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Photo#167597
Platycerus oregonensis - male

Platycerus oregonensis - Male
Santa Clara County, California, USA
December 21, 2007
Size: 9mm
Okay, I've been looking at the really big one and thought it was something different. I didn't even bother looking at this specimen, I was taking it as P. oregonensis for granted. I believe I made a mistake. I believe this is actually Platycerus cribripennis. This is based on Benesh 1946.

Most important:
Denticulate inner margins of mandibles. I've looked over my specimen and those in the guide, and there is nothing even close to the denticulation shown on these mandibles. This separates it from the orgeonensis group.

Two other species are found in California, P. marginalis and P. cribripennis. Based on the heavy punctation of the head and the coastal range, I think this is the later. P. marginalis seems to be restricted to the Sierras. This species is primarily from the Monterey County regions, but I can't see why Santa Clara county would be much of a stretch, it's only about 60 miles north of Monterey. I'd appreciate your comments

Images of this individual: tag all
Platycerus oregonensis - male Platycerus oregonensis - male Platycerus oregonensis - male Platycerus oregonensis - male

This is Platycerus oregonensis
This image is of a fairly typical specimen of Platycerus oregonensis.

Platycerus cribripennis Van Dyke is a valid species. Give me a month or two and I'll have a paper out on it with Michael Caterino, who brought his specimens to my attention. P. cribripennis is only from Monterey and Santa Barbara counties in California, is covered in ocellate punctures, and looks nothing like the beetle shown here. The male even has a nice EXTERNAL tooth on the mandibles. Benesh never looked at the original specimen of P. cribripennis and had no idea what he was talking about, hence everyone's confusion on his 'synonymy'. Van Dyke had a much better grasp on the western Lucanidae.

Cheers.

 
I concede
I concede defeat. Thanks a lot Dr. Paulsen!

I must say that between the two specimens I pretty much nailed the size range!

 
Its not a defeat!
You have successfully come to understand the range of variation within this species! Congratulations! ;-)

 
Thank you!
Thank you!

Benesh
I've looked at the paper again. It seems that Platycerus cribripennis is considered there to be a "mutant", not even a subspecies of P. marginalis. That being said, I think it's safe to go with this as P. marginalis.

Definitely P. cribripennis. I
Definitely P. cribripennis. I have a pair of platycerus marginalis and it looks completely different. If I can get picasa to work I'll upload better picture of the P. marginalis pair.

 
synonyms?
Smith's list has them as synonyms - I'm certain there is solid basis for it, but not aware of the latest review.

 
Well....
Okay:

California Beetle Project list P. cribripennis and P. marginalis as separate

Nomina Nearctica lists them as separate (but it's usually wrong)

ZipCode Zoo also lists them as separate species.

Besides that, there seems to be a significant geographical isolation between the two groups, which combined with morphological differences lends credence to having them considered separate species.

 
fwiw
I know nothing about this species, but Evans & Hogue's "Field Guide to Beetles of CA" says there are 2 Platycerus species in CA -- P. oregonensis, and it doesn't say what the other one is ... which, combined with the list Phil links to above, implies they are going with marginalis.

ZipCode Zoo lists names that it finds on any and all other web sites and doesn't have any taxonomic authority. In this case it appears their Platycerus names came from GBIF's cache of specimen data, which is a great resource but which one cannot assume is up to date (nor, unfortunately, can one assume that all museums where their data came from have updated their Platycerus records lately!)

 
another source ICAGAS
Matt's page lists 4 species as well and he would know. I'll have to see if I can dig up what paper did this.

 
Change
I'll change this to P. marginalis, it seems pretty clear that P. cribripennis isn't legitimate at this point. I'm just delighted that I took a look at this thing, it had never occurred to me that it might be something other than P. oregonensis

 
I have a P. marginalis specim
I have a P. marginalis specimen and it looks completely different, does p. marginalis have a huge color variation?

 
The shape of the pronotum loo
The shape of the pronotum looks wrong for marginalis and marginalis has more obvious striae on the elytra without the blue highlights (at least in my experience).

 
P. oregonensis
P. oregonensis doesn't have denticulate inner mandibles though

 
Ya, but P.oregonensis is the
Ya, but P.oregonensis is the only one that has metallic blue wings. Dennis and I both posted a photo of platycerus marginalis and none have the blue. I think it might be just a minor male p. Oregonensis. I'll look at the UC Davis collection for comparison.

 
American Beetles
American Beetles lists 5 species in the US, with 4 found in the West Coast. The fifth lives in the Eastern US, so they obviously mean P. virescens. American Beetles actually lists the "Checklist of the Scarabaeoidea of the Nearctic Realm" by Smith, though they cite the 2001 list, so presumably there wasn't a conflict at the time. I don't know whether they changed it recently or not

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