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Olives: two doubtful specimens
05-24-2011, 05:10 AM,
#11
Re: Olives: two doubtful specimens
So now we have two supposed caroliniana: size is similar, I scanned the specimens with different enlargements but the specimen size is almost identical.

I may agree that O. caroliniana is a very variable species, and I wonder how this could be. But I must admit that the pictures at <!-- m --><a class="postlink" href="http://www.gastropods.com/4/Shell_4074.shtml">http://www.gastropods.com/4/Shell_4074.shtml</a><!-- m --> seem to cover both the morphs... You did a great job, bit deep in my heart I can't believe that variability is so extreme. I posted two new pictures with both sides of a single specimen coupled.

Supposed carolininana 1 (maybe somalia, not certain)
The one that you identified right from the start
<!-- m --><a class="postlink" href="http://www.badongo.com/pic/13030081">http://www.badongo.com/pic/13030081</a><!-- m --> (new image, two sides of the same specimen)
low, flat but pointed spire, last whorl higher (shoulder not exposed), columellar callus quite high, about 14 columellar folds, thick and prominent, mouth width almost constant.
Resembles very closely the pictures at <!-- m --><a class="postlink" href="http://www.gastropods.com/4/Shell_4074.shtml">http://www.gastropods.com/4/Shell_4074.shtml</a><!-- m --> except the first picture,

Supposed carolinnana 2 (madagascar, ampasilava, mozambique cannel)
The one identified by Mr. Monfils several months ago
<!-- m --><a class="postlink" href="http://www.badongo.com/pic/13030082">http://www.badongo.com/pic/13030082</a><!-- m --> (new image, two sides of the same specimen)
veri pointed and steep spire, spire inclined, last whorl lower (shoulder exposed), columellar callus quite low, columellar folds amost imperceptible, seemingliy "coupled" (a deeper sulcus seem to separe couples of folds), mouth distinctly narrower at mid-heigth
Resembles very closely only the topmost picture at  <!-- m --><a class="postlink" href="http://www.gastropods.com/4/Shell_4074.shtml">http://www.gastropods.com/4/Shell_4074.shtml</a><!-- m -->, including the few thin, vertical, transparent lines all along the shell.

I hardly believe that a species can be so variable. Many thanks, you did a great job!
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05-24-2011, 09:28 AM,
#12
Re: Olives: two doubtful specimens
I still think they are both caroliniana and yes, Oliva can be that variable, just look at O. vidua or even O. oliva. Both can vary in shape as well as colour.
Dave
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05-26-2011, 03:20 AM,
#13
Re: Olives: two doubtful specimens
Dear Dave:
For me, the question is set! I totally share your opinion.
Thank you very much, this was an useful lesson on variability.
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05-26-2011, 09:23 AM,
#14
Re: Olives: two doubtful specimens
It was my pleasure mate, I love a good discussion!
Cheers,
Dave
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