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Dracopelta (meaning “dragon shield”) is a monospecific genus of ankylosauria dinosaur from Portugal that lived during the Late Jurassic (uppermost lower Tithonian-upper Tithonian, 152.1-145.0 Ma) in what is now the Lourinhã Formation. The type and only species is Dracopelta zbyszewskii, which is represented by a partial skeleton including unpublished material.
The holotype was originally, and incorrectly, identified to be from the Kimmeridgian stage of Ribamar. However, Antunes and Mateus (2003) noted that at a locality named Ribamar, there are outcrops of Early Cretaceous that date to the Valanginian and Albian stages and deemed it as highly unlikely that the specimen was obtained from that locality. 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).
In 2019, a specimen of an ankylosaur consisting of a nearly complete skull, articulated dorsal vertebrae, proximal half of ribs, articulated anterior caudal vertebrae, mostly complete and articulated synsacrum, fragments of disarticulated and broken ribs, femora, partial with attached pelvic shield, humerus, partial scapulocoracoid, tendons mostly attached to vertebrae, and osteoderms from the Lourinhã Formation was reported. The specimen is currently being studied on to clarify if it represents an additional, more complete specimen, of Dracopelta or a new taxon.
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 tube 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, ornithopoda and possibly Scelidosaurus.
Suberbiola et al. (2005) noted that the manus of Dracopelta may have retained a primitive Phalanx bone, as in the nodosaurid Sauropelta and basal Scutellosaurus, while ankylosauridae and stegosauria 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.
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