The name Eucrassatella illustrates a method of naming new genera that is now
little used. "Eu-" means "true," and taxonomists in the old days sometimes
used it as a prefix to name the subgenus that they considered to be the
"true" or "core" subgenus of a genus. Later, as the rules of nomenclature
stabilized, it was realized that this procedure just added an unnecessary
complication to the system. Instead of subgenus Eucrassatella being the
"true" part of genus Crassatella, subgenus Crassatella is the "true"
Crassatella. So "eu-" is often untrue!

On another subject, David Campbell wrote,
"Incidentally, a Pliocene Eucrassatella (E. virginica) from Virginia seems
to be the first figured (Lister, before the Chesapecten jeffersonius and
Ecphora quadricostata) and first described (Gmelin) fossil mollusk for the
U.S."

This is intriguing. Is this based on prior publication, or simultaneous
publication on subsequent pages of one paper ("page priority")? Agreeing
with the ICZN, I don't recognize page priority as a valid principle, but
it's still neat to know about the first U.S. fossil mollusks to be figured.
The Paleontological Research Institution chose the Ecphora (a very beautiful
snail) as its emblem for this reason.

Andrew K. Rindsberg
Geological Survey of Alabama