Danian (Early Paleocene) echinoids from the Roca Formation, northern Patagonia, Argentina

作者：Martinez Sergio^*; del Rio Claudia J; Concheyro Andrea

来源：Neues Jahrbuch fur Geologie und Palaontologie-Abhandlungen, 2011, 261(2): 165-176.

DOI：10.1127/0077-7749/2011/0156

• Echinoidea
• Danian
• Roca Formation
• Patagonia
• Argentina
• new species

Stratigraphically well-constrained echinoids from the Roca Formation in the province of Rio Negro (Patagonia, Argentina) are analysed in detail. The poorly known Linthia? joannishoehmi OPPENHEIM in BOHM, 1903, recently reassigned to Paraster, is demonstrated to comprise in fact two distinct species, Linthia? joannishoehmi and Linthia parmae n. sp. In addition, specifically indeterminate species of Plesiaster and Hemiaster and a basal holasteroid are recorded. The analyses of calcareous nannofossil assemblages of the echinoid-bearing strata document their early Paleocene (Danian) age, which has an impact on patterns of survivorship across the K/Pg boundary.

• 出版日期2011-8