Bivalves from Madagascar

[Max-fossils]

Hi everyone,

 

I went to a small rock shop some time ago and bought these three fossil bivalves. Unfortunately, the only information they had on them was that they were from Madagascar. 

More importantly than the species, I'd really like to find out a more precise location and age (including formation) for them. 

There were 6 shells available in the shop (all clearly from the same location). 4 of them were #1, then #2 and #3 were unique. 

 

#1: I think it's something from the Mactridae family. 

[Max-fossils]

#2: this one is an ark shell (family Arcidae). 

[Max-fossils]

 

#3: and this one is either something from the Astartidae or from the Veneridae.

[Max-fossils]

[Max-fossils]

The matrix is prepped off now, but I kept it on in these pictures so that someone might recognize it. 

I'm thinking these shells are probably from the Cenozoic, but whether they're Eocene, Pliocene, or somewhere in between I can't say. 

I tried googling some stuff but always end up on those horrible polished bivalves for sale at ridiculous prices... Only thing I did find is a paper on sharks and rays from a Miocene location called Nosa Makamby, where they do mention that there were lots of fossil shells there (but they don't show a picture of them so I can't tell whether the preservation is the same). 

So please, if you know anything about these shells (whether it's the precise location, their age or the formation), let me know too!

Thanks in advance,

Max

[Tidgy's Dad]

Can't help, I'm afraid, but they're pretty nice and unspoiled unlike a lot of stuff from Madagascar. 

It's always very hard getting exact locations, never mind formations from there, I have several specimens, including a Rastellum carinatum, but it's very hard getting precise details. 

 

[Max-fossils]

4 minutes ago, Tidgy's Dad said:

Can't help, I'm afraid, but they're pretty nice and unspoiled unlike a lot of stuff from Madagascar. 

It's always very hard getting exact locations, never mind formations from there, I have several specimens, including a Rastellum carinatum, but it's very hard getting precise details. 

 

That was my first thought too: "untampered fossil bivalves from Madagascar in decent condition? I'll take 'em"

I also did realize that finding accurate info for these shells would be really difficult, but I'm posting them nonetheless in case I get lucky and some awesome person can tell me more on them. I actually asked the shopkeeper if she knew anything more about the shells, and she admitted honestly that she just bought them from Madagascan dealers who themselves bought them from other dealers who bought them from collectors, and that in the whole transaction all the accurate information often gets lost. 

I've got that Rastellum carinatum too, very cool and weird oyster shell. But I doubt that they're from the same sediments... 

[FossilDAWG]

@MikeR may be able to offer some guidance.

 

Don

[Tidgy's Dad]

14 minutes ago, Max-fossils said:

That was my first thought too: "untampered fossil bivalves from Madagascar in decent condition? I'll take 'em"

I also did realize that finding accurate info for these shells would be really difficult, but I'm posting them nonetheless in case I get lucky and some awesome person can tell me more on them. I actually asked the shopkeeper if she knew anything more about the shells, and she admitted honestly that she just bought them from Madagascan dealers who themselves bought them from other dealers who bought them from collectors, and that in the whole transaction all the accurate information often gets lost. 

I've got that Rastellum carinatum too, very cool and weird oyster shell. But I doubt that they're from the same sediments... 

I doubt it at well. 

It's the same problem here in Morocco with details being lost along the line. You end up with nothing except maybe 'Erfoud' which is often not accurate anyway. 

Good luck! 

[Max-fossils]

Just now, Tidgy's Dad said:

I doubt it at well. 

It's the same problem here in Morocco with details being lost along the line. You end up with nothing except maybe 'Erfoud' which is often not accurate anyway. 

Good luck! 

Yeah it's annoying when this kinda stuff happens  

Thanks anyways