A new genus and species of enantiornithine bird from the Early Cretaceous of Brazil

Ismar De Souza Carvalho,Marcelo P Isasi,Francisco I Freitas,Federico L Agnolín,Fernando E Novas,José A Andrade

doi:10.1590/23174889201500020001

Abstract

<p>The fossil record of birds in Gondwana is almost restricted to the Late Cretaceous. Herein we describe a new fossil from the Araripe Basin, <italic>Cratoavis cearensis</italic> nov. gen et sp., composed of an articulated skeleton with feathers attached to the wings and surrounding the body. The present discovery considerably extends the temporal record of the Enantiornithes birds at South America to the Early Cretaceous. For the first time, an almost complete and articulated skeleton of an Early Cretaceous bird from South America is documented.</p>

Highlights

In South America, the Cretaceous avian record is composed of several taxa, including basal ornithothoracine birds, enantiornithes, and derived ornithurines, including Neornithes-like taxa (Walker 1981, Alvarenga & Bonaparte 1992, Chiappe 1993, 1996, Chiappe & Calvo 1994, Clarke & Chiappe 2001, Agnolin & Martinelli 2009, Agnolín 2010)
Three reports of Cretaceous birds are known for the entire country, including unpublished indeterminate enantiornithine birds from Presidente Prudente locality (Alvarenga & Nava 2005), and indeterminate birds from Jales locality (Azevedo et al 2007), both coming from the Adamantina Formation (Turonian-Santonian, Bauru Group)
All the available data comes from the Santana Formation, Crato Member

Summary

INTRODUCTION

In South America, the Cretaceous avian record is composed of several taxa, including basal ornithothoracine birds, enantiornithes, and derived ornithurines, including Neornithes-like taxa (Walker 1981, Alvarenga & Bonaparte 1992, Chiappe 1993, 1996, Chiappe & Calvo 1994, Clarke & Chiappe 2001, Agnolin & Martinelli 2009, Agnolín 2010). As pointed out by Walker & Dyke (2009), in spite of the anatomical distinctiveness and ecological variability, the phylogenetic relationships among euenantiornithine genera still remains in state of flux, and little phylogenetic resolution has been achieved, lacking consensus about their interrelationships (Chiappe & Walker 2002; Chiappe et al 2007; OConnor et al 2011a, 2011b, 2013) In this way, the position of Cratoavis nov. The transverse ligamental groove and the capital groove of the humerus are poorly defined, which differs from the deep and well-defined groove present in Eoenantiornis (Zhou et al 2005) and Otogornis (Zhou & Hou 2002), and other derived forms (e.g., Concornis, Halimornis, Martinavis, Elbretornis and Enantiornis; Sanz et al 1995, Chiappe et al 2002; Walker & Dyke 2009) On the basis of the comparisons made above, we conclude that Cratoavis nov. gen. represents a valid genus of Enantiornithes, and can be diagnosed on the basis of a unique combination of characters

CONCLUSIONS

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