Scorpion - Anuroctonus sp? - Diplocentrus spitzeri

Moved

… Kari J McWest, 25 October, 2008 - 6:49pm

Diplocentrus spitzeri

Looks like an adult male Diplocentrus spitzeri (Family Diplocentridae).
Good Find! This is about as far north as it gets. So far, it is known from Patagonia to Nogales and a little bit into Sonora, Mexico. Little is known, really, of its true distribution.
Quite common around Rio Rico and Nogales, and to Pena Blanca Lake.

… Kari J McWest, 25 October, 2008 - 6:48pm

Thanks for the ID information . . .

Dear Kari:
Thank you so much for the identification help with this scorpion (Diplocentrus spitzeri). Just curious, what field marks make led you to this species? I still have much to learn about the order scorpiones!
Sincerely,
Scott Cox

… Scott Cox, 2 November, 2008 - 9:57am

Subaculear tubercle

You're most welcome, Scott! Glad I can help!

Scorpions in the family Diplocentridae have a very obvious feature which is barely visible in the photo: a thick subaculear tubercle. It also has large, powerful chelae (hands) that are reticulate (bumpy, ridged).

Diplocentrus spitzeri is the only species in that area. It is very similar to D. peloncillensis found a bit further east in the Peloncillo Mountains of the Arizona/New Mexico border.
If you did not provide locality info, one would have to count the spines on the bottom of the tarsi, the counts of which become a "formula" that helps ID species in the family, among other characters.

Anuroctonus is in the family Vaejovidae (not Iuridae) and does not occur in Arizona, or if so, only in the extreme NW part of the state. The telson of this genus is swollen at the beginning of the aculeus (stinger) in males only.

… Kari J McWest, 2 November, 2008 - 6:20pm

One more question . . .

Hi Kari:
Thanks again for your response and help. I hope you will entertain one more question from a novice. You wrote:
"Scorpions in the family Diplocentridae have a very obvious feature which is barely visible in the photo: a thick subaculear tubercle."
Can you help me understand "subaculear tuburcle" . . . perhaps pointing me to a diagram which illustrates this feature on scorpions?
Thanks again for you patience and help,
Scott

… Scott Cox, 5 November, 2008 - 12:18am

subaculear

Subaculear means below the aculeus, or stinger, so it is the big bump or tooth at the base of the sting.

Also, I goofed about the family for Anuroctonus! I meant to say family Iuridae, not Vaejovidae or Chactidae.

Check out the photos on this page:
http://johnbokma.com/mexit/2006/04/25/diplocentrus-species-scans.html

… Kari J McWest, 5 November, 2008 - 7:53pm

Excellent!

Thanks for the definition. I digitally enlarged my original photo and, although blurry, I could make out the subaculear tooth at the base of the sting. That is extremely helpful!
Thanks again,
Scott

… Scott Cox, 6 November, 2008 - 12:00am