Taxonomic issues

BYU ESM-163R is not the holotype of Othnielosaurus consors (Marsh, 1894). That specimen was initially described by Galton & Jensen (1973) as Nanosaurus (?) rex, significantly postdating the establishment of Laosaurus consors Marsh, 1894. The holotype of O. consors is YPM 1882 in the Yale Peabody Museum. The later change in genus name for this species does not result in a change in holotype, which remains fixed for the species.

I do not understand why the author states that Parksosauridae Buchholz, 2002 has taxonomic priority over Thescelosauridae Sternberg, 1937. The latter clearly has priority for the family-level group including Thescelosaurus. The fact that Parksosauridae received a phylogenetic definition prior to Thescelosauridae is irrelevant. Per Article 7.1 of the Phylocode, "Establishment of a name [in the sense of phylogenetic definitions] can only occur after the publication date of Phylonyms: a Companion to the PhyloCode, the starting date for this code"; i.e., pre-Phylonyms definitions do not compete for priority. As the nomina in question are family names they are subject to ICZN regulation, which grants Thescelosauridae priority. Potential use of Parksosauridae as a more inclusive clade containing Thescelosauridae is also against ICZN regulations; if a more inclusive stem-group containing a node-based Thescelosauridae is desired by ornithischian workers, a non-family-level taxon should be utilized for this clade.

This paper does not utilize the name Jeholosauridae except in reference to a hypothesized clade consisting of Jeholosaurus, Changchunsaurus, and Haya, which is not recovered in the current analysis. However, Jeholosauridae is a stem-based group anchored on Jeholosaurus, so it continues to exist in the absence of the other genera. In the current analysis, Jeholosauridae has changed composition to consist of Jeholosaurus + Yueosaurus.

waiting for moderation
1 Answer
Accepted answer

1) The holotype specimen of Othneilosaurus consors is YPM 1882, not BYU ESM-163R as stated in this paper. This was a simple error on my part. The taxonomic history of this species is complex, but I apologize for the mistake. This error does not impact any of the analyses or conclusions presented in the paper as I was simply listing the holotype for reference.

2) I am looking into this issue in more detail based on your comments and seeing what the options are for modification, if needed.

3) I only mention the clade Jeholosauridae in passing to say that this analysis does not recover a clade composed on Jeholosaurus, Changchunsaurus, and Haya, which were the original taxonomic contents of Jeholosauridae. I do not say that the clade Jeholosauridae is invalid or should not be used. In fact, I never mention Jeholosauridae again in the paper. The posted comment is correct that Jeholosauridae would now apply to the small clade of Jeholosaurus + Yueosaurus. I did not deny that in the paper, I just didn't label Jeholosauridae on any of the figures or discuss its current taxonomic contents based on this study.

Thank you for your input, and I will continue looking into the third issue you raised and post a response at a later time.

Clint Boyd

waiting for moderation