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NOMENCLÁTOR OF GASTROPOD FAMILIES
Part 1. NOMENCLÁTOR OF GASTROPOD FAMILY-GROUP NAMES
A Summary of the Rules of Nomenclature
Applying to Family-Group Names
The International Code of Zoological Nomen-
clature (ICZN) defines the family group as in-
cluding the taxa "at the ranks of superfamily,
family, subfamily, tribe, subthbe, and any other
rank below superfamily and above genus that
may be desired" (Art. 35.1). The Code does
not regulate the names of taxa above the fam-
ily group (sometimes termed the class group),
but family-group names are fully subject to the
provisions of the Code, which determine
among others how the names shall be formed,
their availability, and nomenclatural validity.
Whereas some rules apply to all names in the
species, genus and family groups, other rules
apply specifically to family-group names. As
these rules are sometimes little known or misunderstood,
it may be appropriate to summarize
how they affect family-group names.
Availability of Names
Articles 10-20 determine the conditions of
availability of scientific names. Of specific relevance
to this nomenclátor of family-group
names are Arts. 11.7 and 13.2, which state
that:
(1 ) "A family-group name when first published
[...] must be a noun in the nominative plural
formed from the stem of an available generic
name [...]; the generic name must be a name
then used as valid in the new family-group
taxon"[Art. 11.7.1.1].
Examples:
Because Phobalea is not an available ge-
neric name, the name Priobaleinae A. J.
Wagner, 1922, is not an available name.
The name Gymnosomata Blainville, 1824,
established as a family, is not available as a
family-group name because it is not formed
from a genus name. (This does not affect its
availability by those who want to use it above
superfamily, as such names are not regulated
by the Code).
Da Motta (1995) established the name
Textiliinae, based on "Cylindrus [sic! = Cylinder]
Montfort, 1810 as the type genus" and
treated Textilia Swainson, 1840, as a synonym
and thus not as a valid name. Under
Art. 11.7.1.1 of the Code, Textiliinae is not
an available name.
(2) "A family-group name when first published
must [...] be clearly used as a scientific name
to denote a suprageneric taxon and not
merely as a plural noun or adjective refer-
ring to the members of a genus" [Art.
11.7.1.2].
Two cases need to be discussed here: da
Costa's family names and Troschel's names
established as plurals.
Da Costa (1776) appears to have been the
first author who used the word "family" in a
classification of the molluscs, and these
names require specific discussion. Da Costa
subdivided the shelled molluscs into three
divisions: Univalves, Bivalves and Multivalves.
Each division was further subdivided
into orders, sections (in one order of bivalves
only), and families. Shelled molluscs {sensu
da Costa) consisted of 32 families, of which
16 families are "Univalves" (i.e., gastropods,
scaphopods and cephalopods). Some of the
family names (Patella, Haliotis, Cylindri,
Voluta, Cassides, Trochi, Buccina and
Murex) are Latin names, apparently formed
on a stem-genus, and it is necessary to discuss
their availability under the Code. First,
it should be noted that da Costa uses cer-
tain generic names with a meaning radically
different from that of his contemporaries. For
instance, da Costa uses "Voluta or Volute"
for species of Conus, but the only species
of Volutidae illustrated by him is identified
as the "Melon Tun" of the family Globosa.
Da Costa's Strombus is a fasciolariid,
whereas he illustrates a species of Strombus
as "A Murex of the Alata genus". Second, da
Costa's family names are most frequently
formed by the first word of polynominal ge-
neric names. For instance, the family Cylindri
contains two genera, Cylindri emarginati and
Cylindri marginati. The family Buccina contains
six genera: Buccina Canaliculata,
Buccina Recurvirostra, Buccina Rostrata,
Buccina Umbilicata, Buccina Columella
dentata vel plicata, and Strombus [a
fasciolariid, see above]. Other names, such
as Turbinata involuta, Auris Cochlea,
Globosa, Cochleae, and even Voluta, are
plurals not based on a genus. In conclusion,
even in the context of his time, da Costa's
usage of family and genus names is inconsistent
with the principles of Articles 4.1 and
11.7.1 .2 of the Code. It seems best to inter-
pret Da Costa's family names as plural