Gansuidae

Gansuidae is an extinct family of euornithean birds known from the Early Cretaceous of China and possibly the Late Cretaceous of Mongolia.

Gansuids Temporal range: Cretaceous (Aptian–?Campanian) PreꞒ Ꞓ O S D C P T J K Pg N
Fossil specimen of Gansus zheni
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Clade:	Dinosauria
Clade:	Saurischia
Clade:	Theropoda
Clade:	Avialae
Clade:	Euornithes
Family:	†Gansuidae Hou & Liu, 1984
Type genus
Gansus Hou & Liu, 1984
Genera
†Changzuiornis †Gansus †Hollanda? †Iteravis †Khinganornis †Shuilingornis

History and taxonomy

The Gansuidae was originally established as a monotypic family by Hou & Liu in their 1984 description of their new genus Gansus from the Xiagou Formation. Their characterization for this clade included shorebirds with slender toes, a long digit IV, and a laterally compressed tarsometatarsus shorter than the third and fourth digits.^[1] A second Gansus species, G. zheni, was described in 2014 from the Jiufotang Formation.^[2]

The clade received little attention in the following years, with most analyses failing to recover a substantial clade of taxa besides Gansus spp. However, the 2024 description of the genus Shuilingornis—also from the Jiufotang Formation—shed light on the relationships of several euornithean birds, with several taxa clustering in a monophyletic clade. Besides Gansus (the type genus of the family) and Shuilingornis, the group likely also includes Changzuiornis (Jiufotang Fm.),^[3] Iteravis (Yixian Formation),^[4] and Khinganornis (Longjiang Formation).^[5] These five genera were found in Aptian-aged (Early Cretaceous) outcrops in China.^[6]

The genus Hollanda is known from a fragmentary skeleton described in 2010 from the Campanian-aged (Late Cretaceous) Barun Goyot Formation of Mongolia. Originally identified as an ornithuromorphan,^[7] later analyses recovered conflicting phylogenetic positions, suggesting possible affinities with Songlingornis^[8] or even the Enantiornithes.^[9]In their description of Shuilingornis, Wang et al. (2024) noted Hollanda as one of several "wildcard taxa". When included in their phylogenetic analyses, it was recovered as a late-diverging member of the Gansuidae, as the sister taxon to Changzuiornis. However, they cautioned that these particular results were tentative and should not be considered definitive without the discovery of additional fossil material.^[6]

Classification

Reconstructed skeleton of Shuilingornis

In their phylogenetic analyses, Wang et al. (2024) recovered the Gansuidae as a clade of euornithean birds as the sister taxon to the Ornithuromorpha. Their results are displayed in the cladogram below:^[6]

	†Enantiornithes Euornithes   †Cruralispennia   †Zhongjianornis     †Dingavis   †Yumenornis †Xinghaiornis   †Archaeorhynchus   †Schizooura     †Tianyuornis †Archaeornithura     †Parahongshanornis †Longicrusavis †Hongshanornis   †Yixianornis †Yanornis †Ambiortus   †Piscivoravis Gansuidae     †Iteravis †Gansus yumenensis   †Khinganornis   †Shuilingornis †Changzuiornis Ornithuromorpha

References

1. Hou, Lianhai; Liu, Zhicheng (1984-12-10). "A new fossil bird from Lower Cretaceous of Gansu and early evolution of birds" (PDF). Scientia Sinica, Series B. 27 (12): 1296–1303. doi:10.1360/yb1984-27-12-1296 (inactive 1 November 2024).{{cite journal}}: CS1 maint: DOI inactive as of November 2024 (link)
2. Liu, Di; Chiappe, Luis M.; Zhang, Yuguang; Bell, Alyssa; Meng, Qingjin; Ji, Qiang; Wang, Xuri (2014-11-14). "An advanced, new long-legged bird from the Early Cretaceous of the Jehol Group (northeastern China): insights into the temporal divergence of modern birds". Zootaxa. 3884 (3): 253–266. doi:10.11646/zootaxa.3884.3.4. ISSN 1175-5334. PMID 25543783.
3. Huang, J.; Wang, X.; Hu, Y.; Liu, J.; Peteya, J.A.; Clarke, J.A. (2016). "A new ornithurine from the Early Cretaceous of China sheds light on the evolution of early ecological and cranial diversity in birds". PeerJ. 4: e1765. doi:10.7717/peerj.1765. PMC 4806634. PMID 27019777.
4. Zhou, Shuang; O’Connor, Jingmai K.; Wang, Min (2014-12-01). "A new species from an ornithuromorph (Aves: Ornithothoraces) dominated locality of the Jehol Biota". Chinese Science Bulletin. 59 (36): 5366–5378. Bibcode:2014ChSBu..59.5366Z. doi:10.1007/s11434-014-0669-8. ISSN 1861-9541.
5. Wang, Xuri; Cau, Andrea; Kundrát, Martin; Chiappe, Luis M.; Ji, Qiang; Wang, Yang; Li, Tao; Wu, Wenhao (2020-02-28). "A new advanced ornithuromorph bird from Inner Mongolia documents the northernmost geographic distribution of the Jehol paleornithofauna in China". Historical Biology. 33 (9): 1705–1717. doi:10.1080/08912963.2020.1731805. ISSN 0891-2963. S2CID 213971956.
6. Wang, Xuri; Cau, Andrea; Wang, Yinuo; Kundrát, Martin; Zhang, Guili; Liu, Yichuan; Chiappe, Luis M. (2024-09-24). "A new gansuid bird (Avialae, Euornithes) from the Lower Cretaceous (Aptian) Jiufotang Formation of Jianchang, western Liaoning, China". Cretaceous Research. 166 (in press): 106014. doi:10.1016/j.cretres.2024.106014. ISSN 0195-6671.
7. Bell, Alyssa K.; Chiappe, Luis M.; Erickson, Gregory M.; Suzuki, Shigeru; Watabe, Mahito; Barsbold, Rinchen; Tsogtbaatar, K. (2010-02-01). "Description and ecologic analysis of Hollanda luceria, a Late Cretaceous bird from the Gobi Desert (Mongolia)". Cretaceous Research. 31 (1): 16–26. Bibcode:2010CrRes..31...16B. doi:10.1016/j.cretres.2009.09.001. ISSN 0195-6671.
8. O’Connor, J. K.; Zhang, Y.; Chiappe, L. M.; Meng, Q.; Quanguo, L.; Di, L. (2013). "A new enantiornithine from the Yixian Formation with the first recognized avian enamel specialization". Journal of Vertebrate Paleontology. 33 (1): 1–12. Bibcode:2013JVPal..33....1O. doi:10.1080/02724634.2012.719176. S2CID 85261944.
9. Hartman, Scott; Mortimer, Mickey; Wahl, William R.; Lomax, Dean R.; Lippincott, Jessica; Lovelace, David M. (2019-07-10). "A new paravian dinosaur from the Late Jurassic of North America supports a late acquisition of avian flight". PeerJ. 7: e7247. doi:10.7717/peerj.7247. ISSN 2167-8359. PMC 6626525. PMID 31333906.