Bradycneme

Bradycneme
Temporal range: Maastrichtian, 70–66 Ma
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B. draculae speculatively restored as an alvarezsaurid
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Clade: Saurischia
Clade: Theropoda
Family: †Alvarezsauridae
Genus: †Bradycneme
Harrison & Walker, 1975
Species:
†B. draculae
Binomial name
†Bradycneme draculae
Harrison & Walker, 1975

Bradycneme (meaning "ponderous leg") is a genus of theropod dinosaur from the Maastrichtian-age Upper Cretaceous Sânpetru Formation of the Hațeg Basin, Transylvania, Romania. The genus contains a single species, Bradycneme draculae, known only from a partial right lower leg (specimen BMNH A1588), which its original describers believed came from a giant owl.

History

In 1975, Harrison and Walker described two "bradycnemids" from Romania: B. draculae and Heptasteornis andrewsi. These specimens had initially been assigned to the supposed pelecaniform bird Elopteryx nopcsai. The generic name, Bradycneme, comes from the Ancient Greek bradys (βραδύς), meaning "slow, ponderous" and kneme (κνήμη), meaning "leg", as the holotype, BMNH A1588, a 37.8 millimetres (1.49 in) wide distal tibiotarsus found by Maud Eleanora Seeley, would be very stout if the animal had been an owl, with a body height of about 2 metres (6.6 ft).[1] The specific name, draculae, is derived from Romanian dracul, meaning "the dragon," and refers to Dracula.[1]

Starting with Pierce Brodkorb, the specimens were soon compared to small theropod dinosaurs.[2] Bradycneme, Elopteryx and Heptasteornis have been synonymized, split, and reassessed numerous times since then in part because of the fragmentary nature of the remains; there exist three proximal femora and three distal tibiotarsi, which may belong to one, two, or three species.[3] Usually, at least one of them is considered to be a troodontid.

In the most recent assessments, Bradycneme and Heptasteornis were found to be the same and most likely basal members of the Tetanurae in one study,[4] but Darren Naish and Gareth J. Dyke did not follow the synonymy and found Heptasteornis to be an alvarezsaurid, while classifying Bradycneme as an indeterminate maniraptoran.[5] In a 2011 classification, Tom Holtz assigned Bradycneme to the Alvarezsauridae along with Heptasteornis.[6]

References

  1. ^ a b Harrison & Walker (1975)
  2. ^ Brodkorb (1978): pp.223-224
  3. ^ Paul (1988), Weishampel et al. (1991), Le Loeuff et al. (1992), Csiki & Grigorescu (1998), Naish & Dyke (2004)
  4. ^ Csiki & Grigorescu (1998)
  5. ^ Naish & Dyke (2004)
  6. ^ Holtz, Thomas R. Jr. (2011) Dinosaurs: The Most Complete, Up-to-Date Encyclopedia for Dinosaur Lovers of All Ages, Winter 2010 Appendix.

Bibliography

  • Brodkorb, Pierce (1978): Catalogue of fossil birds, Part 5 (Passeriformes). Bulletin of the Florida State Museum, Biological Sciences 23(3): 139–228.
  • Csiki, G. & Grigorescu, D. (1998): Small theropods from the Late Cretaceous of the Hateg Basin (western Romania) - an unexpected diversity at the top of the food chain. Oryctos 1: 87–104.
  • Harrison, Colin James Oliver & Walker, Cyril Alexander (1975): The Bradycnemidae, a new family of owls from the Upper Cretaceous of Romania. Palaeontology 18(3): 563–570. PDF fulltext
  • Le Loeuff, J.; Buffetaut, E.; Méchin, P. & Méchin-Salessy, A. (1992): The first record of dromaeosaurid dinosaurs (Saurischia, Theropoda) in the Maastrichtian of southern Europe: palaeobiogeographical implications. Bulletin de la Société géologique de la France 163(3): 337–343.
  • Naish, Darren & Dyke, Gareth J. (2004): Heptasteornis was no ornithomimid, troodontid, dromaeosaurid or owl: the first alvarezsaurid (Dinosauria: Theropoda) from Europe. Neues Jahrbuch für Geologie und Paläontologie - Monatshefte 7: 385–401.
  • Paul, Gregory S. (1988): Predatory Dinosaurs of the World. New York, Simon & Schuster. ISBN 0-671-61946-2
  • Weishampel, D. B.; Grigorescu, D. & Norman, D. B. (1991): The dinosaurs of Transylvania. National Geographic Research and Exploration 7(2): 196–215. PDF fulltext