Alamosaurus
Alamosaurus (; meaning "Ojo Alamo lizard") is a genus of titanosaurian sauropod dinosaurs, containing a single known species, Alamosaurus sanjuanensis, from the late Cretaceous Period of what is now southern North America. Isolated vertebrae and limb bones indicate that it reached sizes comparable to "Argentinosaurus" and "Puertasaurus", which would make it the largest dinosaur known from North America. Its fossils have been recovered from a variety of rock formations spanning the Maastrichtian age of the late Cretaceous period. Specimens of a juvenile "Alamosaurus sanjuanensis" have been recovered from only a few meters below the Cretaceous-Paleogene boundary in Texas, making it among the last surviving non-avian dinosaur species.
Dromaeosauridae
Dromaeosaurids were small to medium-sized dinosaurs, ranging from about in length (in the case of "Mahakala") to approaching or over (in "Utahraptor", "Dakotaraptor" and "Achillobator"). Some may have grown larger; undescribed specimens of "Utahraptor" in Brigham Young University collections belonged to individuals that may have reached up to long, though these await more detailed study. Large size appears to have evolved at least twice among dromaeosaurids; once among the dromaeosaurines "Utahraptor" and "Achillobator", and again among the unenlagiines ("Austroraptor", which measured long). A possible third lineage of giant dromaeosaurids is represented by isolated teeth found on the Isle of Wight, England. The teeth belong to an animal the size of the dromaeosaurine "Utahraptor", but they appear to belong to velociraptorines, judging by the shape of the teeth.