Evolute ammonites from Madagascar

[Ailanna]

Total newbie here. I'm trying to catalog my ammonite collection and have a few pieces that I just can't seem to figure out. Both of these are evolute ammonites. Each has a bit of remaining iridescent nacre near the umbilicus, which is why I think they're likely Cretaceous fossils from Madagascar. The outermost spiral of the larger one has considerable girth (27 mm across the squared off end), while the smaller one is pretty uniform (9mm at the squared off end) and almost wholly agatized. The small one came from a rock shop in Northern California (Chapman's), and the larger one came from online; both claimed to be from Madagascar. I know some of the diagnostic characteristics have been polished off, but I'd really love to know at least what family or genus these are. 

 

Thank you very much for your help! Er...I might have more mystery ammonites after this. Is it less annoying to put them all into one post, or spread them out over a few weeks? 

[caterpillar]

Take a look to Eogaudryceras

[Walt]

It is easier if you break up your ID requests into separate posts...Or maybe a couple to a post.  Not necessary to wait weeks, but the separate posts are easier for folks to examine and comment on.  Too many requests in the same post leads to confusion

 

And welcome to the forum!

[Ailanna]

33 minutes ago, Walt said:

It is easier if you break up your ID requests into separate posts...Or maybe a couple to a post.  Not necessary to wait weeks, but the separate posts are easier for folks to examine and comment on.  Too many requests in the same post leads to confusion

 

And welcome to the forum!

Good to know. Thank you! I can try to lump them by broad geographical origin...got a couple of puzzlers from Morocco as well.

[Ailanna]

42 minutes ago, caterpillar said:

Take a look to Eogaudryceras

That looks like a good possibility. Thanks!