Fishy, fishy

Fish bones are quite common at Carmel Church. On any excavation we will turn up dozens to hundreds of individual bones, but these are mostly unidentifiable scraps. There are certain elements we get quite frequently (dentaries, premaxillae, and vertebrae, for example). What we almost never get are multiple associated elements from a single fish. That’s why I was so excited back in April, 2010 when Tim and I found an apparent set of associated fish vertebrae (above). Over the last week I’ve finally had a chance to prepare these vertebrae:

As I suspected in the field, this is the tail from a large fish, but it’s more complete than I originally realized. We have the last 10 vertebrae, including the fan-shaped hypural at the posterior end. The preservation is remarkable. We even recovered most of the overlapping spines that lock the vertebrae together, best seen in ventral view:

The large size, rectangular-section posterior vertebrae, plate-like interlocking spines, and lateral keel (visible on the fourth through sixth vertebrae from the left, below) all indicate that this is a scombrid, the family that includes the mackerels and tuna, and in fact it seems to be a good match for the genus Thunnus (tuna). We have identified several Thunnus specimens from Carmel Church, including hypurals and the rectangular caudal vertebrae, but this is by far the best example we have.

This is also an impressive specimen because of its size. The preserved section is about 37 cm long. Using proportions of modern tuna as a guide, that gives a total body length on the order 220 cm. Yet it’s probably not the biggest fish we have from the quarry.

Incidentally, after finding these vertebrae in April, 2010, on our very next excavation Tim found a major part of a large fish skull less than two feet away. I mentioned at the time that the proximity of these specimens was at the very least intriguing. It was even more interesting when we found a large articular (part of the lower jaw) mixed in with the vertebrae:

In typical Carmel Church fashion, the site was just messing with us. The skull and the vertebrae are from different fish, since the skull is almost definitely not a scombrid. The skull appears to be a sciaenid, most likely a red drum fish. I’m not sure about the articular. I’m pretty sure it’s not a tuna, but I’m not convinced that it’s a drum fish either; it might represent a third large fish.

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

2 Responses to Fishy, fishy

  1. George says:

    Burch

    have had alot of work with Calvert Bony fish years ago an idurated piece of zone 10 pelld off and I took it back and donated it to the SI Bob Purday indiicated it was a scombroid

    All the best

  2. Boesse says:

    The more anterior vertebrae definitely look like Thunnus – I published a vertebra identified as Thunnus sp. from California in one of my papers last year, and it’s a dead ringer for what you’ve got here (albeit smaller). That’s a spectacular find! I think 99% of the Neogene bony fish record outside laminated flat-slab occurrences are completely disassociated bones.

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