Strophatrypa, a new genus of Brachiopoda (Atrypidae), from upper Silurian strata of the Alexander terrane, northeast Chichagof Island, Alaska

 

Authors: Boucot AJ, Blodgett RB, Rohr DM

Published in: Bulletin of Geosciences, volume 87, issue 2; pages: 261 - 267; Received 14 June 2011; Accepted in revised form 21 December 2011; Online 14 March 2012

Keywords: Brachiopoda, late Silurian, new genus, Alexander terrane, Southeast Alaska, U.S.A., palaeoecology, slope facies, palaeogeography,

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Abstract

The atrypid brachiopod Strophatrypa skaflestadi gen. et sp. nov. occurs in unnamed upper Silurian strata exposed near the town of Hoonah on northeast Chichagof Island, Southeast Alaska. The new genus represents the first strophic atrypoid with many characters otherwise similar to those of the Atrypidae. Although this genus is known from only a single bed at one Alaskan locality, its unique morphology is worth noting in anticipation that similar forms may be discovered elsewhere in the Alexander terrane, or especially somewhere in Siberia where other taxa restricted to the Silurian of the Alexander terrane are shared. This paper represents a further contribution to our limited knowledge of the Silurian brachiopods of the Alexander terrane of Southeast Alaska.

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