Since I started at the park in 2001 my students and I have discovered and collected eleven complete and partial skulls, seven of them in the last two summers. Our most recent was discovered this last Tuesday and we were able to get it back to the lab by Wednesday afternoon.
The photo below shows the upper portion of the skull after being exposed. Half of the lower jaw is also present and slightly visible under the boulder to the left.
Below is a photo of the rear portion of the left side of the skull. The squamosal bone (the dark gray mass in the center of the photo) is narrow in dorsal (top) view and deep in lateral (side) view. Thus the skull is almost certainly that of a "Leptosuchus". Interestingly in 1921 Annie Alexander and Charles Camp of the University of California Museum of Paleontology collected the holotype skull of "Machaeroprosopus" ("Leptosuchus") lithodendrorum from a spot close by and at the same stratigraphic horizon.
The forward portion of the lower jaw was in a very hard sandstone matrix underneath a very large boulder at the site. In this third photo you can see the upper part of the skull already plastered and one of my interns is taking a turn under the boulder freeing the lower jaw. We were able to get it out and back to the preparation lab.
This hopefully will prove to be another nice skull for our collections.