Dear Paul,

ICZN rules do apply to family(-group) names: articles 35-41.
Family names should have ending -idae (subfamily names -inae), and in order
to be available, they must follow requirements. For family-group names
these are:
(art 11 f (i) ) that it must
(1) be a noun in the nominative plural, based on the generic name then used
as valid for a genus contained in that family group taxon either by express
reference or by inference in context from the formation of the family-group
name; and
(2) be clearly used to denote a suprageneric taxon and not merely as a
plural noun or adjective referring to the members of a genus; and
(3) end in a latinized suffix (...)
(4) not be based on certain names applied only to fossils and ending in
-ites, -ytes, or -ithes.

Potamididae was derived from Potamides.
Personidae is based on the family-group name Personina Gray, 1854, which
was based on the genus name Persona Montfort, 1810.
ICZN 11 f (ii) A family-group name of which the latinized suffix is
incorrect is available with its original authorship and date, but with a
corrected suffix.

The genus name Persona was in use during Gray's days. Only later on it
turned out that Distorsio was erected by Röding (1798). Distorsio sensu
Röding however also contained some species now placed in Nassariidae.

The taxon (genus name in this case) Distorsio was clearified (by subsequent
designation) by Pilsbry as late as 1922. He made the type Murex anus
Linnaeus.
The taxon Persona was clearified much earlier, as Montfort mentioned only
one species in Distorsio, viz. Murex anus Linnaeus, by monotypy.

The family-group name Distorsiinae was erceted by Kuroda, Habe and Oyama in
1971, and subsequently corrected by Beu into Distorsioninae (1978).
The family name was not "chosen". There was no choise: the name Personidae
is older, available, and therefore has priority over Distorsionidae.
The same counts (more or less) for Cymatiidae: Ranellidae is older and
should be used.

Gijs


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> Van: Monfils, Paul <[log in to unmask]>
> Aan: [log in to unmask]
> Onderwerp: Re: Terebellum
> Datum: donderdag 2 september 1999 16:30
>
> A couple of questions about family names:
> I don't think ICZN rules apply to family names?  Is that right?  Yet
family
> names almost always seem to be derived from a genus name within the
family.
> Is this just sort of a tradition, or are there any rules or guidelines
> governing it?  What about a family name like Potamididae?  As far as I
know,
> there is no genus name that is similar.  Where does such a name come
from?
> One last question - when it was decided to divide the Cymatiidae into two
> families, why was Personidae chosen for the other family, given that
Persona
> is no longer a valid genus name?  Why wasn't it called Distorsiidae,
after
> Distorsio, the current and valid equivalent?
> Paul M.