[2] The designated holotype for the genus and type species, Mapusaurus roseae, is an isolated right nasal (MCF-PVPH-108.1, Museo Carmen Funes, Paleontología de Vertebrados, Plaza Huincul, Neuquén).

[2][11][12] Coria and Currie speculated that this may represent a long term, possibly coincidental accumulation of carcasses (some sort of predator trap) and may provide clues about Mapusaurus behavior.

[2] Other known theropod bone beds and fossil graveyards include those of dromaeosaurids Deinonychus and Utahraptor,[13][14] those of Allosaurus from the Cleveland-Lloyd Dinosaur Quarry of Utah,[15] and those of tyrannosaurids Teratophoneus, Albertosaurus and Daspletosaurus.

[16] Paleontologist Rodolfo Coria, of the Museo Carmen Funes, contrary to his published article, repeated in a press-conference earlier suggestions that this congregation of fossil bones may indicate that Mapusaurus like Giganotosaurus also hunted in groups and worked together to take down large prey, such as the immense sauropod Argentinosaurus.

An ontogenetic study by Canale et al. (2014)[12] found that Mapusaurus displayed heterochrony, an evolutionary condition in which the animals may retain an ancestral characteristic during one stage of their life, but lose it as they develop.

A study of the El Zampal section of the formation found hornworts, liverworts, ferns, Selaginellales, possible Noeggerathiales, gymnosperms (including gnetophytes and conifers), and angiosperms (flowering plants), in addition to several pollen grains of unknown affinities.

[24] The Huincul Formation is among the richest Patagonian vertebrate associations, preserving fish including dipnoans and gar, chelid turtles, squamates, sphenodonts, neosuchian crocodilians, and a wide variety of dinosaurs.