Snail Of Unknown Origin

[wolf1]

Hi,

unfortunately, I’ve got another very problematic specimen here without any data. Sad enough…… . Hight 46, width 57 mm (1,81 and 2,24 inch). It reminds me of Trochidae, genus Trochus. The aperture seems to be rather oblique, so Turbinidae should be less likely, I think.

Thanks for any guess…… . Kind regards: wolf

Frontal view:

Basal view: spiral lines near umbilicus

[Wrangellian]

It could be either in my non-expert view - The shell guides I have show some Turbans with oblique apertures like this. Sorry to not be able to narrow it down for you.. I hope there are others who can!

[wildernessmd]

I agree with your assessment that this is probably not of the Turbinidae Family due to your description of the aperture. I too believe it is probably of the Trochidae Family and the Trochus genus. However now it gets a bit more complicated as to the species, as there are well over 20 species identified within the genus Trochus. As far as the species, it is best to have a specimen "in-hand" to do a species identification so I'm sorry I can't help you there, but from the two photos and the information you provided I would "tentatively" identify this specimen (based on other specimens I have seen, the pattern near the umbilicus and the sharp apical region of the specimen) as a Trochus niloticus, possibly a juvenile specimen due to the size. I'm sorry I couldn't be a bigger help, good luck - nice specimen! Cheers! Mike

[wolf1]

Hi Wrangellian and Mike,

thanks a lot for your time and trouble and for confirming my diffuse guess.

I got some recent Trochus niloticus here, but the specimen pictured here seems to be grounded / polished , and that makes it extremely difficult. Thanks again: wolf

Edited June 16, 2013 by wolf1

[jam85]

Bathrotomaria species, family Pleurotomariidae. Unit and age: unnamed iron-oolitic limestone, Morondava basin (Oxfordian Stage, Jurassic). Quarry west of Sakaraha, Atsimo-Andrefana Region, Madagascar.

These fossils are frequently polished, unfortunately.

James

Edited June 16, 2013 by jam85

[wolf1]

Phantastic….. . Thanks a lot for your extremely detailled input. I never thought this would be possible in this particular case….. . Thanks again, kind regards: wolf

[Wrangellian]

Aha, You can usually count on getting an ID for something that is available on the market.. there is always someone out there who has the same thing but with data... I had never seen one myself!

[wildernessmd]

Hmmm, jam85 has a point, it COULD be from the Family Pleurotomariidae, Bathrotomaria species, it sounds like he probably has one that has been identified before. Without having it in my hand, and since it is polished, this is debatable, I still question the apex of the shell, was it like that originally or did it become that sharp an apex due to polishing so I defer to others! Identifying fossils is always a challenge especially when they have been altered by polishing or poor conservation. I am much better at human osteology, especially teeth, skulls, etc. When I have problems identifying a shell specimen but have a clue where to start (ie: Family, Genus), I go to the "Shell Encyclopaedia" from Conchology, Inc. at: http://www.conchology.be/?t=64 - maybe this will help you Wolf, now (and in the future). It's a bit commercial (which I ignore) but they have decent photos of specimens. Shells are not my area of expertise by any means! Nice to read all the great input, I always learn something new! Mike

Edited June 17, 2013 by wildernessmd

[wolf1]

Hi Mike,

thanks a lot for your post and the link to Poppe (conchology.be). I go to that site sometimes in search of recent species, but I wasn't aware of his fossile species yet. Concerning living gastropods I normally go back to the original descriptions or to latest revisions, as far as available, but I know just nothing about fossil species........ .

So thank you very much, kind regards: wolf