|
|
Post by takahe on May 6, 2011 23:28:57 GMT -8
Presumably another Onthophagus, from Delta County Michigan. About 6 mm long.
Bradleigh
|
|
|
|
|
|
Post by thanos on May 7, 2011 7:37:24 GMT -8
I think that this is the female of O.hecate.
Thanos
|
|
|
|
Post by bandrow on May 7, 2011 8:58:00 GMT -8
Bradleigh,
Look closely at the pronotum - if it is hecate, it will be covered in granules - tiny little bumps - and not have punctures. It will also be covered in short, stiff hairs. All of the other species in the area will have a punctate pronotum...
Cheers!
Bandrow
|
|
|
|
Post by prillbug2 on May 7, 2011 15:59:59 GMT -8
My rough guess based upon the keys is Onthophagus orpheus pseudorpheus Howden and Cartwright, if the elytral intervals, especially 5, are distinctly punctate, anterior tubercles lacking or barely visible; pronotal punctures rather widely spaced, shallow, lacking anterior tubercles; dorsum, and in the females the frontal carina is highest near the eyes; setae of the pronotum and elytra conspicuous.
If not, then it's Onthophagus orpheus orpheus (Panzer), or O. orpheus canadensis (Fabricius), which are frequently found in Michigan.
That's my guess without all of the information available to me about the underside. Check the elytra and make a decision.
Jeff Prill
|
|
|
|
Post by thanos on May 7, 2011 22:57:19 GMT -8
He must examine these details under stereoscope to be sure, although the colour doesn't look to me to fit to O.orpheus. O.orpheus is more shiny,bronze and metallic greenish,in contrast with the more mat black O.hecate.
|
|
|
|
Post by bandrow on May 8, 2011 20:04:03 GMT -8
Greetings,
I agree, Thanos - all three subspecies of O. orpheus are very shiny and green or purplish. And judging by the size of the pin head (just a guess, mind you) that this specimen is too big to be orpheus as well.
Cheers!
Bandrow
|
|
|
|
|
|
Post by prillbug2 on May 9, 2011 19:30:34 GMT -8
The other option is Onthophagus striatulus since it is uniform brown to picous, or black with iridescent reflections. Also, the size fits at 4.3 to 7.2 mm. I've collected all of them and they can be quite variable.
What he needs to do is find a key and do it himself. Photographs don't give us all of the picture. I mean look at the resutls, we have three different possibilities for a Onthophagus that can easily be identified using a key. I find that very inefficient.
Jeff Prill
|
|
|
|
Post by bandrow on May 10, 2011 7:47:17 GMT -8
Bradleigh,
To help with images, try and get better lighting on the top of your bugs. If you are using the camera's flash only, try supplemental lighting from the side (both sides if possible) to illuminate the dorsal surface better. I know this is easier said than done unless you invest in expensive light units or a light box, but a little creativity might solve the problem. The camera flash often washes out colors which can be captured if there are multiple light sources. It's a matter of experimentation...
Good luck!
Bandrow
|
|
|
|
Post by takahe on May 11, 2011 22:39:56 GMT -8
Yes the lighting has been a problem. I've been experimenting a little and concluded early on that the flash is not the best way to go. Natural light has worked somewhat better. I agree it is a matter of experimentation. And I admit I don't have very advanced equipment.
I am going to try locating some keys. For the time being I was just trying to get some rudimentary ID's so I have a general idea where to place these specimens in my collection (in regards to phylogenetic order). I'm rearranging everything and eliminating the unit trays in drawers with lots of large specimens.
Bradleigh
|
|
