Saturday March 20, 1999 11:46 AM
Dear Friend,
I would like to thank Thomas E.Eichhorst, Paul Callomon
and Fred Vervaet which answered to my old message.
Obviously I was joking writing :...and in the meantime I don't know
what to write on the labels of many Olives which I own.
This is the last between the problems I have collecting these
shells. The real problems come from their intraspecific
variability. There are two kinds of this variability:
A) In this first type many color forms of the same species live
all together in the same place. For instance if you are
looking for Oliva bulbosa Roding, 1798 to Zanzibar Is.,
Tanzania (East Africa) you surely will find all its color form
as bicingulata, lacertina, fabagina, undata, aurata, immaculata
tuberosa and inflata. But you surely will find also many
intermediate color forms. The same is for Oliva oliva Linnaeus,
1758 or Oliva fumosa Marrat, 1871 and many other species.
In this case only the colors, the pattern and the size change.
B) In this second type each color form of one species live in
different locality. And each color form (or perhaps subspecies ?)
makes an homogeneous population where each specimen is
very similar to the others. This is the case of Oliva reticularis
Lamarck, 1811 (East Central America) and Oliva spicata
Roding, 1798 (Western Central America). For instance the
specimens of spicata which live on Coronado Is. ( Middle of
Gulf of California) are very different from the ones which live
on Balandra Bay (South of Gulf of C.) and both are very, very
different from the spicata which occours in Panama's waters.
I think also Oliva miniacea Roding, 1798 , the Red-mouth
Olive, shows this kind of variability. Indeed there are red-mouth
where the red is...grey, cream, light blue and also...white !!
In these Olives all seems to change : the pattern, the color,
the size and also the shape (or outline).
It's in this last kind of variability that I feel the necessity to identify
clearly each population waiting for someone finds if they are the
same species, subspecies or simply color forms.
Warmest regards to all, Maurizio.
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Maurizio A. Perini
Via Pedrazza, 9
I - 36010 Zane (VI)
I T A L Y
Voice +39.0445.380378
F A X +39.0445.384784
e-mail [log in to unmask]
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