Songlingornithidae Explained

Songlingornithidae is a family of basal euornithean dinosaurs from the Early Cretaceous of China. All known specimens come from the Jiufotang Formation and the Yixian Formation, dating to the early Barremian and Aptian ages, 125–120 million years ago.

The family Songlingornithidae was first named by Hou in 1997 to contain the type genus, Songlingornis.^[1] Clarke et al. (2006) was the first to find a close relationship between Songlingornis and the "yanornithids".^[2]

The name was originally coined to reflect a close relationship between the two supposedly similar (but poorly preserved) genera Songlingornis and Chaoyangia. However, subsequent studies found that Chaoyangia was probably not closely related to Songlingornis. Instead, Songlingornis was found to be closely related to another group which had been given the name Yanornithidae—the name Songlingornithidae, having been named first, took precedence.^[3] Some later studies have also placed the hongshanornithids in this group.^{[3] [4]} At least one study has found the Late Cretaceous Mongolian avialan Hollanda to be a member of the group as well.^[5]

Phylogeny

Below is a cladogram from Mayr (2017) showing the relationships between Songlingornithidae and other ornithuromorphs:^[6]

A 2020 study by Wang et al. failed to recover a monophyletic Songlingornithidae, instead finding Yanornis to form a clade with the newly described genera Abitusavis and Similiyanornis, for which the name Yanornithidae was used:^[7]

Notes and References

1. Hou, (1997). Mesozoic Birds of China. Taiwan Provincial Feng Huang Ku Bird Park. Taiwan: Nan Tou. 228 pp.
2. Clarke, Zhou and Zhang, (2006). "Insight into the evolution of avian flight from a new clade of Early Cretaceous ornithurines from China and the morphology of Yixianornis grabaui." Journal of Anatomy, 208: 287-308.
3. O'Connor, J.K. and Zhou Z. (2012). "A redescription of Chaoyangia beishanensis (Aves) and a comprehensive phylogeny of Mesozoic birds." Journal of Systematic Palaeontology, (advance online publication).
4. Zhou . S. . Zhou . Z. . O'Connor . J. . A new piscivorous ornithuromorph from the Jehol Biota . 10.1080/08912963.2013.819504 . Historical Biology . 1 . 2013 .
5. O’Connor . J. K. . Zhang . Y. . Chiappe . L. M. . Meng . Q. . Quanguo . L. . Di . L. . 10.1080/02724634.2012.719176 . A new enantiornithine from the Yixian Formation with the first recognized avian enamel specialization . Journal of Vertebrate Paleontology . 33 . 1 . 2013 .
6. Mayr . G. . Pectoral girdle morphology of Mesozoic birds and the evolution of the avian supracoracoideus muscle . Journal of Ornithology . 2017 . 158 . 3 . 859–867 . 10.1007/s10336-017-1451-x.
7. Wang . M. . Li . Z. . Liu . Q. . Zhou . Z. . Two new Early Cretaceous ornithuromorph birds provide insights into the taxonomy and divergence of Yanornithidae (Aves: Ornithothoraces) . Journal of Systematic Palaeontology . 2020 . 18 . 21 . 1805–1827 . 10.1080/14772019.2020.1836050.