''Dromiceiomimus'' is a genus of ornithomimid

theropod Theropoda (; from ancient Greek , (''therion'') "wild beast"; , (''pous, podos'') "foot"">wiktionary:ποδός"> (''pous, podos'') "foot" is one of the three major groups (clades) of dinosaurs, alongside Ornithischia and Sauropodom ...

from the Late Cretaceous (early

Maastrichtian The Maastrichtian ( ) is, in the International Commission on Stratigraphy (ICS) geologic timescale, the latest age (geology), age (uppermost stage (stratigraphy), stage) of the Late Cretaceous epoch (geology), Epoch or Upper Cretaceous series (s ...

) of

Alberta Alberta is a Provinces and territories of Canada, province in Canada. It is a part of Western Canada and is one of the three Canadian Prairies, prairie provinces. Alberta is bordered by British Columbia to its west, Saskatchewan to its east, t ...

, Canada. The type species, ''D. brevitertius'', is considered a synonym of ''

Ornithomimus edmontonicus ''Ornithomimus'' (; "bird mimic") is a genus of Ornithomimosauria, ornithomimid Theropoda, theropod dinosaurs from the Campanian and Maastrichtian ages of Late Cretaceous Laramidia, Western North America. ''Ornithomimus'' was a swift, bipedal din ...

'' by some authors, while others consider it a distinct and valid taxon. It was a small ornithomimid that weighed about .

Taxonomy

The type species, ''D. brevitertius'' was originally described as a species of '' Struthiomimus'' by William Parks in 1926 on the basis of a partial postcranium, ROM 797, from the Horseshoe Canyon Formation of Alberta, Canada. In his review of Canadian ornithomimids, Dale Russell made ''S. brevitertius'' the type species of a new genus, ''Dromiceiomimus'', meaning "

emu The emu (; ''Dromaius novaehollandiae'') is a species of flightless bird endemism, endemic to Australia, where it is the Tallest extant birds, tallest native bird. It is the only extant taxon, extant member of the genus ''Dromaius'' and the ...

mimic" from the old generic name for the emu, ''Dromiceius''. Russell also synonymized ''Struthiomimus ingens'' with ''Dromiceimimus brevitertius''. He renamed ''Ornithomimus samueli'' into a second ''Dromiceiomimus'' species: ''Dromiceiomimus samueli''. ''Dromiceiomimus'' was distinguished from ''

'' on the basis of the following characters: humerus shorter than scapula; ulna ~70% of femoral length; preacetabular process, tibia, metatarsus and pedal digit III longer compared to femur. In a 1981 publication, however, Nicholls and Russell cast doubt on the validity of ''Dromiceiomimus'' and though keeping it distinct from ''Ornithomimus'' argued that the limb proportions might be insufficient to distinguish ornithomimid taxa from each other. In the second edition of the Dinosauria, Makovicky et al. claimed that there is no statistical support for the distinction of ''Dromiceiomimus'' from ''Ornithomimus'', and synonymized it with ''Ornithomimus edmontonicus'' Sternberg 1933. However, a few authors continued to treat ''Dromiceiomimus'' as valid, and Longrich (2008, 2014) treated ROM 840 (holotype of ''Struthiomimus samueli'') as a distinct species of ornithomimid related to ''Ornithomimus''. In 2018, Ian McDonald and Philip John Currie rejected the conclusions by Makovicky and colleagues. They showed that the thighbone/shinbone ratio of specimen UALVP 16182, found in 1967 by Richard Fox and referred to ''Dromiceiomimus'', differed significantly from that of ''Ornithomimus edmontonicus''. They also pointed out that if both species were to be considered synonymous nevertheless, the specific name ''brevitertius'' would have priority.Ian Macdonald & Philip J. Currie, 2018, "Description of a partial ''Dromiceiomimus'' (Dinosauria: Theropoda) skeleton with comments on the validity of the genus", ''Canadian Journal of Earth Sciences''

References

{{Taxonbar, from=Q1144395 Ornithomimidae Dinosaur genera Maastrichtian dinosaurs Horseshoe Canyon Formation Taxa named by Dale Russell Fossil taxa described in 1972 Dinosaurs of Canada