Oculudentavis: three more things
July 26, 2020
For those following the saga of Oculudentavis (the beautiful tiny dinosaur preserved in amber that turned out to be a lizard), three more things.

Xing et al. 2020, Extended Data Fig. 2. Computed tomography scan of HPG-15-3 in palatal view, with the mandibles removed, and an isolated quadrate. a, Full palatal view. Dashed square box in a indicates the region enlarged in b [not shown]. bp, basipterygoid process; bs, basisphenoid plate; bsr, basisphenoid rostrum; ch, choana; dt, developing tooth; pt, pterygoid; pp, papillae; pmc, medial contact of the palatal processes of the premaxillae.
Second, David Marjanovic provided an excellent summary of the ICZN issues in a message on the Dinosaur Mailing List. (Summary: you can’t invalidate a name by retracting the paper in which it was erected.) David knows the details of the code as well as anyone, so his analysis is well worth reading.
Finally — and annoyingly, I can’t remember who put me on to this — an interesting Chinese-language article was published two days ago about the retraction [link] [Google translation]. (Apparently the word translated “oolong” should be “mistake”.) It contains a statement from Xing Lida, lead author of the original paper, on the reason for the retraction:
The reporter found that the key to retracting the manuscript was “research progress has been made on a new specimen with a more complete preservation of the same origin discovered by the author team.” The team realized that the skull of the new specimen was very similar to HPG-15-3, but the skeleton behind the head showed a typical squamosaurus form and should be classified as squamosaurus. This indicates that HPG-15-3 is likely to belong to the squamatosaurus, which is different from the initial conclusion.
But the article goes on to note that “there are many loopholes in this withdrawal statement”. It contains some illuminating analysis from Oliver Rauhut and Per Ahlberg, including this from Rauhut: “The main problem of the paper is that the author basically preconceived that the specimen was a bird and analyzed it under this premise (this is not necessarily intentional)“. And it claims:
As early as the evening of March 19, the corresponding author of the paper said in an interview with Caixin Mail, “She recognized the questioner’s conclusion-this is more likely to be a lizard than a bird.”
And this of course was nearly three months before the same author (Jingmai O’Connor) lead-authored the preprint reasserting the avian identity of Oculudentavis.
The more I read about all this, the stranger it seems.
Update (22 August 2020)
A new paper at Zoosystema (Dubois 2020) summarises the nomenclatural situation, citing SV-POW! in passing, and concludes that the name remains nomenclaturally valid despite the retraction of the paper in which is was named — quite rightly.
References
July 26, 2020 at 8:29 am
I assume that “Xu et al. 2000” in the caption meant “Xing et al. 2020”.
July 26, 2020 at 9:01 am
Thanks for catching that, Andrea. I see that I did the same thing in the previous post, too! Now fixed in both.
July 26, 2020 at 9:11 am
For a few minutes I hoped you did mention a 2000 paper describing a third specimen of the taxon…
July 26, 2020 at 9:19 am
Argh! Even when you reported it, I missed to 2000-for-2020 typo, blinded by the Xing-for-Xu typo! I admit I have impressed even myself here, by making two mistakes in a four-word citation (and the other two words were “et al“)! Thanks for point both out.
July 26, 2020 at 3:09 pm
That Chinese article is intriguing, this stands out:
“According to the time clues disclosed in the Caixin report, after the paper was confirmed to be accepted on January 22, 2020, the research team saw the new specimen and obtained important CT scan data of the new specimen before and after the paper was published on March 12 , And believe that the CT data of its posterior skull supports the hypothesis that the species is a lizard.”
July 28, 2020 at 11:52 pm
Incidentally, a far superior alternative to google translate is https://deepl.com (particularly for Chinese and Japanese). Although in this case it also gives “oolong”, if you click on that word, it lists alternatives like “orontosaur” and “urosaur”. It’s all Greek to me anyway (boom boom!), but if one of the alternatives sounds more plausible, click it, and deepl will then redo the sentence to fit. It’s an astonishing service.
July 28, 2020 at 11:53 pm
Incidentally, a far superior alternative to google translate is https://deepl.com (particularly for Chinese and Japanese). Although in this case it also gives “oolong”, if you click on that word, it lists alternatives like “orontosaur” and “urosaur”. It’s all Greek to me anyway (boom boom!), but if one of the alternatives sounds more plausible, click it, and deepl will then redo the sentence to fit. It’s an astonishing service.
July 29, 2020 at 10:09 am
Thanks, Thomas, that’s good to know!