Dracopelta

In 1963 or, more likely, early 1964, a partial skeleton was discovered during road construction works between the village of Barril and Praia da Assenta. Pereda-Suberbiola et al. (2005) determined that the specimen was from a locality constrained to the uppermost lower Tithonian-upper Tithonian which shows characteristics consistent with what is recognized in the Assenta Member of the Lourinhã Formation, an observation agreed upon by Russo and Mateus (2021). The specimen is currently being studied on to clarify if it represents an additional, more complete specimen, of Dracopelta or a new taxon. == Description ==

Dracopelta has an estimated body length of 3 metres (9.9 feet) and a weight of 300 kilograms (600 lb). The holotype specimen represents an adult individual. Galton (1980) originally diagnosed Dracopelta based on the small flat osteoderms, small medial paired circular plated with raised centre and rims, long anterolateral plates, narrow nonprojecting overlapping dorsolateral plates and overlapping laterally projecting lateral plates in the thoracic region. Suberbiola et al. (2005) later diagnosed Dracopelta based on the presence of proximal phalanges II and III as long as wide and distinctive osteoderm morphology. The dorsal ribs are gently curved which indicates that the back was broad, much like that of other ankylosaurs, Dryosaurus and Camptosaurus, and the base is at about the same level as the postzygapophyses and prezygapophyses. The prezygapophyses are just above the dorsal margin of the neural canal and are about 80 mm above the ventral rim of the centrum. The ribs are correlated with the possession of transverse processes that are inclined slightly upwards, a feature that differentiates it from Dacentrurus, a stegosaur also from the Lourinhã Formation. The holotype preserves ossified tendons which is a feature seen in ankylosaurs, ornithopods and possibly Scelidosaurus. Suberbiola et al. (2005) noted that the manus of Dracopelta may have retained a primitive phalangeal formula, as in the nodosaurid Sauropelta and basal thyreophoran Scutellosaurus, while ankylosaurids and stegosaurs showed a reduced phalangeal formula. Suberbiola et al. suggested that derived ankylosaurids and stegosaurs convergently evolved a tridactyl pes, with the loss of digit I, while Liaoningosaurus pertained a tetradactyl manus and a tridactyl pes. The authors interpreted that Dracopelta may have had cursorial adaptations as the autopodial structure falls into the metapodial range of the basal thyreophorans Scutellosaurus and Scelidosaurus, which were probably subcursorial. The small size of Dracopelta is also consistent with the interpretation. == Classification ==

Galton (1980) originally assigned Dracopelta to Nodosauridae, based on the morphology of the osteoderms. Suberbiola et al. (2005) were unable to recognize any polacanthid or nodosaurid characteristics and considered Dracopelta as a valid taxon based on the presence of proximal phalanges II and III as long as wide and distinctive osteoderm morphology. == Paleoenvironment ==

The holotype specimen of Dracopelta was obtained from a layer from the Assenta Member of the Lourinhã Formation, which dates to the uppermost lower and upper Tithonian stage of the Late Jurassic. indeterminate turiasaurian sauropods, indeterminate crocodylomorphs, and an indeterminate ankylosaur, which may represent a second and more complete specimen of Dracopelta. == See also ==