Temporal range: Late Llandovery to ?Late Lochkovian
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, scales of a second species, B. robusta, 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.
- 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. 
- 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.
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