Lavocatavis is an extinct genus of prehistoric bird from the Eocene of Algeria. A fossilized femur was described from the Glib Zegdou Formation in 2011 and is the only known specimen of Lavocatavis. The species was designated L. africana.[1]

Lavocatavis
Temporal range: Eocene
52–46 Ma
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Genus: Lavocatavis
Mourer-Chauviré et al., 2011
Species:
L. africana
Binomial name
Lavocatavis africana
Mourer-Chauviré et al., 2011

Discovery and naming

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The holotype of Lavocatavis, UM HGL 51-55, consists of an almost complete right femur. It is reasonably well preserved in the middle, but fragmentary at both ends. It originates from layer HGL 51 of the Glib Zegdou Formation of Algeria. The generic epithet (meaning "Lavocat's bird") was named in honor of René Lavocat, the person who first reported the earth layer of the holotype.[1]

Paleobiogeography

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The oldest phorusrhacids are from South America and Antarctica, so if this genus were indeed a phorusrhacid, the ancestors of Lavocatavis might have migrated into Africa from the west. During the Eocene, the Atlantic Ocean separated South America from Africa by at least 1,000 kilometres (620 mi), ruling out a land migration. For a flightless terrestrial bird like Lavocatavis, the only means of entering Africa would have been through rafting on floating islands or island hopping. Currents traveled westward in the South Atlantic during the early Paleocene, making it unlikely that phorusrhacoids traveled on floating islands. The ancestors of Lavocatavis most likely traveled between very large islands that existed on what are now the submerged Rio Grande Rise and Walvis Ridge. However, it is also possible that the ancestors of Lavocatavis retained some of their flight ability and were able to travel between islands with more ease than flightless birds. If this was the case, Lavocatavis became flightless independently of other flightless phorusrhacoids, in a case of convergent evolution.[1]

Classification

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Along with Eleutherornis, it has been considered as a possible member of the family Phorusrhacidae outside the Americas,[2][3] but the taxonomic identity of both taxa is considered highly questionable.[4] However, Gerald Mayr suggested that Eleutherornis more closely resembles other cariamiforms Strigogyps and ?Dynamopterus anthracinus, while Lavocatavis is likely more related to a possible paleognath Eremopezus, questioning the taxonomic placement of both taxa as phorusrhacids.[5][6] Because the remains are too fragmentary, phylogenetic analysis cannot be conducted for both genera, and their relationships to phorusrhacids are only considered tentative.[4]

References

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  1. ^ a b c Cécile Mourer-Chauviré; Rodolphe Tabuce; M’hammed Mahboubi; Mohammed Adaci; Mustapha Bensalah (2011). "A phororhacoid bird from the Eocene of Africa". Naturwissenschaften. 98 (10): 815–823. Bibcode:2011NW.....98..815M. doi:10.1007/s00114-011-0829-5. PMID 21874523. S2CID 19805809.
  2. ^ Angst, D.; Buffetaut, E.; Lécuyer, C.; Amiot, R. (2013). ""Terror Birds" (Phorusrhacidae) from the Eocene of Europe Imply Trans-Tethys Dispersal". PLOS ONE. 8 (11): e80357. Bibcode:2013PLoSO...880357A. doi:10.1371/journal.pone.0080357. PMC 3842325. PMID 24312212.
  3. ^ Degrange, Federico J. (2020). "A revision of skull morphology in Phorusrhacidae (Aves, Cariamiformes)". Journal of Vertebrate Paleontology. 40 (6): e1848855. Bibcode:2020JVPal..40E8855D. doi:10.1080/02724634.2020.1848855. S2CID 234119602.
  4. ^ a b LaBarge, T. W.; Gardner, J. D.; Organ, C. L. (2024). "The evolution and ecology of gigantism in terror birds (Aves, Phorusrhacidae)". Proceedings of the Royal Society B: Biological Sciences. 291 (2021). 20240235. doi:10.1098/rspb.2024.0235. PMID 38654650. Supplementary Information
  5. ^ Mayr, G. (2017). "Cariamiforms and Diurnal Birds of Prey". Avian Evolution: The Fossil Record of Birds and its Paleobiological Significance. Chichester: Wiley-Blackwell. pp. 189–204. ISBN 978-1119020769.
  6. ^ Mayr, G. (2020). "An updated review of the middle Eocene avifauna from the Geiseltal (Germany), with comments on the unusual taphonomy of some bird remains". Geobios. 62: 45–59. doi:10.1016/j.geobios.2020.06.011.