Orienantius ritteri gen. et sp.. nov. (1 Viewer)

[Fred Ruhe]

Di Liu, L.M. Chiappe, Yuguang Zhang, F.J. Serrano & Qingjin Meng, 2018

Soft tissue preservation in two new enantiornithine specimens (Aves) from the Lower Cretaceous Huajiying Formation of Hebei Province, China

Cretaceous Research. in press. doi:10.1016/j.cretres.2018.10.017

Abstract: https://www.sciencedirect.com/science/article/pii/S0195667118301174?via=ihub


We describe two nearly complete enantiornithine skeletons from the Lower Cretaceous Huajiying Formation (ca. 130.7 Ma) of northern Hebei province, China. Many morphological features indicate that these specimens represent a new taxon, here named Orienantius ritteri gen. et sp.. nov. The new fossils preserve their plumage as well as rare information about their soft tissues, including the wing’s patagia. Multivariate analyses of their skeleton and flight feathers provide insight into the aerodynamic performance of these early enantiornithines, suggesting that these birds had evolved highly maneuverable, intermittent flap-gliding flight. Additionally, the presence in this new taxon of traits characteristic of younger enantiornithines and the broad phylogenetic spread of the clade during the Huajiying Formation corroborates previous claims that a significant episode of taxonomic differentiation took place prior to the earliest known phases of this clade’s evolutionary history.

Enjoy,

Fred

 

[Fred Ruhe]

Accepted manuscript:

https://www.sciencedirect.com/journal/cretaceous-research/articles-in-press

Systematic Paleontology

Aves Linnaeus, 1758
Pygostylia Chiappe, 2002
Ornithothoraces Chiappe, 1995
Enantiornithes Walker, 1981
Orienantius gen. nov.
Orienantius ritteri sp. nov.

Holotype. BMNHC Ph 1156a/b, a nearly complete and articulated skeleton preserved in two slabs (a/b) and surrounded by abundant feather impressions (Figs. 2, 3; Table 1). The lack of fusion among certain compound bones (i.e., carpometacarpus, tibiotarsus, tarsometatarsus) suggests that this specimen was not skeletally mature at the time of death, hence being considered as not fully grown.

Referred specimen. BMNHC Ph 1154a/b, also a nearly complete and articulated skeleton contained in two slabs (a/b), and preserving wing, body, and tail plumage (Fig. 4). BMNHC Ph 1154a/b is nearly identical to BMNHC Ph 1156a/b in every comparable aspect, including bone proportions and overall size. BMNHC Ph 1154a/b also exhibits the combination of characters diagnostic of Orienantius ritteri (see below), to the extent that preservation permits.

Geographic and Stratigraphic Provenance. Sichakou basin, Fengning county, northern Hebei Province, China (Fig. 1). Huajiying Formation, Lower Cretaceous, Hauterivian, ca. 130.7 Ma (Zhou, 2006; Jin et al., 2008; Pan et al., 2013).

Etymology. Orien from the Latin word for ‘dawn’ and enantius in reference to the clade Enantiornithes. The species name ritteri honors Polish-born physicist Johann Wilhelm Ritter whose discovery of ultraviolet light has allowed visualization of the soft tissues that are extraordinarily well-preserved in these new fossils.

Enjoy,

Fred

Orienantius ritteri gen. et sp. nov., BMNHC Ph 1156a/b, holotype, slab and counterslab