It is not clear that the case of Dentiscala nesiotica and Asperiscala
nesiotica is one that would cause confusion. Are both considered to be valid
species? If not there is little possibility of confusion. Were they both
named in the same genus, or did they start out in separate genera? What are
the authors and dates of the species?
 
 
On a related note, here is the text of several Recommendations in Appendix
D(I) of the International Code of Zoological Nomenclature.
 
3. A zoologist should not publish a new genus-group name that differs from
other such names only in its termination or in small differences in
spelling, e.g., Hygrobia, Hygromia; Leucochile, Leucochilus; Merope, Merops;
Odhnerius, Odhneria, Odhnerium; Peroniceras, Peroniceras; Sciurus, Seiurus.
 
5. A zoologist should not publish a new species-group name
(a) identical with one already in use in a closely related or associated
genus -group taxon, or
(b) that differs from such a name only in its termination or in small
differences in spelling, e.g., fluvialis, fluviaticus, fluviatilis;
furcifera, furcigera; granulatus, granulosus; marginalis, marginatus.
 
6. A zoologist should not base a new species-group name on a personal or
geographic name if another name derived from the same word is in use in the
same or in an allied or associated genus, e.g., hispanus, hispanicus;
moluccensis, moluccanus; sinensis, chinensis; ceylonicus, zeylanicus.
 
7. A zoologist should not choose a new species-group name differing from one
in the same or in an allied or associated genus in being an adjective
instead of a noun or vice versa; this applies also to the terminal element
of a compound name, e.g., cauda (noun): caudatus, -a, -um (adjective);
crassicosta: crassicostatus, -a, -um.
 
These are recommendations rather than rules, because there are too many
differences of opinion as to how similar is too similar. One author would
change a name, saying it is too similar, another would refuse to use the
change as being unnecessary. For the sake of stability of nomenclature,
perhaps at the cost of occasional confusion, the rules allow even a single
letter difference to be sufficient in most cases.
 
Gary
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Gary Rosenberg, Ph.D.                     [log in to unmask]
Malacology & Invertebrate Paleontology    gopher://erato.acnatsci.org
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