>1.  In order for a shell to become a paratype, does it have to be
>mentioned in the paper or book which first describes the species?
 
No. The International Code of Zoological Nomenclature (ICZN) says:
"Recommendation 72B: External evidence admitted.--If an author, in
establishing a nominal species-group taxon, does not explicitly state what
specimens constitute the type series, evidence in addition to published
evidence may be taken into account (e.g., labels by the original author and
specimens known to have been in appropriate collections at the appropriate
time.)
 
"Appropriate time" to me means "before the final version of the description
was submitted for publication". Thus, specimens that might have helped form
the author's published concept of the species are part of the type series,
unless the author explicitly excluded them. ICZN Article 72b has sections
discussing how specimens may be excluded from the type series.
 
72(b)i: "The type series of a nominal species-group taxon consists of all
the specimens eligible to be name-bearing types...included by the author in
the nominal taxon, except any that the author expressly excludes from the
type series [Subsect. (vi)], or refers to as distinct variants (e.g., by
name, letter, or number), or doubtfully attributes to the taxon."
 
72(b)vi: "If an author in establishing a nominal species-group taxon
nominates syntypes (or "cotypes" or "types"), or a holotype and
paratypes...and also lists other specimens, the separate mention of the
latter expressly excludes them from the type series."
 
>2.  If so, what information is required for a paratype description?
>
>3.  What are paratype numbers used for and are paratypes required
>having them?
 
Often paratypes are assigned numbers (paratype 1, paratype 2, etc.) for ease
of reference, but numbers are not required.
 
 
All sorts of odd situations can arise with type series. For example,
paratypes do not have to come from the type locality, but the original
author might have considered the type series to be only the material from
the type locality. If the specimens from other localities were not
explicitly excluded, they are part of the type series, despite the author's
intentions.
 
Paratypes can be misidentified--they do not have to be the same species as
the holotype. Sure misidentification is rare, but it does happen.
 
Sometimes specimens distributed by the original author are not types.
Occasionally an author will send us as a paratype a specimen collected after
the species description was published. Such a specimen is not eligible to be
a paratype, and is merely a specimen identified by the author.
 
Gary
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Gary Rosenberg, Ph.D.                     [log in to unmask]
Malacology & Invertebrate Paleontology    gopher://erato.acnatsci.org
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