Monday, March 2, 2020

[PaleoOrnithology • 2020] Khinganornis hulunbuirensis • A New Advanced Ornithuromorph Bird from Inner Mongolia documents the northernmost Geographic Distribution of the Jehol Paleornithofauna in China


Khinganornis hulunbuirensis
Wang, Cau, Kundrát, Chiappe, Ji, Wang, Li & Wu, 2020

ABSTRACT
We describe a new taxon of advanced ornithuromorph bird, Khinganornis hulunbuirensis gen. et sp. nov., from the previously unreported Pigeon Hill locality of the Lower Cretaceous Longjiang Formation in the northern Greater Khingan Range area of Inner Mongolia, China. A cladistics analysis resolves K. hulunbuirensis as the sister group of a clade formed by Changzuiornis and Iteravis among ornithuromorphs. The osteohistological analysis indicates that K. hulunbuirensis is the first ornithuromorph that maintained an uninterrupted growth during a longer period characterised by slow deposition of low-vascularised and terminal avascular bone tissue. The relatively long hindlimbs and elongate pedal digits with long proximal phalanges suggest a wading and amphibious ecology for the new bird. The discovery of K. hulunbuirensis represents the first occurrence of Jehol birds in the Greater Khingan Range and documents the northernmost known geographic distribution of the celebrated avifauna in China. The new record implies more extended palaeogeographic range for the early diversification of Mesozoic birds on the eastern side of Laurasia.

KEYWORDS: Early Cretaceous, Longjiang formation, Jehol Biota, Ornithuromorpha, growth strategy

the holotype of Khinganornis hulunbuirensis gen. et sp. nov., SGM-AVE-2017001. A, slab-A; B, slab-B.
Abbreviations: ce, cervical vertebrae; co, coracoid; cv, caudal vertebrae; f, femur; fu, furcula; h, humerus; il, ilium; is, ischium; lr, left radius; lu, left ulna; ma, manus; pd, pedal digits; pu, pubis; rr, right radius; ru, right ulna; s, scapula; sk, skull; st, sternum; t, tibiotarsus; tm, tarsometatarsus. 
Scale bar = 2 cm.

Systematic palaeontology 
Class: Aves Linnaeus, 1758 
Pygostylia Chiappe, 2002 
Ornithothoraces Chiappe, 1995 
Ornithuromorpha Chiappe, 2002 

Genus: Khinganornis gen. nov.
 Type species: Khinganornis hulunbuirensis sp. nov. 

Derivation of name: The genus name is derived from the Greater Khingan Range in northeastern China, referring to the first fossil bird uncovered from the Greater Khingan Range at the time of publication. 

Khinganornis hulunbuirensis sp. nov.

Derivation of name: The species name refers to the fossil site located in Hulunbuir City.


Xuri Wang, Andrea Cau, Martin Kundrát, Luis M. Chiappe, Qiang Ji, Yang Wang, Tao Li and Wenhao Wu. 2020. A New Advanced Ornithuromorph Bird from Inner Mongolia documents the northernmost Geographic Distribution of the Jehol Paleornithofauna in China. Historical Biology: An International Journal of PaleobiologyDOI: 10.1080/08912963.2020.1731805