G'day from Australia.  I'm just about to get on a soapbox, so be warned!
 
>Subclass:
>Order: Archaeogastropoda
>Super family: Pleurotomarioidea
>Family: Pleurotomariidae
 
Shouldn't we be making the transition from the old and uninformative
classification of Prosobranchia - Opisthobranchia - Pulmonata to a more
informative classification that reflects true relationships between the
gastropod groups?  In this case, the pleurotomariids would belong to:
 
subclass Orthogastropoda (includes all the gastropods EXCEPT the true
limpets)
 
superorder Vetigastropoda (Pleurotomarioidea, Fissurelloidea, Trochoidea,
Seguenzioidea)
 
superfamily Pleurotomarioidea etc etc
 
 
Prosobranchia should be discarded as it forces together a bunch of snails
that are not necessarily closely related.  Architectonicids, for example, are
traditionally placed in Prosobranchia, but are more closely related to sea
slugs and land snails than they are to cones and cowries and trochids.
 
Archaeogastropoda, too, should be ditched as it includes at least three
separate groups: the Patellogastropoda (true limpets), Neritopsina (nerites
and their relatives) and the Vetigastropoda (+ hydrothermal vent limpets).
 
"Mollusca: the Southern Synthesis" provides a good precis of this
classification.  For the more dedicated there's Ponder, W.F. & Lindberg, D.R.
(1997).  Towards a phylogeny of the gastropod molluscs - an analysis using
morphological characters.  Zoological Journal of the Linnean Society 19(2):
83-265.
 
That's enough of that for the morning.  I need some coffee.
 
Bronwen
 
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Dr Bronwen Scott                        School of Life Sciences
Lecturer, Invertebrate Biology          Victoria University of Technology
                                        St Albans Campus - S008
Phone: +61 3 9365 2443                  P.O. Box 14428
Fax: +61 3 9365 2465                    Melbourne MC
                                        Victoria 8001, Australia
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