Dear Gladys,
"subspecies are genetically isolated groups of populations ...which live in
different parts of the whole area ...occupied by the species." Simply
speaking, subspecies are groups of populations, which share certain shell
qualities with other populations of the same species, but partly differ from
them in one or several other shell characteristics. When comparing two
subspecies of the same species, we can expect that certain shell
characteristics of the majority of their individuals differ. But we must
remember that this is true only for the majority of individuals but not for
ALL individuals. This means that one can always find unusual shells in any
cowry population, which differ from the majority. When shell characteristics
of 100% of individuals in two groups of populations differ even in one shell
character without intermediate forms, we can separate such groups as
SPECIES.
Subspecies MUST be isolated geographically or ecologically (fossil taxa
are isolated stratigraphically, in time) otherwise the difference in shell
characteristics of their individuals will disappear owing to cross-breading.
So, shells which you have from Ascension I. are correctly identified as C.
acicularis sanctaehelenae and shells you collected in Bahamas belong to C.
acicularis acicularis.
I am very glad that you opened this question.
Questions like this are discussed from time to time in this forum, for
example: "I have a Cypraea tigris shell 117 mm long from Madagascar. Is it
C. tigris schilderiana?" C. tigris schilderiana is a subspecies from Hawaii
Is. and near-by areas and can not be found in Madagascar. This subspecies is
characterized by mostly very large shells but unusually large single shells
may be found in any population of C. tigris.
Best regards
Ed
----- Original Message -----
From: "Gladys Fehling" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Monday, October 21, 2002 5:07 PM
Subject: Re: Cypraea acicularis santeahelenae, Schilder 1930
> Dear Eduard,
>
> Thank you for your explanation of the differences in the two Cypraea
> acicularis shells. I'm sure the shell I have came from Ascension Island
as
> the person I got it from worked there on the test range and collected
shells
> there. He identified the shell as Cypraea acicularis sanctaehelenae. I
also
> have shells I collected from Andros Island Bahamas with the same markings.
> The shells I have from off the west coast of Florida do not have the dark
> markings. Would I then call the C.acicularis which I collected in the
> Bahamas C. acicularis sanctaehelenae?
>
> Thanks again,
> Gladys Fehling
> [log in to unmask]
>
>
> ----- Original Message -----
> From: "Eduard" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Monday, October 21, 2002 5:02 AM
> Subject: Re: Cypraea acicularis santeahelenae, Schilder 1930
>
>
> > Dear Gladys,
> > let me add more to your confusion and cite Prof. Schilder who described
C.
> > spurca sanctaehelenae:
> > "In the American acicularis ... the dorsum is fulvous to orange with the
> > lateral spots pale and less conspicuous than the ferrugineous lateral
> > pittings, while in sanctaehelenae ... from the Southern Central Atlantic
> the
> > dorsum is brown with the dark lateral spots relatively more acentuated."
> > So, the two subspecies, acicularis acicularis and acicularis
> sanctaehelenae,
> > are separated geographically and if you are sure that your shells were
> > collected in the Southern Central Atlantic (S. Helena I., Ascension I.)
> they
> > are undoubtedly acicularis sanctaehelenae.
> > Best regards
> > Eduard Heiman
> >
> > ----- Original Message -----
> > From: "Gladys Fehling" <[log in to unmask]>
> > To: <[log in to unmask]>
> > Sent: Monday, October 21, 2002 4:48 AM
> > Subject: Re: Cypraea acicularis santeahelenae, Schilder 1930
> >
> >
> > > Thank you,
> > >
> > > Now I am more confused than ever. I got exactly the opposite
> information
> > > from two other sources. Look at the following site:
> > > http://www.cypraea.net/aciculariscomparative.htm and you will see
what
> I
> > > mean. I also received photos from another individulal with the exact
> same
> > > information.
> > >
> > > Sincerely,
> > > Gladys Fehling
> > > [log in to unmask]
> > >
> > > ----- Original Message -----
> > > From: "Ringwald Fabien" <[log in to unmask]>
> > > To: <[log in to unmask]>
> > > Sent: Wednesday, October 16, 2002 7:44 AM
> > > Subject: Re: Cypraea acicularis santeahelenae, Schilder 1930
> > >
> > >
> > > > Hello!
> > > >
> > > > I believe that there are only two features that can
> > > > separate acicularis from sanctaehelenae.
> > > > First feature :
> > > > Acicularis aciularis: The marginal pitting is very
> > > > regular all along the margin; with generally a black
> > > > coloration in each depression of the pitting. This is
> > > > always right on the elder specimen and frequently
> > > > visible on younger specimens.
> > > >
> > > > Acicularis sanctaehelenae : the marginal pitting is
> > > > visible only near the extremities, even on the elder
> > > > specimens. No black coloration in the depressions of
> > > > the margins.
> > > >
> > > > Second feature :
> > > > The spots all along the margins are regularly arranged
> > > > along the margins, in the ac. ac. case, but they are
> > > > randomly arranged on the margins of ac. Sthelenae.
> > > >
> > > > I would like to stress on one point : the coloration
> > > > of the dorsum is absolutely not a constant feature.
> > > > This year, I found ten specimens in Martinique Island
> > > > which were really dark (nearly brown dorsum) and not
> > > > yellow at all. This almost depends of the biotope in
> > > > which a population of cowries lives.
> > > > Sincerely
> > > >
> > > > Fabien
> > > >
> > > > ___________________________________________________________
> > > > Do You Yahoo!? -- Une adresse @yahoo.fr gratuite et en français !
> > > > Yahoo! Mail : http://fr.mail.yahoo.com
> > > >
> >
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