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Handsome Tachinid from AZ gathering - Vanderwulpia sequens

Handsome Tachinid from AZ gathering - Vanderwulpia sequens
Montosa Canyon Road, Santa Cruz County, Arizona, USA
July 26, 2013
I found this tachnid a ways down the dry wash not far from where the BugGuide group saw the tiger rattlesnake. I only got two shots before it flew off, and yesterday I started to work on IDing it from this, the nicer image.

Searching BugGuide it looked like tribe Minthonini was a good match. There are only two nearctic genera in that tribe: Paradidyma and Vanderwulpia. And this promising image from the NADS Tachinid Resources web site looked good, as did the thumbnail image of Vanderwulpia sequens below:

Then I checked out my other photo, taken 40 seconds before the one at the top of the page:

I had thought they were the same individual in the field, but I now realized otherwise. The pollinose stripes on their scuta were quite different; the r5 (="1st posterior" or "apical") cell is closed at the wing margin here, but open on the other; and the eyes here appear closer (a male?) than on the other (a female?). And on the other, the eyes are pilose...which rules out genus Vanderwulpia according to couplet 287 of the Tachinidae key on pg. 1260 of the MND(1). Rechecking this image, I couldn't tell for sure whether the eyes were truly bare (with those short white hairs at the lateral edge perhaps sticking out from the back of the head) or if the eyes were pilose but not well enough in focus to clearly discern except at the edge.

If the eyes are truly bare, I think this would be Vanderwulpia sequens, as there are only two species listed on the NADS Tachinidae catalog, and the other, V. atrophopodoides has 1st posterior cell petiolate and a conspicuous red on the abdomen, see below:

But if the eyes here are pilose (as they definitely are on the companion post), then I think this will turn out to be Paradidyma. The NADS Tachinidae catalog lists 6 Arizona species of Paradidyma, and each of these species have descriptions written by H. J. Reinhard as follows:

        apicalis on pg. 33 of the Proc. US Nat. Mus. Vol. 83, No.2973 (1934);
        aristalis on pg. 28 of the Proc. US Nat. Mus. Vol. 83, No.2973 (1934);
        crassiseta on pg. 27 of the Proc. US Nat. Mus. Vol. 83, No.2973 (1934);
        melania (as synonym Metachaeta cinerosa) on pg. 268 of Entomological News Vol. 34 (1923);
        neomexicana on pg. 23 of the Proc. US Nat. Mus. Vol. 83, No.2973 (1934); and
        setigera on pg. 22 of the Proc. US Nat. Mus. Vol. 83, No.2973 (1934).

The first couplet of Reinhard's 1934 key to males of Paradidyma indicates that they either have apical (=1st posterior) cell closed and petiolate or open at wing margin. Since my specimen here has apical cell closed at margin but not petiolate, I'm thinking this may indeed be Vanderwulpia sequens if this is a male.

Otherwise, using Reinhard's 1934 key to female of Paradidyma seems to lead to P. setigera.

As always, any corrections or confirmation are welcome and appreciated.

Moved from Tachinidae.

Tachinidae: Vanderwulpia sequens
Tachinidae: Vanderwulpia sequens

Thanks, Norm
...for the ID/confirmation. That seemed to me where this was headed :-)

If you have an idea of male vs. female here, that would be nice to know (and I'd update the appropriate check box for the post).

Compare fore legs
If my ID of this fly as the same species is correct

your fly has smaller pulvilli on the fore legs. That is often a sexually dimorphic character (larger in males).