Shangyang graciles gen. et sp. nov. (1 Viewer)

Min Wang & Zhounghe Zhou, 2019

A new enantiornithine (Aves: Ornithothoraces) with completely fused premaxillae from the Early Cretaceous of China

Journal of Systematic Palaeontology Latest Articles

Abstract: https://www.tandfonline.com/doi/full/10.1080/14772019.2018.1527403

We report a new small enantiornithine, Shangyang graciles gen. et sp. nov., based on a nearly complete and articulated skeleton from the Lower Cretaceous Jiufotang Formation of Liaoning Province, north-eastern China. Shangyang has premaxillae that are completely fused rostrally as well as along the frontal processes, a previously unrecognized condition in Early Cretaceous birds. As in three other enantiornithine taxa, Shangyang preserves a pair of craniolateral processes in the sternum. Phylogenetic analysis places Shangyang in a relatively derived position within Enantiornithes, suggesting that the craniolateral processes of the sternum evolved independently among some enantiornithine lineages from the condition seen in some basal ornithuromorphs. The craniolateral processes in modern birds provide the insertions of the M. sternocoracoideus that functions in the downstroke, which can also originate from the two cranialmost sternal ribs instead when these processes are absent. The altered origin of this muscle shows that diverse pectoral musculoskeletal modifications took place early in avian history.

http://zoobank.org/urn:lsid:zoobank.org:pub:20C69B6A-473B-4C6D-9672-F5B2CC2D8FE1


Keywords: birds, Enantiornithes, fusion, M. sternocoracoideus, Mesozoic, sternum

Enjoy,

Fred

Systematic palaeontology

Class Aves Linnaeus, 1758
Ornithothoraces Chiappe, 1995
Enantiornithes Walker, 1981
Genus Shangyang gen. nov.

Type species: Shangyang graciles sp. nov.

Derivation of name: ‘Shangyang’, referring to a Chinese mythological bird (‘rain bird’).

Shangyang graciles sp. nov.

Holotype: IVPP V25033, a nearly complete and articulated skeleton preserved on a single slab

Derivation of name: Derived from the Latin gracilis (slender), referring to the slender appendicular skeletons.

Occurrence and age: Mutouchengzi Township, Chaoyang City, Liaoning Province, China. Jiufotang Formation, Lower Cretaceous.

Fred

Some comments by David Marjanovic:

http://dml.cmnh.org/2019Jan/msg00051.html

"Shangyang graciles gen. et sp. nov.

graciles would be the masculine/feminine plural. Species names aren't allowed to be plural. I think this is automatically emended to the singular... but while the masculine/feminine singular would be good old gracilis, the neuter singular, gracile, occurs once in the paper (in the legend to fig. 2). So maybe graciles is a miscorrection for intended gracile? (Perhaps even done by the journal without informing the authors, as with Richardoestesia for Ricardoestesia.)

Being Chinese and thus genderless (even for ICZN purposes), the genus name doesn't help decide this question.

(The neuter plural, gracilia, does not occur in the paper.)"

Fred

Free pdf: https://www.tandfonline.com/doi/pdf/10.1080/14772019.2018.1527403?needAccess=true

Fred