>Scott E Jordan wrote:
>>
>> Is there a reliable way to differentiate Cymbium cucumis Roeding, 1798
>> from Cymbium cymbium, L., based solely on shell morphology?  I can't
>> tell looking at Poppe and Goto.
>>
>> Regards,
>>
>> Scott Jordan
>T.E Eichhorst's answer is complete. Note that in most specimens
>C.cucumis have three columellar plaits and a rusty color, C.cymbium only
>two and a greyish color.We can also observe that Poppe & Goto pictures
>show likely two specimens of the same species: C.cucumis!
>In this genus, we have many transitional forms, the limits of
>specification is not always defined and a deep Revision is needed.
>Regards, Pat

I'm sorry that I've to react, but figures 5 & 6 are definitely C. cymbium,
they came from a lot of C. cymbium, but the choice of the specimen is not
good for that type of book. Indeed, the C. cucumis, nr. 4 is also not well
chosen. Most cucumis from nature resemble the cymbium in this book, and
most cymbium resemble the cucumis nr. 4. (apart for the colour that is
correct)
As Pat points out, there are many transitional forms, and the ones shown do
not clearly demonstrate the characteristics of both.
One has also to say that these are not easy shells, but I'm sure that if
one is playing a week with half a thousand Cymbium, things become clear int
he mind. Not so clear as between Cypraea talpa and Cypraea tigris, but well
defined. As with Clausilia (Joke)

Guido

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