Acrocanthosaurus: the high‑spined theropod of the Lower Cretaceous Acrocanthosaurus Acrocanthosaurus was a large high‑spined theropod from Lower Cretaceous North America, notable for tall neural spines, robust forelimbs, and its likely placement among the carcharo…
Alectrosaurus — a Late Cretaceous tyrannosauroid from Asia Alectrosaurus Alectrosaurus was a lightly built, fast-running tyrannosauroid dinosaur from Late Cretaceous Mongolia and China. Known from partial remains, its exact relationships and lifestyle r…
Allosauroidae: the allosauroid theropods Allosauroidae Allosauroidae were a diverse clade of large theropod dinosaurs known from the Middle Jurassic to the Late Cretaceous. This article outlines their traits, history, notable genera, a…
Alvarezsaurus: a small Late Cretaceous theropod from Argentina Alvarezsaurus Alvarezsaurus is a small bipedal theropod from Upper Cretaceous Argentina (≈86–83 Ma). A basal alvarezsaur with cursorial hindlimbs, it helps document the transition to the short-a…
Aurornis xui: basal bird-like theropod from Late Jurassic–Early Cretaceous China Aurornis Aurornis xui, a basal bird-like theropod from Late Jurassic–Early Cretaceous China, known from a near-complete fossil; its age and primitive features illuminate early avian evoluti…
Bicentenaria: a small coelurosaurian theropod from Late Cretaceous Argentina Bicentenaria Bicentenaria is a genus of small carnivorous coelurosaurian theropods from Argentina, known from early Late Cretaceous (~90 Ma) deposits. The type species is Bicentenaria argentina…
