Struthiosaurus

Struthiosaurus (Latin struthio = ostrich + Greek sauros = lizard) is one of the smallest known and most basal genera of nodosaurid dinosaurs, from the Late Cretaceous period (Campanian-Maastrichtian) of Austria, Romania and France in Europe.[1] It was protected by body armour. Although estimates of its length vary, it may have been as small as 2.2 metres (7.2 ft) long.

Taxonomy and Valid Species
Originally described in 1871 by Emanuel Bunzel,[3] after remains uncovered by Eduard Suess and Ferdinand Stoliczka in 1855 from the Gute Hoffnung coal mine at Muthmannsdorf near Wiener Neustadt in Austria. Many species have been referred to Struthiosaurus, most based on very fragmentary and nondiagnostic material. Three valid species are currently recognized by paleontologists: S. austriacus Bunzel, 1871, based on holotype PIWU 2349/6; S. transylvanicus Nopcsa, 1915, based on BMNH R4966, a skull and partial skeleton from Romania;[4] and S. languedocensis Garcia and Pereda-Suberbiola, 2003, based on UM2 OLV-D50 A–G CV, a partial skeleton found in 1998 in France.[5] Along with Hungarosaurus Ösi, 2005, Struthiosaurus is currently one of only two valid members of the Ankylosauria known from Europe.

Phylogeny
Struthiosaurus was originally by Bunzel considered a predator that he assigned to the new taxon Ornithocephala ("Bird Heads"). The generic name is a reference to the affinities with birds shown by traits in the skull. The first to understand it represented an armoured dinosaur was Nopcsa who in 1902 placed it in the Acanthopholididae.[9] He later corrected its name to Acanthopholidae.[10] Walter Coombs in 1978 stated it was a nodosaurid.[11]

Cladistic analysis of Struthiosaurus (Ösi, 2004) indicates that the taxon is a basal member of the Nodosauridae and suggests it may be one of the most basal ankylosaurs in the clade Ankylosauria.

Some workers (Vickaryous, Maryanska, and Weishampel 2004) consider the assignment of Struthiosaurus to the Nodosauridae to be provisional, pending further study and future discoveries