Carmel Church Day 8

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After awhile excavations often settle into a routine. You begin to get a sort of feel for the pit, and you start to focus on removing bones you’ve already found rather than finding new things. At Carmel Church it’s a bit more complex, because in trying to remove one bone we often find several new ones.

While making a trench around yesterday’s large whale vertebra, Laura found several new bones, including an incisor from the fish Tautoga (above). She also recovered a tiny vertebral epiphysis (the cap from the end of the vertebra), just 3 cm in diameter:

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An even more unusual bone came out of the same trench:

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I’m pretty sure this is the right supraorbital process of the frontal from a small odontocete such as Xiphiacetus (although it could be some other taxon). It’s pretty worn, but I think the rough surface is where the maxilla originally covered the frontal.

Meanwhile, the west side of the pit has also been producing a number of bones. Tim found a fairly large vertebral epiphysis a few days ago, which I removed this afternoon:

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Underneath the epiphysis was a large Isurus tooth:

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Late yesterday afternoon, Drew found an elongate bone on the west side of the pit, and this afternoon Mike was able to remove it:

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This is a fragment of an odontocete lower jaw, which are very rare at Carmel Church (I think this is the 4th). It’s from somewhere out toward the tip of the jaw where the two dentaries are fused along the mandibular symphysis, so parts of both dentaries are preserved. The teeth have fallen out, but the tiny tooth sockets are visible along each side. There are also additional fragments still in the ground which could possibly be part of this same jaw, but I’m not sure about them yet.

At first glance this jaw seems consistent with Xiphiacetus, in which the lower jaw is long and narrow. Now, I know what you’re thinking: what about the possible Xiphiacetus frontal you found today? Are they from the same whale? Well, the two bones were found more than 2 meters away from each other, so I think it’s unlikely. In fact, last March we actually found a partial fragment of another possible Xiphiacetus lower jaw between where these two bones were found.

Tomorrow I plan to work on the other fragments from the vicinity of the mandible.

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This entry was posted in Carmel Church Chondrichthyans, Carmel Church odontocetes, Carmel Church Osteichthyans, Carmel Church Quarry, Chesapeake Group. Bookmark the permalink.

2 Responses to Carmel Church Day 8

  1. Brian Beatty says:

    Hrm… That rostral fragment sure looks like Xiphiacetus, it isn’t likely to be any of the other odontocetes, other than other eurhinodelphinids. Alveoli are too small for anything else besides a platanistoid, but they tend to be spaced further apart.

  2. altondooley says:

    I agree, I think it’s Xiphiacetus too. But I think the frontal and the mandible are likely from different individuals of Xiphiacetus.

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