Kentrosaurus

Kentrosaurus aethiopicus was a stegosaur from East Africa known for its dense array of defensive spikes. While its relative Stegosaurus featured large dorsal plates, Kentrosaurus had smaller plates over its neck and shoulders. These transitioned into long, sharp spikes that ran from the middle of its back to the end of its tail. Additionally, it possessed prominent spines that projected sideways from each shoulder. This configuration made it one of the most heavily guarded herbivores of the Late Jurassic.

This stegosaur was relatively small to mid-sized, measuring between 4.5 and 5.5 m and weighing 700 to 1,500 kg. It had the classic stegosaurian build with high hips and a low-slung head. Its small, narrow skull contained a beak and leaf-shaped teeth. The animal's hindlimbs were robust, while its forelimbs were comparatively short. Its unique shoulder spines, which projected from the scapulae, distinguished it from other members of Stegosauria.

Fossils were first collected during the German Tendaguru Expedition between 1909 and 1913. Edwin Hennig named the species in 1915 after the material was shipped to Berlin. Most of these specimens are kept at the Museum für Naturkunde, though British and Tanzanian expeditions have added to the collection since then.

In the Tendaguru Formation of Tanzania, Kentrosaurus shared a lagoonal-deltaic environment with the giant brachiosaurid Giraffatitan, the diplodocid Tornieria, and the theropods Elaphrosaurus and Veterupristisaurus. Its extensive armour likely served as protection against these predators. Biomechanical studies by Mallison (2011) suggest that Kentrosaurus could swing its tail in a broad horizontal arc with enough force to deter attackers. The shoulder spines would have made it difficult for a predator to strike from the side. Based on its teeth and skull structure, this dinosaur was a low-level browser that ate ferns, cycads, and conifers.

• MB.R.4800 (originally K.4) — composite mount, Museum für Naturkunde, Berlin.
• GPIT/RE/4801 — Tübingen specimen, University of Tübingen Palaeontological Collection.
• Multiple Tendaguru elements distributed across European museums.

Plate-and-spike arrangement — multiple reconstructions over the past century; current consensus (per Mallison 2010, 2011) places lateral shoulder spines on the scapula and alternating plates-and-spikes along the dorsum. Tail-spike combat — biomechanically supported. Phylogenetic position — well-resolved within Stegosauridae, close to Stegosaurus.

Kentrosaurus is less famous than Stegosaurus but features in Walking with Dinosaurs (1999) and many dinosaur reference works. The Berlin mount is one of the most-photographed stegosaur skeletons in the world.

• stegosauria
• stegosaurus
• tuojiangosaurus

• Hennig, E. (1915). Kentrosaurus aethiopicus, der Stegosauride des Tendaguru. Sitzungsberichte der Gesellschaft naturforschender Freunde zu Berlin, 1915, 219–247.
• Maidment, S. C. R., et al. (2008). Systematics and phylogeny of Stegosauria. Journal of Systematic Palaeontology, 6, 367–407.
• Mallison, H. (2010). The digital Plateosaurus II: an assessment of the range of motion of the limbs and vertebral column. Acta Palaeontologica Polonica, 55, 433–458.
• Mallison, H. (2011). Defense capabilities of Kentrosaurus aethiopicus Hennig, 1915. Palaeontologia Electronica, 14, 10A.