Hi to all,
 
 
to clear things up a little:
 
- tangaroana is the very deep water New Zealand Pleuro
- westralis are the Australian ones
 
The differences, not the "scientific ones":
you can differentiate them at once by the different colour: tangaroana is
always white, with a very pearly shine in the shell. Almost all shells
known are young specimens, small size. I know of only one big shell with a
whole in it in the Widodo collection.
 
Westralis is cream, very light, to almost solid orange.
 
"In the beginning" tangaroana was named first. But then turned up by the
thousands the Australian one without a name. So many people called this one
tangaroana. Even now, hundreds of wrongly identified westralis are labeled
"tangaroana".
 
Now, everybody expected the westralis to be named fast, but no, it took a
couple of years between the first findings and somebody who got the good
sense to describe it. Exactly as some shells now, in collections for
years,and no name because people take years to describe it. When one finds
an elephant with the neck of a snake, and he finds ten of it, the young,
the oldest etc... then fast action should be taken to avoid confusion with
existing things and the beast should be described.
 
Of course, the group of africana slit shells can be approached in different
ways: with present knowledge, one can separate easily africana, teramachi,
westralis into valid species. Tangaroana and diliculum are a little further
but also belong to this group.
 
But instead of considering these valid species, one can also think they are
all subspecies of one species. Depends on how you look at it.
 
The differences between all these are mainly sculpture, little colour
variation, and little shape variation.
 
For easy way of life, I adhere to the view of Anseeuw and Goto, who are
probably right  in  considering them valid species.
 
Now, all the above is not scientific, but a realistic 19th century view on
shells I'm happy to live with.
 
Best regards, Guido
 
Nice surprise: a non-described one is living in the deep around New Caledonia.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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