Lecho Formation

Saltasaurus (which means "lizard from Salta") is a genus of saltasaurid dinosaur of the Late Cretaceous period of Argentina. Small among sauropods, though still heavy by the standards of modern creatures, Saltasaurus was characterized by a short neck and stubby limbs. It was the first genus of sauropod known to possess armour of bony plates embedded in its skin. Such small bony plates, called osteoderms, have since been found on other titanosaurians.

Noasaurus ("Northwestern Argentina lizard") is a genus of ceratosaurian theropod dinosaur from the Maastrichtian (Late Cretaceous) of Argentina. The type and only species is N. leali. The fragmentary holotype specimen of Noasaurus, PVL 4061, consisting of a few cranial and postcranial bones, was discovered from strata from the Lecho Formation of Southern Salta in 1975 by a team led by José Fernando Bonaparte. When described by Bonaparte and in PhD student Jaime Powell in 1980, it was believed to be a coelurosaur theropod and assigned to a family of its own; this family, Noasauridae, still exis

Enantiornis is a genus of Enantiornithes. The type and only currently accepted species E. leali is from the Late Cretaceous Lecho Formation at El Brete, Argentina. It was described from specimen PVL-4035, a coracoid, proximal scapula and proximal humerus found close to each other and suspected to represent the left shoulder of a single individual.

Soroavisaurus is an extinct genus of enantiornithine birds that lived in South America during the Late Cretaceous period, about 71–69 million years ago. The only known species, Soroavisaurus australis, was named in 1993; the generic name means "sister to Avisaurus" (another enantiornithine believed to be its relative) while the specific name means "southern". All specimens confidently assigned to this species are fossilised leg bones collected from the Lecho Formation of El Brete, a locality in the province of Salta, Argentina. Some authors have proposed that either Enantiornis or Martinavis,

Yungavolucris is a genus of enantiornitheans. It contains the single species Yungavolucris brevipedalis, which lived in the Late Cretaceous (Maastrichtian, c.70.6 – 66 mya). The fossil bones were found in the Lecho Formation at estancia El Brete, Argentina."Yungavolucris brevipedalis" means "Short-footed Yungas bird". The generic name, Yungavolucris is after the Yungas region + the Latin volucris, which translates to "bird" (literally "flyer"). The specific name brevipedalis is from the Latin brevis, which means "short", + pedalis, from the Latin pes, meaning "foot".

Lectavis is a genus of enantiornithine avialan. Their fossil bones have been recovered from the Late Cretaceous (Maastrichtian, c. 70.6 – 66 mya) Lecho Formation at estancia El Brete, Argentina. The genus contains a single species, Lectavis bretincola.

Martinavis is a genus of enantiornithine birds which existed in what is now southern France, North America and Salta Province, Argentina during the late Cretaceous period. It was named by Cyril A. Walker, Eric Buffetaut and Gareth J. Dyke in 2007, and the type species is Martinavis cruzyensis.