Vastanavidae

Summary

Vastanavidae is an extinct family of birds related to parrots and passerine birds. They are known from fossils from Eocene sites in India, Europe, and North America. The vastanavids resemble parrots and the extinct parrot relative Quercypsitta in their morphology, including the partially zygodactyl foot, in which two toes could face opposite the other two.

Vastanavidae
Temporal range: Eocene
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Clade: Australaves
Family: Vastanavidae
Mayr, 2010
Genera

Description edit

The Vastanavidae have a distinctive, parrot-like appearance. Notable anatomic features include a coracoid with a deep pit for the ball-and-socket joint of the shoulder, comparable to that of Quercypsitta. The humerus is built in a manner resembling birds of prey like hawks and falcons. The tarsometatarsus, the leg bone immediately above the foot, is short and stocky. Vastanavids had partially zygodactyl feet, as shown by skeletal features of the tarsometatarsus.[1] The phylogenetic affinities of vastanavids are not well known, nor their ecologies. The feet of Avolatavis and Eurofluvioviridavis may have been adapted for grasping.[2]

Distribution edit

Vastanavid birds have been found from three continents. Sites bearing vastanavid material include the Cambay Shale Formation in Gujarat province, India, where numerous bones of two species of Vastanavis have been found in a lignite mine.[3] Another vastanavid, Avolatavis, is known from the Green River Formation in the United States[4] as well as the London Clay of the United Kingdom.[5] The Geisel Valley of Germany has produced the vastanavid Eurofluvioviridavis.[2]

References edit

  1. ^ Mayr, Gerald (27 June 2015). "A reassessment of Eocene parrotlike fossils indicates a previously undetected radiation of zygodactyl stem group representatives of passerines (Passeriformes)". Zoologica Scripta. 44 (6): 587–602. doi:10.1111/zsc.12128. ISSN 0300-3256. S2CID 85599482.
  2. ^ a b Mayr, Gerald (2022). Paleogene fossil birds. Fascinating life sciences (2nd ed.). Cham: Springer. ISBN 978-3-030-87644-9.
  3. ^ Mayr, G.; Rana, R. S.; Rose, K. D.; Sahni, A.; Kumar, K.; Smith, T. (1 December 2013). "New specimens of the early Eocene bird Vastanavis and the interrelationships of stem group Psittaciformes". Paleontological Journal. 47 (11): 1308–1314. Bibcode:2013PalJ...47.1308M. doi:10.1134/S0031030113110105. ISSN 1555-6174. S2CID 89380736.
  4. ^ Ksepka, Daniel T.; Clarke, Julia A. (1 March 2012). "A new stem parrot from the Green River Formation and the complex evolution of the grasping foot in Pan-Psittaciformes". Journal of Vertebrate Paleontology. 32 (2): 395–406. Bibcode:2012JVPal..32..395K. doi:10.1080/02724634.2012.641704. ISSN 0272-4634. S2CID 85308803.
  5. ^ Mayr, Gerald; Kitchener, Andrew C. (28 February 2023). "The Vastanavidae and Messelasturidae (Aves) from the early Eocene London Clay of Walton-on-the-Naze (Essex, UK)". Neues Jahrbuch für Geologie und Paläontologie – Abhandlungen. 307 (2): 113–139. doi:10.1127/njgpa/2023/1119. S2CID 257598310.