In the March 2005 Science magazine announced material, after re-hydrating, that resembled soft tissue was discovered inside a Tyrannosaurus rex leg bone from the Hell Creek Formation in Montana, from about 68 million years ago.

When the fossilized bone was treated over several weeks to remove mineral content from the fossilized bone marrow cavity, they found evidence of intact structures such as blood vessels, bone matrix, and connective tissue. Scrutiny under microscope further revealed the putative dinosaur soft tissue had retained fine structures even at the cellular level. It has not been made clear of what this flexible material is actually composed, although many news reports immediately linked it with the movie, "Jurassic Park" and the interpretation of the artifact, as well as its relative importance of their discovery is still undecided.

Argentina-->Abelisaurus, Aeolosaurus, Alvarezsaurus, Amargasaurus, Amygdalodon, Andesaurus, Antarctosaurus, Argentinosaurus, Argyrosaurus, Campylodoniscus, Carnotaurus, Chubutisaurus, Clasmodosaurus, Coloradisaurus, Eoraptor, Frenguellisaurus, Gasparinisaura, Genyodectes, Giganotosaurus, Hadrosaurichnus, Herrerasaurus, Ischisaurus, Laplatasaurus, Loricosaurus, Megaraptor, Microsaurops, Mussaurus, Neuquensaurus, Noasaurus, Notoceratops, Opthalmosaurus, Patagosaurus, Piatnizkysaurus, Pisanosaurus, Pterodaustro, Quilmesaurus, Riojasaurus, Saltasaurus, Secernosaurus, Staurikosaurus, Triassolestes, Unenlagia, Unquillosaurus, Velocisaurus, Volkheimeria, Xenotarsosaurus

Bolivia -->Ankylosaur, and Triceratops track ways

Brazil --> Cearadactylus, Irritator, Santanaraptor, Staurikosaurus, Teyuwasu

Chile --> Antarctosaurus, Metriorhynchus(a crocodylian)

Patagonia, Argentina-->Abelisaurus, Carnotaurus, Coloradia, Gasparinisaura, Giganotosaurus, Notoceratops, Patagosaurus, Piatnitzkysaurus, Quilmesaurus, Unenlagia

South America --> Abelisaurus, Aeolosaurus, Alvarezsaurus, Amargasaurus, Amygdalodon, Andesaurus, Ankylosaur track ways, Antarctosaurus, Argentinosaurus, Argyrosaurus, Campylodoniscus, Carnotaurus, Cearadactylus, Chubutisaurus, Clasmodosaurus, Coloradisaurus, Cymbospondylus, Eoraptor, Frenguellisaurus, Eustreptospondylus, Gasparinisaura, Genyodectes, Giganotosaurus, Hadrosaurichnus, Herrerasaurus, Ichthyosaur, Iguanodon, Ischisaurus, Laplatasaurus. Lopicosaurus, Megaraptor, Mesosaurus, Mixosaurus, Mussaurus, Neuquensaurus, Noasaurus, Notoceratops, Opthalmosaurus, Patagosaurus, Piatnizkysaurus, Pisanosaurus, Pterodaustro, Quilmesaurus, Riojasaurus, Saltasaurus, Santanaraptor, Secernosaurus, Smilodon, Staurikosaurus, Triassolestes, Unenlagia, Unquillosaurus, Velocisaurus, Volkheimeria, Xenotarsosaurus

UTruguay -->Antarctosaurus, Argyrosaurus, Laplatasaurus