Zandmotor Finds (The Netherlands, North Sea Coast)

[acetabular]

I went to the Zandmotor recently while visiting The Netherlands and wanted some clarity on some of my finds. I found a number of shells, two fish vertebrae, and two different mammalian bone fragments. This, however, is all I can make of any of them, and would appreciate more specific ID's if anyone out there knows. The shells should be middle Pleistocene (if they're not actually recent shells lol), and everything else (likely) late Pleistocene. Thank you!

 

Fish Verts:

 

Perhaps not fossil-- Baltic Macoma? 

 

Not sure about this either (whelk?), lovely shell either way:

 

Mammal Chunk 1:

 

Mammal Chunk 2:

 

Mammal Chunk 1 again:

 

More Shells (Oysters, a gastropod, and a cockle (I think)): 

Edited October 22, 2021 by acetabular

[Tidgy's Dad]

Nice finds. 

@Max-fossils

[Ludwigia]

I agree with Macoma balthica, but I'm afraid that I can't help with the other things.

[acetabular]

Thank you!

[hemipristis]

 re top two verts:  the one on the right looks fishy. Cant tell about the left one without a side shot

Edited October 23, 2021 by hemipristis

[pachy-pleuro-whatnot-odon]

On 10/23/2021 at 9:30 AM, hemipristis said:

 re top two verts:  the one on the right looks fishy. Cant tell about the left one without a side shot

 

I agree, the two vertebrae look like fish vertebrae - which is the only place I've ever seen these kind of concentric circles descending into the concavity of the vertebral body.

 

As to the bits of mammal bone: I'm afraid these are too generic for identification (although #1 seems to likely be a bit of skull and #2 possibly a long bone), so would probably classify as Chunkothere.

 

I believe @sjaak has some experience with this kind of material, however, so may be he can chip in. Otherwise, I can really recommend you to ask your question again at the Paleontica-forum, where there are a lot more members versed in material from this location (the forum has a Dutch and English section, but I think best results would be obtained from posting in the Dutch section). Also, as someone who's searched the Zandmotor himself a couple of times now without much luck, I need to say this is definitely not a bad haul!

[Max-fossils]

Hi there, I'm a bit late to the party but as someone who's been to the Zandmotor countless times I think I may be able to chip in a little. 

 

The first two vertebrae are definitely from bony fish; they're very common there. However it's gonna be difficult to be anymore specific, so just keep them as "Teleostei indet." These are probably Eemian, late Pleistocene (120'000y).

 

Then for your "Macoma", those are definitely not Macoma balthica, but instead Spisula solida (although the small ones at the bottom could also be Spisula elliptica. One of the most important features to look out for when identifying bivalves is the hinge area, as it is often very distinctive. Luckily for us, Spisula and Macoma have quite an obvious hinge difference which makes them very easy to tell apart. Here are some examples from my collection (these specimens are from the Banjaard, another location in the Netherlands, but it's the same formation. The fossil shells from this location do have a somewhat different coloration to the ones from the Zandmotor but that's just due to the sediment in which they fossilized; so don't worry about that). Note how Spisula has that little "spoon" thing in its hinge area, and two lines going out of the hinge on the sides (these are called lateral teeth), features that are absent in Macoma. Also, the shell of Macoma is round on one side and tapered on the other, whereas Spisula is more symmetrical. Most of your shells unfortunately look modern to me: for the fossil shells (which are typically from the Eemian, late Pleistocene; 120'000y) on the Zandmotor, look for light-grey shells that are matte. If they seem glossy, have vivid colors, or let a lot of light through their shell, they're probably modern. 

 

That is a very nice whelk by the way! I'm pretty sure it's a Buccinum undatum. It looks modern to me, but I've rarely found fossil specimens of this species.

 

I can't help with the mammal bone chunks, and even very experienced paleontologists probably won't be able to either. Maybe if you can bring it into a museum where someone can look at it in person, that might help, but I still doubt it given how fragmentary the remains are. Probably best to just keep it as "Mammalia indet." They're probably late Pleistocene (last Ice Age, 40'000y).

 

Your little gastropod is too poorly preserved for me to confidently ID it but I think it might be Nucella lapillus. 

The oysters are Ostrea edulis, and the cockle is Cerastoderma edule. 

These are all modern unfortunately.

 

I hope this helps!

 

 

 

 

[acetabular]

Thank you so much for your help-- i appreciate it! I thought as much for the mammal bone chunks, though believe the smaller piece to be from a skull due to the trabecular structure. I am also confident that the other chunk comes from a long bone (perhaps radius? Certainly falls inside the possibilities of Bison) but that is a best guess.

 

I am grateful to learn about the shells! I had a feeling they were modern, but love the look of them (particularly the whelk).

 

Cheers!

[Max-fossils]

On 10/31/2021 at 6:39 PM, acetabular said:

Thank you so much for your help-- i appreciate it! I thought as much for the mammal bone chunks, though believe the smaller piece to be from a skull due to the trabecular structure. I am also confident that the other chunk comes from a long bone (perhaps radius? Certainly falls inside the possibilities of Bison) but that is a best guess.

 

I am grateful to learn about the shells! I had a feeling they were modern, but love the look of them (particularly the whelk).

 

Cheers!

No problem!

I'll be honest, your IDs for the mammal bones do seem somewhat like a long shot to me. They're definitely good guesses, but many other options would also be good guesses, and it's difficult to rule any of them out. So you could be correct but you could also be completely wrong; which I know is a very vague answer, but unfortunately that is typically how it is with bone fragments like yours  

And yeah, the shells do look nice! It's a shame people overlook them so often, I find that they're often quite pretty, and they're definitely much more diverse and interesting than most people give them credit for. 

Good luck on your next fossil hunts!

Best,

Max

[sjaak]

The verts are from bony fish as mentioned above. Probably Holocene.

 

The bone fragments are too fragmented for a proper ID. I have this rule of thumb for Zandmotor and other Dutch coast bones:

- black bones, not heavily fossilised: Early Holocene

- brown bones, that are sticky when touched with a wet finger: Pleistocene 

Then there are some Eemien bones but these are rare. These can be heavily fossilised with a lot of iron. Again, this is a rule of thumb and not a scientific way of determining the age.

 

I can’t help you with the shells.

[acetabular]

thanks!