Birkenia

Birkenia Temporal range: Late Llandovery to ?Late Lochkovian
Birkenia elegans
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Anaspida
Genus:	Birkenia Traquair, 1899
Type species
Birkenia elegans Traquair, 1899
Species
B. elegans Traquair, 1899 B. robusta Blom, Märss et Miller, 2002

Birkenia is a genus of extinct anaspid fish from Middle Silurian strata of Northern Europe, and Middle Silurian to possibly Earliest Devonian strata of Arctic Canada.^[1] Intact fossil specimens of B. elegans suggest the living animal reached a length of up to 10.0 cm (3.9 in), and was an active swimmer. In addition to whole specimens and scale microfossils of B. elegans, which are found in Great Britain and Scandinavia,^[2] scales of a second species, B. robusta,^[1] are found in Late Silurian strata of Scandinavia and Estonia. The scales of B. robusta differ from those of B. elegans in that, as the specific epithet suggests, the scales of the former are more robustly proportioned than those of the latter.

References

1. Blom, Henning, T. Märss, and C. G. Miller. "Silurian and earliest Devonian birkeniid anaspids from the Northern Hemisphere." Earth and Environmental Science Transactions of the Royal Society of Edinburgh 92.03 (2001): 263-323.
2. Dineley, David L. & Metcalf, S. J. (1999). Fossil fishes of Great Britain (Volume 16 of Geological conservation review series). Joint Nature Conservation Committee. pp. 38, 46 (675). ISBN 9781861074706.