Saturday, April 28, 2018

Lori paper submitted

Hi all.  With that juicy tagline, I'd like to restart regular blog posts here.  It took almost seven years to complete after I joined the Lori team (5-13-2011), but we submitted the manuscript a couple weeks ago and now it's in review.  I'd love to say more, but it's probably more professional to hold back until publication.  But man, did I get some interesting results.

In theropod news, Wang et al. (2018) published a new specimen of Iteravis, and agree with me that the genus is synonymous with Gansus zheni, but missed the whole ZooBank issue that gives zheni precedence over huchzermeyeri.  Does zheni clade with Gansus in the Lori analysis?  You gotta wait to see, though it is somewhat surprisingly the best basal Passer < - Enantiornis clade analysis yet, as it incorporates all of the Clarke bird characters and every Mesozoic taxon known from more than one element (except Gallornis... *cough*).

Also, Elzanowski et al. (2018) did an amazing job redescribing the skull of Confuciusornis, interpreting the supposed maxillary fenestra as a nasolacrimal foramen ('fl' in figure below).  Mayr is a coauthor, and his expertise with extant birds and crushed Messel specimens clearly helped, as the cranial reconstruction makes so much sense when you compare other confuciusornithiform skulls.  It's probably the most realistic Mesozoic bird skull drawing I've seen.  One frustrating consequence of their description and 2017 paper on temporal fenestrae in modern birds is that fusion in the absence of developmental data makes it difficult to impossible to homologize features with ancestral theropod elements and processes.  So we can't really say anything about the quadratojugal in Confuciusornis for instance.  With things like this and the Rauhut et al. (2018) Archaeopteryx paper describing a prefrontal in that genus, I wonder how much 'standard knowledge' of anatomy in a given genus would be exposed as uncertain to false given enough scrutiny by other experts.

Cranial reconstruction of Confuciusornis sanctus in lateral view (A) with mandible in medial view (B) after Elzanowski et al. (2018).

Finally, a description of the Citipati Big Auntie specimen IGM 100/1004 was just published this week (Norell et al., 2018).  It's so similar in completeness and preservation to Big Mamma specimen IGM 100/978 that I thought the details on Conchoraptor and the Citipati holotype were most interesting, and am really looking forward to the AMNH papers on those specimens.  The Oviraptor info is also good to have in the literature, but isn't new to me since I saw it in 2009.  Well, the apparent baby oviraptorid hindlimb associated with the specimen is, but from my review of photos I took and those Senter took of a cast of the holotype before the manual elements were removed, I don't see where the juvenile tibia and metatarsals are in the holotype.

Dorsal vertebrae of Oviraptor philoceratops holotype AMNH 6517 (anterior to left) with proximal ribs, scapula in lower right.  Courtesy of the AMNH.

Let's try to make this blog a weekly thing again, if only in commentary.

References- Elzanowski and Mayr, 2017. Multiple origins of secondary temporal fenestrae and orbitozygomatic junctions in birds. Journal of Zoological Systematics and Evolutionary Research. 56(2), 248-269.

Elzanowski, Peters and Mayr, 2018. Cranial morphology of the Early Cretaceous bird Confuciusornis. Journal of Vertebrate Paleontology. e1439832.

Norell, Balanoff, Barta a nd Erickson, 2018. A second specimen of Citipati osmolskae associated with a nest of eggs from Ukhaa Tolgod, Omnogov Aimag, Mongolia. American Museum Novitates. 3899, 1-44.

Rauhut, Foth and Tischlinger, 2018. The oldest Archaeopteryx (Theropoda: Avialiae): A new specimen from the Kimmeridgian/Tithonian boundary of Schamhaupten, Bavaria. PeerJ. 6:e4191.

Wang, Huang, Hu, Liu, Peteya and Clarke, 2018. The earliest evidence for a supraorbital salt gland in dinosaurs in new Early Cretaceous ornithurines. Scientific Reports. 8:3969.