Pete,

You bring up an excellent point -- and also one that is problematic.

When, as in the case of Amphidromus poecilochrous, an island population is pure or unique, the population may justify a subspecific name.  There are many examples of this on archipelagos with hundreds if not thousands of islands as in Indonesia and the Philippines.  It depends on how unique the population is from other populations within the range of the species.  Having a full picture of all forms of a species and knowing their distribution and geographical relationships helps to sort out questions of subspecific designation.

The catch here is documentation -- verified locality data.  Are we using reliable locality data and shell morphology to identify a shell, or just the shell characteristics to place a locality on the shell -- simply put, are we identifying the species or the locality?

Certainly the basic locality of the Adonara and Lombata forms of Amphidromus poecilochrous can be determined just by shell color and pattern because they are unique (or are they?).

If you compare color and pattern of the Lombata Amphidromus to the Komoto Amphidromus poecilochrous (subsp. jaeckeli) the range of color and pattern are amazingly similar.  Of course, they can be immediately differentiated by the shell density -- the Lombata Amphidromus are smaller, thin and fragile whereas the Komoto shells are consistently larger, and more solid.  Both islands are separated by the entire length of Flores Island (~ 350 km.) with no similar forms found on Flores.

Is this an example of parallel evolution? Uniqueness can only be determined by having a full picture of a species complex, which comes with verifiable locality documentation.

Amassing a collection of beautiful shells is one thing.  Holding a handful of undocumented shells and determining its locality based on look and then determining its taxonomic status is, to me, rather problematic.

Rich
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www.worldwideconchology.com
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---- Original message ----
>Date: Thu, 6 Mar 2008 21:03:44 -0500
>From: Pete Krull <[log in to unmask]>
>Subject: Re: [CONCH-L] amphidromus poecilochrous
>To: [log in to unmask]
>
>One more thought on Mr. Dharma's new Amphidromus names. I was at the St Pete
>shell show a week ago and a friend brought in a bag of Amphidromus with no
>data. They were obviously A. poecilochrous.  I had Dharma's publication and
>with that we were able to identify not only the name but also the specific
>island where the shells no doubt came from. Without Dharma's work we would
>have had a name but we could not have determined which among a group of
>islands the shells came from.
>
>Land snails living on a tropical island, or other geographically isolated
>location,  may very well deserve at least a form name, if not subspecific
>status, if the colony has any characteristics that set it apart from
>colonies in other locations. The description should, of course, point out
>those identifying characteristics. So, in effect, we'd be naming a colony as
>opposed to a specific shell.
>
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