Virtually everyone is familiar with the Stegosaurus and its kin which wielded a bunch of spikes at the end of its tail that could puncture a foe. Thanks to cartoonist Gary Larson that part even has an official name:
Most people are also familiar with Ankylosaurs and the heavy "club" at the end of their tail that could break a large predator's leg.
Recently researchers announced the discovery of a previously unknown dinosaur (a new genus of anklosaurian) with its own unique weapon on its tail. In this case a giant serrated blade that given its mass could rip and tear into an opponents flesh quite effectively.
The remains were uncovered on the southern tip of Chile that lived at the end of the Cretaceous and is represented by a semi-articulated nearly complete specimen including its skull and mandible (lower jaw).
The specimen is an adult and at a little over six feet long (1.8 meters) and 220 lbs. (100 kilos) is a rather small ankylosaur and yet only the tail is completely distinctive.
The abstract from the paper Bizarre tail weaponry in a transitional ankylosaur from subantarctic Chile can be read below:
Most people are also familiar with Ankylosaurs and the heavy "club" at the end of their tail that could break a large predator's leg.
Recently researchers announced the discovery of a previously unknown dinosaur (a new genus of anklosaurian) with its own unique weapon on its tail. In this case a giant serrated blade that given its mass could rip and tear into an opponents flesh quite effectively.
The remains were uncovered on the southern tip of Chile that lived at the end of the Cretaceous and is represented by a semi-articulated nearly complete specimen including its skull and mandible (lower jaw).
The specimen is an adult and at a little over six feet long (1.8 meters) and 220 lbs. (100 kilos) is a rather small ankylosaur and yet only the tail is completely distinctive.
The abstract from the paper Bizarre tail weaponry in a transitional ankylosaur from subantarctic Chile can be read below:
ABSTRACT:
Armoured dinosaurs are well known for their evolution of specialized tail weapons—paired tail spikes in stegosaurs and heavy tail clubs in advanced ankylosaurs1. Armoured dinosaurs from southern Gondwana are rare and enigmatic, but probably include the earliest branches of Ankylosauria2,3,4. Here we describe a mostly complete, semi-articulated skeleton of a small (approximately 2 m) armoured dinosaur from the late Cretaceous period of Magallanes in southernmost Chile, a region that is biogeographically related to West Antarctica5. Stegouros elengassen gen. et sp. nov. evolved a large tail weapon unlike any dinosaur: a flat, frond-like structure formed by seven pairs of laterally projecting osteoderms encasing the distal half of the tail. Stegouros shows ankylosaurian cranial characters, but a largely ancestral postcranial skeleton, with some stegosaur-like characters. Phylogenetic analyses placed Stegouros in Ankylosauria; specifically, it is related to Kunbarrasaurus from Australia6 and Antarctopelta from Antarctica7, forming a clade of Gondwanan ankylosaurs that split earliest from all other ankylosaurs. The large osteoderms and specialized tail vertebrae in Antarctopelta suggest that it had a tail weapon similar to Stegouros. We propose a new clade, the Parankylosauria, to include the first ancestor of Stegouros—but not Ankylosaurus—and all descendants of that ancestor.
Armoured dinosaurs are well known for their evolution of specialized tail weapons—paired tail spikes in stegosaurs and heavy tail clubs in advanced ankylosaurs1. Armoured dinosaurs from southern Gondwana are rare and enigmatic, but probably include the earliest branches of Ankylosauria2,3,4. Here we describe a mostly complete, semi-articulated skeleton of a small (approximately 2 m) armoured dinosaur from the late Cretaceous period of Magallanes in southernmost Chile, a region that is biogeographically related to West Antarctica5. Stegouros elengassen gen. et sp. nov. evolved a large tail weapon unlike any dinosaur: a flat, frond-like structure formed by seven pairs of laterally projecting osteoderms encasing the distal half of the tail. Stegouros shows ankylosaurian cranial characters, but a largely ancestral postcranial skeleton, with some stegosaur-like characters. Phylogenetic analyses placed Stegouros in Ankylosauria; specifically, it is related to Kunbarrasaurus from Australia6 and Antarctopelta from Antarctica7, forming a clade of Gondwanan ankylosaurs that split earliest from all other ankylosaurs. The large osteoderms and specialized tail vertebrae in Antarctopelta suggest that it had a tail weapon similar to Stegouros. We propose a new clade, the Parankylosauria, to include the first ancestor of Stegouros—but not Ankylosaurus—and all descendants of that ancestor.
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