Large euenantiornithine birds from the Cretaceous of southern France, North America and Argentina

Abstract

We review historical approaches to the systematics of Enantiornithes, the dominant birds of the second half of the Mesozoic, and describe the forelimb remains of a new Cretaceous euenantiornithine. This taxon is known on the basis of fossil specimens collected from southern France, Argentina and the United States; such a wide geographical distribution is uncharacteristic for Enantiornithes as most taxa are known from single localities. Fossils from the Massecaps locality close to the village of Cruzy (Hérault, southern France), in combination with elements from New Mexico (USA) and from the Argentine locality of El Brete (Salta Province) testify to the global distribution of large flighted euenantiornithine birds in the Late Cretaceous. We discuss the systematics and taxonomy of additional isolated bones of Enantiornithes that were collected from the Argentine El Brete locality in the 1970s; the presence of these flying birds in Cretaceous rocks on both sides of the equator, in both northern and southern hemispheres, further demonstrates the ubiquity of this avian lineage by the latter stages of the Mesozoic.

A drowned Mesozoic bird breeding colony from the Late Cretaceous of Transylvania

“…Strong flight has been suggested for some larger enantiornithines, like Enantiornis (cf. the Od bones) and Martinavis, known from fossil specimens widely separated geographically (Walker et al 2007). The presence of possibly synchronous, colonial breeding in turn implies that the Od enantiornithines were taking advantage of seasonally abundant but localised food resources.…”

Additional non-avian theropod and bird remains from the early Late Cretaceous (Santonian) of Hungary and a review of the European abelisauroid record

“…Only three taxa, a giant ground bird Gargantuavis philoinos Buffetaut and Le Loeuff, 1998 and two enantiornithine Martinavis cruzyensis Walker, Buffetaut and Dyke, 2007 and Bauxitornis mindszentyae Dyke and Ősi, 2010 have been identified at species level. Most of the additional, isolated bird bones were mainly referred to enantiornithine (Buffetaut 1998;Buffetaut et al 2000, Dyke et al 2008, Ősi 2008 and ornithurine (Dyke et al 2002, Dyke et al 2008, Wang et al 2010 birds.…”

The first definitive record of a fossil bird from the Upper Cretaceous (Maastrichtian) of the Haţeg Basin, Romania

“…Buffetaut (1998) then presented the first European records from the Late Cretaceous, a coracoid and femur from the village of Cruzy in the south of France. Additional specimens, also from the south of France, of similar age including some very large possible enantiornithines have now been reported (Buffetaut et al 2000;Walker et al 2007). Elsewhere in Europe, fragmentary specimens from the Santonian have been described from Hungary (Ősi 2008;Dyke and Ősi 2010) and from the Maastrichtian type−section at Maastricht, the Netherlands (Dyke et al , 2008.…”

“…Our description here is based on the more complete humerus (NVEN 1) which is long (53 mm), robust, and slightly twisted so that its proximal and distal ends are expanded in different planes. This bone is longer than the majority of Early Cretaceous enan− tiornithines, but shorter than Pengornis (64.3 mm), the largest Early Cretaceous taxon from China, Concornis (68.1 mm) from the Early Cretaceous of Spain, and Martinavis (90-110 mm) from the Late Cretaceous of southern France, America and Ar− gentina (Walker et al 2007). The shape of the Romanian humerus is also not as sigmoid as is in Cathayornis, Concornis, and Eoenantiornis (Fig.…”

“…Enantiornithine birds are now known to be the most diverse of the lineages of avians from the Cretaceous (Walker et al 2007). These taxa were first recognized by Walker (1981), who noted a series of novel morphologies in a collection of Late Cretaceous bones from the Argentine locality of El Brete (Walker and Dyke 2010).…”