Data from: Organic-walled microfossils from the Kistedalen Formation, Norway: acritarch chronostratigraphy of the Baltic Miaolingian and evolutionary trends of placoid acritarchs

<p>New acritarch data from the Kistedalen Formation based on two sections with continuous exposure allow to establish the most detailed Miaolingian acritarch biozonation in Baltica to date. Six interval zones previously established in Gondwana, the <em>Eliasum llaniscum, Cristallinium cambriense, Adara alea, Timofeevia lancarae, Cristallinium dubium</em> and <em>Vulcanisphaera turbata</em> zones, are identified, and their correlations within the Acado-Baltic Province examined. The diagnoses of <em>Retisphaeridium, Cristallinium, Retisphaeridium dichamerum, Retisphaeridium lechistanium, Cristallinium dubium</em> and <em>Cristallinium cambriense </em>are emended and the new species <em>Retisphaeridium rugulatum</em> sp. nov. and <em>Retisphaeridium minimum</em> sp. nov. are described. The diagnosis of R<em>etisphaeridium ovillense </em>(Cramer &amp; Díez) Vanguestaine is emended and the species assigned to <em>Dictyotidium ovillense</em> comb. nov. The main evolutionary changes of the placoid acritarchs during the Miaolingian are analysed. Comparison with previous acritarch data from the Kistedalen Formation suggest that different extraction methodologies may result in significant bias in the recovered fossil record.</p>