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Cannibalism-  - Phidippus princeps

Cannibalism- - Phidippus princeps
Concord, Middlesex County, Massachusetts, USA
August 1, 2009
I'm fairly certain these are both immature P. clarus. Its possible they are siblings and probable they are closely related. A draining experience to say the least.

Images from video at::
Natural History Services - Jumping Spiders

Images of this individual: tag all
Cannibalism-  - Phidippus princeps Cannibalism-  - Phidippus princeps Cannibalism-  - Phidippus princeps

Moved from Phidippus clarus.

Not a clarus
I think both might be P. princeps; maybe 5th or 6th instar. You should post the abdomen view from about 8s into your video. Actually, if you haven't bugged G.B. much lately, you might ask him to take a look, since I'm not sure how distinctive princeps is at this stage.

Took me a minute to figure out exactly what's going on here. In the second image the spider appears to be eating a molt (note the clear eyes), which would be very odd, but in this image the abdomen is still fully formed. The additional views in the video make it quite clear that the "two-headed" prey had just started the molting process when the predator discovered it as an easy meal. So I guess what we are witnessing is the removal of "poor molting site selection" from the gene pool.

Or maybe, just maybe, we're looking at two newly discovered species, which I shall call Phidippus heracles and Phidippus orthrus. :-)

P. othrus Hmmmmm . . . .
As you once so sage-like said, salticids will inevitable lead to alcohol! I am guilty of identification by association. While mature P. clarus are in the immediate vicinity (the same milkweed patch!), I have not (knowingly) seen P. princeps in the area where the video was shot. Both species ARE in the general area and so these may well be just what you say. I have posted an image of the abdomen and hope this helps. As to your suggested names for the "new" species I claim priority and suggest P. barnesii obfuscatum. And now for a cold beer . . .

Good call Jay . . .
G. B. Edwards was kind enough to comment - "Phidippus princeps is a distinct possibility. They have a dorsal pattern (but not color) similar to P. audax when immature, losing the pattern in about the subadult stage. I would have to see the venter of the abdomen to be sure (P. clarus is very distinctive), but Jay could be right."

And to add a footnote of my own - today I revisited the milkweed patch where the video was shot and there, perched on a milkweed pod, was a sub-adult P. princeps. I think this is a great example of how much BugGuide and its talented experts and editors have to offer. Thanks Jay!

Just glad I wasn't horribly wrong :-)
I'll go ahead and move to P. princeps then, since his only comparison was to P. audax.

The venter would indeed help to confirm this as P. clarus, but the dorsum spot pattern should already rule out that possibility.