Scutelleridae - Pachycoris klugii

Pachycoris stallii

This could very well be Pachycoris stallii, the range of which is more in line with being found in Arizona. P. stallii is highly host specific to Croton Californicus, which is found in the southwest U.S. and northwest Mexico. I have not found any documents describing anatomical differences between Pachycoris species, so range and host plant (typically a Spurge of some sort) may be the best way.

Ref:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1615236/#i1536-2442-5-29-1-williams1

https://link.springer.com/article/10.1023/A:1005692502595

… DFee, 30 December, 2020 - 11:51pm

Croton californicus is found in the southwest US

But I don't think you'll find it in southern Arizona. Maybe the range of P. stallii is geographically closer to Arizona, but southern Arizona more closely resembles areas of P. klugii's range in terms of plant life.

If P. stallii is highly specific on Croton californicus, I think that pretty well eliminates it as an option here.

… Andrew Meeds, 31 December, 2020 - 9:50am

Moved tentatively

Moved from Pachycoris torridus.

… v belov, 5 December, 2009 - 2:53pm

Arlene--

the bug is indeed a remarkable find!
I inquired Dr. Eger about the status and range of Pachycoris north of Mexico, and he told me that P. torridus is a southern species that barely reaches into Mexico, where it is replaced by P. klugii, but neither reach the US. All the records of P. torridus from the US are apparently based on a single old and questionable record from California in Van Duzee's 1917 ‘Catalog of the Hemiptera of America North of Mexico’. Dr. Eger hasn't seen specimens from the US, so the presence of Pachycoris in Arizona is news to him. It is probably P. klugii.

… v belov, 5 December, 2009 - 2:52pm

Moved

Moved from Shield-backed Bugs.

… Lynette Elliott, 5 October, 2007 - 8:45am

Thanks...

...for your detective work, Lynette!

… Arlene Ripley, 5 October, 2007 - 10:30am

Thanks to Lynette, . . .

. . . we now know what it is.
This bug is identical with the third specimen in this reference about Pachycoris torridus, the single species listed as nearctic in ITIS and NEARCTICA.

… Boris Büche, 5 October, 2007 - 12:39am

In reading the article....

...it mentions the following:
"Pachycoris torridus Scopoli 1772 is the most studied in the
family Scutelleridae in Brazil (Silva et al., 1968), being more
commonly found in South America and quite rarely in Mexico
(Peredo, 2002). This species is very similar to the Mexican
species, P. kluggi, causing confusion......".

Since we're a lot closer to Mexico, and I can't find any web images of P. kluggi, I'm wondering if this bug may actually be klugii?

… Arlene Ripley, 5 October, 2007 - 11:53am

I read that too...

Let me do some more work on this and get back to you.

… Lynette Elliott, 5 October, 2007 - 12:27pm

Scutelleridae

closely related family. Very remercable species!

… Boris Büche, 4 October, 2007 - 2:27am

Thanks,

Scutelleridae it is. Guess that's about as specific as we can get with most members of this Family.

… Arlene Ripley, 4 October, 2007 - 6:16pm

Cool markings...

I googled for a while and found some similar markings in the Pachyseris genus of shield bugs. See google here. I don't know which species we have in N. America.

… Lynette Elliott, 4 October, 2007 - 8:57pm

Yes, ....

it does look very similar to the Pachyseris photos found in Google images. Too bad they were not taken in N.A.

… Arlene Ripley, 4 October, 2007 - 11:12pm