fossil plant nomenclatural problem

[John McNeill]

I cannot see how the use of _Eucalyptus haeringiana_ for "species 2" can
be other than a tentative identification by Lesquereux of his material
as _Eucalyptus haeringiana_ Ettingshausen -- note the ? after the
species name -- if he was describing a new species, that happened to be
homonymous with Ettingshausen's, he would not have used a question mark.  So it
seems a tentative misidentification, not a homonymous species name and so cannot
be a basionym (and indeed does not have a "type") - and so _Palaeoaster porosum_
(Lesquereux) U. Sm. comb. nov. would seem to be the correct name.

But even if _Eucalyptus haeringiana_ Lesquereux (1873) is treated as a name
independent of  _Eucalyptus haeringiana_ Ettingshausen (1853), the result is the
same,  The later homonym is illegitimate, and so cannot provide the basionym for
a new combination.  Had he known of Lesquereux's material, Knowlton in 1918
might have used the name _Palaeoaster haeringiana_ but, even if he had
attributed the epithet to Lesquereux, the correct citation would have been
_Palaeoaster haeringiana_ Knowlton and its priority would have dated only from
1918.

Sorry not to quote the specific Articles from the ICBN, but I do not have my
copy handy -- but anyway it is on the Web.  Check for Berlin Bot. Garden, or
IAPT and take it from there.

By the way, the thought of confusing a (living) _Eriocaulon_ and a _Eucalyptus_
is mind-boggling -- fortunately I do not work on fossil fragments!

John McNeill

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  John McNeill, Director Emeritus, Royal Ontario Museum,
  100 Queen's Park, Toronto, Ontario, M5S 2C6, Canada.
  Tel. and fax # 416-586-5744  e-mail: johnm at rom.on.ca
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______________________________ Reply Separator _________________________________
Subject: fossil plant nomenclatural problem
Author:  Una Smith <una.smith at YALE.EDU> at Internet
Date:    15/12/1998 14:41


Here is a frustrating nomenclatural problem that I have been struggling to
resolve.

species 1:  Eucalyptus haeringiana Ettingshausen 1853
species 2:  Eucalyptus haeringiana? Lesquereux 1873     [note the "?"]
species 3:  Eriocaulon? porosum Lesquereux 1874
species 4:  Palaeoaster inquirenda Knowlton 1918        [new genus]

All four species are fossil plant organs (not complete plants).  Species 1
is from the Tertiary of Europe, and the others are from the Cretaceous of
North America.  Species 1-3 are in extant genera; species 4 is the type
species of its genus.  The type specimens of species 2-4 are clearly all
members of a single species, and don't belong in Eucalyptus or Eriocaulon.
(I doubt if species 1 belongs in Eucalyptus either, but that is not my
concern.)  Thus, a new combination is needed.

Here is my problem.  The correct generic name is Palaeoaster, but what is
the correct epithet?  Is it "porosa" from species 3 or "haeringiana?" from
species 2?  This depends on the application of current nomenclatural rules
to species 2.  Is species 2 just a misidentification, or a homonym, or a
proper name?  Lesquereux described species 2 from his own (type) specimen,
cited species 1, and was vague about whether he thought his specimen did or
did not belong in species 1.

What do you think?

        Una Smith                       una.smith at yale.edu

        Department of Ecology and Evolutionary Biology
        Yale University
        New Haven, CT  06520-8106