Hypselornis
| Hypselornis Temporal range: Late Pliocene
| |
|---|---|
Scientific classification 
| |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Reptilia |
| Clade: | Archosauromorpha |
| Clade: | Archosauriformes |
| Order: | Crocodilia |
| Genus: | †Hypselornis Lydekker, 1929 |
| Type species | |
| †Hypselornis sivalensis Lydekker, 1929
| |
Hypselornis is a fossil bird from the Pliocene of India. Known from right toe digits and lower leg elements, this bird appears to have been a ratite similar to modern emus and cassowaries, in spite of its Asian distribution. A single species is known thus far, H. sivalensis.
Discovery and naming
The holotype of Hypselornis was found in the Siwalik Hills formation, dating to the Late Pliocene. It was first described in 1879 as Dromaius sivalensis, before a slightly younger revision allocated it to its own genus.[1]
Classification
Originally interpreted as an emu, a slightly younger revision shifted it to its own genus due to its geographical range as well as the presence of a hallux. It is nonetheless considered a close relative and classified within the Casuariidae.[2]
Paleogeographical implications
The presence of a casuariiform ratite in India originally puzzled researchers, who proposed a putative but unsatisfactory vicariant origin from India's Gondwanan past. In more recent years, ratites have been understood as having lost the ability to fly multiple times and likely having had a Laurasian origin, suggesting a more recent aerial dispersal across the various landmasses from northern lithornithid-like ancestors.[3][4]
Palaeobiology
Due to the presence of a hallux, as well as its forest habitat, Hypselornis is assumed to have been a cassowary or moa-like forest dweller.[citation needed]
References
- ^ Lowe, Percy Roycroft 1929. Some remarks on Hypselornis sivalensis Lydekker. Ibis. 71: (4) 571–576. (Journal Article)
- ^ Lowe, Percy Roycroft 1929. Some remarks on Hypselornis sivalensis Lydekker. Ibis. 71: (4) 571–576. (Journal Article)
- ^ Yonezawa, T.; Segawa, T.; Mori, H.; Campos, P. F.; Hongoh, Y.; Endo, H.; Akiyoshi, A.; Kohno, N.; Nishida, S.; Wu, J.; Jin, H.; Adachi, J.; Kishino, H.; Kurokawa, K.; Nogi, Y.; Tanabe, H.; Mukoyama, H.; Yoshida, K.; Rasoamiaramanana, A.; Yamagishi, S.; Hayashi, Y.; Yoshida, A.; Koike, H.; Akishinonomiya, F.; Willerslev, E.; Hasegawa, M. (2016-12-15). "Phylogenomics and Morphology of Extinct Paleognaths Reveal the Origin and Evolution of the Ratites". Current Biology. 27 (1): 68–77. doi:10.1016/j.cub.2016.10.029. PMID 27989673.
- ^ Phillips MJ, Gibb GC, Crimp EA, Penny D (January 2010). "Tinamous and moa flock together: mitochondrial genome sequence analysis reveals independent losses of flight among ratites". Systematic Biology. 59 (1): 90–107. doi:10.1093/sysbio/syp079. PMID 20525622.