Re: The Papers That Ate Cincinnati

["T. Michael Keesey" <keesey@gmail.com>]

On 5/5/07, Tim Williams <twilliams_alpha@hotmail.com> wrote:
> A stem clade "Panopisthocomiformes" could be erected for all birds closer to
> the hoatzin (_Opisthocomus hoazin_) than to any other modern bird.  It might
> include such fossil taxa as _Hoazinoides_ and _Foro (if not a
> musophagiform), though probably not the highly dubious _Onychopteryx_.

Presumably the panclade name would be _Pan-Opisthocomus_ or
pan-Opisthocomus or something along those lines. It would be
permissible, e.g., to define _Opisthocomus_ as "_Opisthocomus hoazin_
and all of its descendants". (Although I've never seen anyone propose
a definition like that, it would yield a crown clade with the same
currently extant content as the species.)

Or we could simply leave it unnamed for now and refer to the total
group of hoatzins or stem hoatzins or whatever.

Alternately, you could use _Opisthocomiformes_ for the total group.

> The alternative is to make Opisthocomiformes apomorphy-based,
> as Clarke et al. (2003) suggested for Sphenisciformes.

Not a bad idea, either. (With the character of manual unguals in
juveniles, perhaps? Or digestion by fermentation in the crop?)

--
Mike Keesey