Re: camarasaurids; and more clarifications

["David Marjanovic" <david.marjanovic@gmx.at>]

----- Original Message -----
From: "Ken Kinman" <kinman@hotmail.com>
Sent: Thursday, October 18, 2001 4:37 AM


> [...] my Titanosauridae (sensu lato) is
> equivalent to "Titanosauria" which has been cladistically chopped up into
3
> (or more?) separate families (which I would probably recognize as
> subfamilies if I formally recognized subfamilies).

Not only these but also lots of single genera that you would call plesia if
you wouldn't allow paraphyletic taxa, plus lots of genera incertae sedis.

>       I should mention that the Kinman System does not *forbid* the use of
> formal intermediate ranks, but tries to strongly discourage it (unlike
> strict cladists who do *forbid* the recognition of *ANY* formal
paraphyletic
> taxa).

But _exactly_ like the PhyloCode that does not *forbid* the use of any
ranks, just says they have no real meaning and don't affect names.

> In any case, I think it is silly to give placozoans their own
> subkingdom----- but given their apparent uniqueness and deep placement in
> the Metazoan tree, a separate Phylum Placozoa seems justified [...]
>        KINGDOM METAZOA
> 1   Porifera
> 2   Placozoa
> 3A  Cnidaria
>   B  Petalonamata (extinct phylum)
> 4   Ctenophora
>        ..... and so on.

IIRC:
--+--Mycetozoa
    `--Opisthokonta
          |--Fungi(morpha)
          `--*--Choanoflagellata
               `--Metazoa
                     |--Porifera = Parazoa
                     `--+--*Trichoplax*
                          `--+--Cnidaria
                               `--+--Ctenophora
                                    `--Bilateria
(I included a few outgroups just to show that, contra Linnaeus, Metazoa
doesn't hang in the air.)
* Some call this clade Animalia, others synonymize Animalia and Metazoa. I
call for a definition.
I know next to nothing about Petalonamata (Petalonamae?).

Such a cladogram requires much less thinking IMHO, you can just look at it
and _see_ the relationships...

Would you unite sponges and *Trichoplax* as a paraphyletic Parazoa if you
would have kept the subkingdom rank? Or what?

>      And rather than name a new formal clade "Epitheliozoa", why not just
> call them non-Poriferan metazoans

good, but that becomes cumbersome sooner or later, remember "the
segnosaur-oviraptorosaur clade"

> (or epitheliozoans).
> [...]
> I'm not against giving names to such
> clades, but let's keep it informal, and save the formal names for the
> most-strongly supported clades.

Because this _strongly_ implies that there is a name Epitheliozoa somewhere,
and it will inevitably appear in print sooner or later by someone who has
read "epitheliozoans" too often. Such an artificial "informal" name is _just
the same_ as a "formal" one. You don't (can't) eliminate "intermediate
ranks", you just put them behind glass and pretend the glass is not
transparent while it is. (Sorry for the placative words, it's 23:25 and past
my bedtime too.)
(Epitheliozoa is a bad example because it is AFAIK little used. It is
apparently not needed that much. "Enigmosauria" is.)

> And with reference
> to the above coded classification in particular, you can refer to it as
> clade Metazoa 2+ (epitheliozoans).

As long as everyone has a classification lying before them to look up where
the 2 sits, and until one morning you change the coding.