> I'd go one step further and abandon the name Troodontidae as well -
> and revert to using Saurornithoididae as the name for this clade. I
> know it's permissible to retain family-level taxa founded on nomina
> dubia (we still use Ceratopsidae, after all). But I still don't think
> it's a good idea (I also think the name Ceratopsidae should be
It's not "permissible", it's required unless the family name is itself a nomen dubium, which is not automatically the case.
It's not like you get any choice in this matter as long as you stick to the ICZN. As long as the holotype tooth of *Troodon* fits the diagnosis of whatever "family" *Saurornithoides* belongs to and not that of any other "family", the name Troodontidae is valid and and Saurornithoididae is one of its junior synonyms. That's why Ceratopsidae and, yes, Titanosauridae are here to stay.
> As a nomen dubium, _Troodon_ would not be a genuine OTU
> (operational taxonomic unit),
OTU just means "line in a data matrix". Several specimen-level phylogenetic analyses (of other clades) have been performed.
Thomas R. Holtz, Jr.
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