prominently. Achurum has a concave face. This photo isn't Achurum, but if you go to that genus, you can see these things quite clearly. Achurum also lacks the prominent spur on the "throat" between the front legs that the other two have (but you have to pose the insect to photograph this). There are other similar looking "toothpick" genera, but they aren't a consideration in the southeast. Your ID as Leptysma is correct and well done.

… David J. Ferguson, 1 January, 2008 - 6:45pm