Big scary Carmel Church fish

20131118-222754.jpgOn the first day of our Carmel Church excavation last November Christina found associated remains of a fish skull (above). This was pretty exciting, because associated fish remains (multiple bones from one individual) are relatively rare at Carmel Church. I did a little prep work in my hotel room (below), but the specimen was deeply weathered with a hard crust, as is typical of Carmel Church bones exposed at the surface. Further preparation had to wait until we returned to the museum.

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Finally, after about 60 hours of preparation time with a pneumatic pen, we’ve completed cleaning the specimen, and found quite a bit more than we expected. Even in the field we knew there were at least two tooth-bearing elements, which turned out to be the dentaries (the anterior part of lower jaws). Here’s the right side of the mandible in lateral view, complete with the angular and articular bones, shown next to the same bones from a modern specimen of a striped sea bass (Morone saxitilis):

2014-02-26a

And here’s the less-well-preserved left dentary (we didn’t recover the left angular or articular):

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The dentaries fit together nicely when viewed from above:

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It turned out that we had recovered several additional bones, including the right ceratohyal and hypohyals (in lateral view):

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These bones make up part of the hyoid apparatus, which supports the tongue and other soft tissues associated with the lower jaw. The hypohyals are the two small bones on the right, which are fused to each other in the fossil specimen; these bones would be in contact with their left counterparts on the midline (or nearly so). The large bone in the middle is the ceratohyal. The triangular bone on the right in the modern Morone specimen is called the epihyal, and we didn’t recover it in the fossil.

Here’s the left maxilla (part of the upper jaw):

2014-02-26d

I’m not certain about the identification of the next bone. I’m pretty sure it’s the right lacrimal, which extends from the lower front edge of the eye socket to the upper jaw. I’ve shown it beside the right lacrimal from Morone, but this bone seems to vary greatly in shape between different taxa:

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Finally, we also recovered a very poorly-preserved right premaxilla (so there were actually three tooth-bearing elements in the specimen):

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This premaxilla is interesting, because back in 2010 Christina found a very similar (and much better preserved) left premaxilla in the same general part of the quarry:

2010-06-26a

The 2010 premaxilla is very similar in size and shape to the new specimen:

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In fact, the 2010 left premaxilla even articulates perfectly with the left maxilla from the new specimen:

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I doubt the 2010 specimen is from the same individual, but I do think it’s likely from the same species.

So, what species is it? Clearly it’s not Morone, as all the examples above are quite different in their details. I’m not sure of the identification, but at the moment I’m leaning toward a snapper from the genus Lutjanus. In particular, compare the dentary and angular to Lutjanus images at OsteoBase, and the lacrimal to this Lutjanus image from BioLib. Unfortunately we don’t have a specimen of Lutjanus in the VMNH collection, so I’ll have to wait for confirmation. If these two specimens do turn out to be Lutjanus they will be the first examples of that taxon identified from Carmel Church.

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2 Responses to Big scary Carmel Church fish

  1. George F says:

    Butch

    My guess is Gadus sp. It may also be Scaienops which is found in the Eastover sediments. Gret prep work and what a great find.

  2. altondooley says:

    I’m pretty sure it’s not Gadus; the shape of the dentary is wrong and the teeth are too large, I think. Scaienops is common at Carmel Church, but the mandible in this fish is more robust than apparent Scaienops mandibles from Carmel Church, and the shape of the premaxilla and premaxillary tooth arrangement are different.

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