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Actinopteria: LBP4_21
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Actinopteria sp.?
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The bivalve Actinopteria was described from the Baton River deposits by both Shirley (1938) and Fleming (1957), and from the Reefton deposits by Bradshaw and Hegan (1983). Subsequently, however, Bradshaw and Campbell reclassified these specimens to various forms of Cornellites, as part of the national biodiversity inventory. Shirley referred to its semicircular outline and slightly convex profile, with the straight hinge defining its diameter. The umbo is positioned in the middle of the hinge, and the wings are somewhat unequal (the posterior wing being larger than the anterior). It is ornamented by radial ribs and fine, concentric growth-lines.
The specimen shown here is in a poor state so identification is uncertain. I've provisionally ascribed it to the Actinopteria but it may belong amongst the Cornellites. Further analysis, and better specimens, are required for a more confident identification. |
Further Reading: Bradshaw, M.A. and Hegan, B.D. 1983 Stratigraphy and structure of the Devonian rocks of Inangahua Outlier, Reefton, New Zealand. New Zealand Journal of Geology and Geophysics 26 (4), 325-344. Fleming, C.A. 1957 Lower Devonian pelecypoda from Reefton, New Zealand. Transactions of the Roya Society of New Zealand 85 (1), 135-140. Shirley, J. 1938 The fauna of the Baton River beds (Devonian), New Zealand. Quarterly Journal of the Geological Society 94, 459-506. |