Reply to Li et al. “IsOculudentavisa bird or even archosaur?”

Abstract

We welcome any new interpretation or alternative hypothesis regarding the taxonomic affinity of the enigmatic Oculudentavis khaungraae. However, here we demonstrate that Li et al. have failed to provide conclusive evidence for the reidentification of HPG-15-3 as a squamate. We analyse this specimen in a matrix that includes a broad sample of diapsid reptiles and resolve support for this identification only when no avian taxa are included. Regardless of whether this peculiar skull belongs to a tiny bird or to a bizarre new group of lizards, the holotype of Oculudentavis khaungraae is a very interesting and unusual specimen, the discovery of which represents an important contribution to palaeontology. Its discovery documents a potential new case of convergent evolution in reptiles, while highlighting the importance of amber deposits for documenting taxa not recorded in sedimentary deposits.

The tiny Cretaceous stem-birdOculudentavisrevealed as a bizarre lizard

“…The interpretation of HPG-15-3 as a lizard rather than a bird, has already been made (Xing et al, 2020a); one metanalysis discussed its phylogenetic placement using an ad hoc revision of diagnostic features of diapsid clades, but without testing the position of Oculodentavis in phylogenetic analysis (Li et al, 2020). In response, the original authors added Oculudentavis to a amniote data set (Pritchard and Nesbitt, 2017) and recovered Oculodentavis as well nested among a group of Enanthiornithes birds (O'Connor et al, 2020), arguing that placement of this taxon with squamates only occurs if all avian taxa are removed. Herein, the phylogenetic allocation of Oculudentavis is tested in rigorous phylogenetic analyses using data derived from the holotype of O. khaungraae and additional data from the new specimen (GRS-Ref-28627).…”

Unusual morphology in the mid-Cretaceous lizard Oculudentavis

“…3 In a subsequent version of the paper, their hypothesis was tested and confirmed using an amniote data matrix 3 but with very limited sampling of squamates. In response to the first critique, 3 the original authors added Oculudentavis to an amniote dataset 4 and recovered Oculudentavis as well nested among a group of enantiornithine birds, 5 arguing that placement of this taxon with squamates only occurs if all avian taxa are removed. Herein, the phylogenetic allocation of Oculudentavis is tested in rigorous phylogenetic analyses using data derived from the holotype of O. khaungraae (HPG- and additional data from the new specimen (GRS-Ref-28627).…”