Taxacom: Collective groups and form(al) genera

[Paul van Rijckevorsel]

There is a textual issue with Article 42.3.1: "Collective groups have no 
type species."
This implies that taxa, starting with genera and subgenera, do have 
types. Obviously, taxa and other groupsof organisms (or parts of 
organisms)never have types; it is names, or in the zoological /Code/ 
"nominal taxa" (whatever they are), that have types, so 42.3.1should run 
something like: "Names of collective groups have no type species."(is 
there such a thing as a "nominal collective group"? And if not, why 
not?)or"The application of a name of a collective group is not 
determined by reference to a type species." The latter (mirroring 42.3) 
may be the more accurate, given what is in 67.14. Paul
On 25/06/2025 03:50, Ziv Lieberman via Taxacom wrote:
> Hi all,
> I'm thinking about the differences between "form" or "formal genera" and
> "collective groups" and how to best approach these entities when
> establishing new nomenclature.
> In ants, there are many groups of fossil taxa which have been established
> for convenience, without implying that they form a natural group - mostly,
> e.g., impressions of wings or incompletely preserved fossils which can be
> associated based on one or more morphological features. Authors generally
> state that these are "form genera" (or, perhaps confusingly, "formal
> genera", especially in the Russian school of paleontology). However, they
> are nomenclaturally treated as "real" genera, including in that they have
> type species.
> To my understanding, these "form genera" align with the Code's definition
> of collective groups: "An assemblage of species. . .that cannot be
> allocated with confidence to nominal genera. Names proposed or used for
> collective groups are treated as genus-group names but special provisions
> apply to them". These provisions are given in 42.2.1 ("The names
> established expressly for certain assemblages of taxonomic convenience
> known as "collective" groups. . .established at the genus-group level are
> to be treated as genus-group names in the meaning of the Code." 42.3.1
> states "Collective groups have no type species."
> Therefore, I arrive at the conclusion that even though many "form(al)
> genera" are "established expressly for assemblages of taxonomic
> convenience", they are *not* collective groups, since they have type
> species.
> This leads to my direct question: If I want to establish a new collective
> group, should I follow 42.3.1 and not fix the name to a type species? This
> seems like it must be the right answer, but I am hesitant because I have
> never seen an example of such a name in practice.
> Further, if the type species of a form genus is transferred to a type-free
> collective group, are there any additional complications to consider?
> Thank you!
> -Ziv
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