Lithornithidae Explained

Lithornithidae is an extinct, possibly paraphyletic[1] (but see below) group of early paleognath birds. They are known from fossils dating to the Upper Paleocene through the Middle Eocene of North America and Europe, with possible Late Cretaceous representatives.[1] [2] All are extinct today;[3] the youngest specimen is the currently unnamed SGPIMH MEV1 specimen from the mid-Eocene Messel Pit site.[4]

Lithornithids had long, slender, bills for probing. They closely resembled modern tinamous, aside from more developed wings. They possessed a rhynchokinetic skull with relatively unfused cranial bones, a weakly fused pygostyle and a splenial. The unguals were more curved than in tinamous and probably allowed better perching in trees.

The order Lithornithiformes was erected by Dr. Peter Houde in 1988. Initially, only three genera (Lithornis, Paracathartes, and Pseudocrypturus) and eight named species were included.[3] Promusophaga (Harrison & Walker, 1977) originally considered a stem-turaco, is considered synonymous with Lithornis vulturinus. Fissuravis may also belong to the clade,[5] and several unnamed remains are known.

Taxonomy

Lithornithiformes Houde, 1988[6] [7]

Several studies have shown conflicting status on the monophyly of the group. Some studies recover them as a paraphyletic assemblage leading to modern paleognaths,[1] but more recent examinations group them in a single, natural group basal to the rest of Palaeognathae.[8] Of issue is Paracathartes, which differs radically from other lithornithids and has been suggested to be more closely related to extant paleognaths,[9] though it is recently recovered as a derived lithornithid.[10]

Lithornis itself may be paraphyletic in relation to Paracathartes and Pseudocrypturus.[10]

Paleobiology

In a study about ratite endocasts, Lithornis ranks among the taxa with well developed olfactory lobes. This is consistent with a nocturnal, forest-dwelling lifestyle, though as much all volant birds it retains large optical lobes.[11]

Unlike modern tinamous, at least Lithornis has toe claws and reversed halluxes that allow for efficient perching.[1] Also unlike modern tinamous most lithornithids were capable flyers, with their wings and sterna comparable to those of storks and vultures[12] some even able to perform long distance migrations.[13] The exception is Paracathartes which was similar to modern tinamous and fowl in its sternum and wing proportions and likely was a burst flyer as well.[14]

Several egg fossils have been attributed to lithornithid birds.[1] Both Lithornis and Paracathartes have entire nests assigned to them.[15] Their eggshells are, perhaps unsurprisingly, noted as being "ratite-like".[16]

Studies on lithornithid feathers shows that some species had gloss similar to that of cassowaries.[17]

Lithornithids, much like modern paleognaths, ibises and shorebirds, had a vibrotactile bill tip organ, suggesting the development of this feature in the Cretaceous.[18]

External links

Notes and References

  1. https://books.google.com/books?id=P_TB72RBLLMC&dq=lithornithid+new+jersey&pg=PA27 Paleogene Fossil Birds
  2. http://escholarship.org/uc/item/6cm4v7h4 A lithornithid (Aves: Palaeognathae) from the Paleocene (Tiffanian) of southern California
  3. Houde . Peter W. . 1988 . Paleognathous Birds from the Early Tertiary of the Northern Hemisphere . Publications of the Nuttall Ornithological Club. 22 . Nuttall Ornithological Club . Cambridge Massachusetts, USA.
  4. Web site: First substantial Middle Eocene record of the Lithornithidae (Aves): A postcranial skeleton from Messel (Germany) . 11 June 2016 . https://web.archive.org/web/20110610063134/http://www.senckenberg.de/files/content/forschung/abteilung/terrzool/ornithologie/lithornithidae.pdf . 10 June 2011 . dead .
  5. Gerald Mayr, Paleogene Fossil Birds
  6. Mikko's Phylogeny Archive http://www.helsinki.fi/~mhaaramo/ Web site: Haaramo . Mikko . 2007 . Paleognathia – paleognathous modern birds . 30 December 2015.
  7. Web site: Taxonomic lists- Aves . Paleofile.com . 30 December 2015 . dead . https://web.archive.org/web/20160111195520/http://paleofile.com/ . 11 January 2016 .
  8. Nesbitt, Sterling J.; Clarke, Julia A., The anatomy and taxonomy of the exquisitely preserved Green River Formation (early Eocene) lithornithids (Aves) and the relationships of Lithornithidae. (Bulletin of the American Museum of Natural History, no. 406), 30 June 2016
  9. Houde, Peter W. (1988). "Paleognathous Birds from the Early Tertiary of the Northern Hemisphere". Publications of the Nuttall Ornithological Club (Cambridge, MA)
  10. Worthy . Trevor H. . Mitri . Miyess . Handley . Warren D. . Lee . Michael S. Y. . Anderson . Atholl . Atholl Anderson . Sand . Christophe . Evans . Alistair Robert . Osteology Supports a Stem-Galliform Affinity for the Giant Extinct Flightless Bird Sylviornis neocaledoniae (Sylviornithidae, Galloanseres) . PLOS ONE . 30 March 2016 . 11 . 3 . e0150871 . 10.1371/journal.pone.0150871 . 27027304 . 4814122 . 2016PLoSO..1150871W . free .
  11. Torres . Christopher R. . Clarke . Julia A. . Nocturnal giants: evolution of the sensory ecology in elephant birds and other palaeognaths inferred from digital brain reconstructions . Proceedings of the Royal Society B: Biological Sciences . 31 October 2018 . 285 . 1890 . 20181540 . 10.1098/rspb.2018.1540 . 30381378 . 6235046 . free .
  12. Houde, Peter W. (1988). "Paleognathous Birds from the Early Tertiary of the Northern Hemisphere". Publications of the Nuttall Ornithological Club (Cambridge, MA)
  13. Torres, Christopher R.; Norell, Mark A.; Clarke, Julia A. (2019). "Estimating Flight Style of Early Eocene Stem Palaeognath Bird Calciavis grandei(Lithornithidae)". The Anatomical Record. doi:10.1002/ar.24207. PMID 31313482.
  14. Houde, Peter W. (1988). "Paleognathous Birds from the Early Tertiary of the Northern Hemisphere". Publications of the Nuttall Ornithological Club (Cambridge, MA)
  15. Houde, Peter W. (1988). "Paleognathous Birds from the Early Tertiary of the Northern Hemisphere". Publications of the Nuttall Ornithological Club (Cambridge, MA) 22.
  16. Grellet-Tinner . Dyke . Gareth J. . Gerald . The eggshell of the Eocene bird Lithornis – Acta Palaeontologica Polonica . Acta Palaeontologica Polonica . 2005 . 50 . 4 . 831–835 .
  17. Eliason . Chad M. . Clarke . Julia A. . Cassowary gloss and a novel form of structural color in birds . Science Advances . 13 May 2020 . 6 . 20 . eaba0187 . 10.1126/sciadv.aba0187 . 32426504 . 7220335 . 2020SciA....6..187E .
  18. 10.1098/rspb.2020.2322. Cretaceous origins of the vibrotactile bill-tip organ in birds. 2020. Du Toit. C. J.. Chinsamy. A.. Cunningham. S. J.. Proceedings of the Royal Society B: Biological Sciences. 287. 1940. 33259758. 7739938.

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Lithornithidae".

Except where otherwise indicated, Everything.Explained.Today is © Copyright 2009-2024, A B Cryer, All Rights Reserved. Cookie policy.