The brachiopod genus Dicoelosia is generally considered a typical deep-water taxon. New data suggest that some species of the genus may have invaded relatively shallow-water habitats during its geological history. However, there is scant evidence for its invasion of shallow-water environments after the terminal Ordovician mass extinction. Dicoelosia occurs in the shallower-water benthic shelly assemblages of the lower Niuchang Formation (upper Rhuddanian, Llandovery) of Meitan County, northern Guizhou Province, South China. Evidence of a move to shallow water includes its morphology and population structure, regional paleogeography, sedimentology, together with the abundance and diversity of its shallow-water associates. Following the biotic crisis, deep-water environments were barely habitable, and may have driven Dicoelosia into shallower-water niches. The taxon endured the less suitable shallow-water environments until the deep-water benthic zones ameliorated after the recovery, implying a shallow-water refugium existed after the biotic crisis. A new species Dicoelosia cathaysiensis is erected herein. There is only one record of this genus in South China and this unique occurrence may reflect the distinctive paleobiogeography and environments of this region.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.
Vol. 87 • No. 2