A new birkeniid anaspid from the Upper Silurian of Skåne, south Sweden
DOI | 10.1080/11035890301252057 |
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Aasta | 2003 |
Ajakiri | GFF |
Köide | 125 |
Number | 2 |
Leheküljed | 57-61 |
Tüüp | artikkel ajakirjas |
Eesti autor | |
Keel | inglise |
Id | 7367 |
Abstrakt
A new anaspid, Ramsaasalepis porosa gen. et sp. nov. is described from the Upper Silurian Öved-Sandstone Formation at Ramsåsa, Skåne, south Sweden. Ramsaasalepis is based on a number of disarticulated scales and plates, characterised by its ridge-like scale sculpture with fine lateral ridgelets. Its histology is also unique, with a well-developed vascular canal system that differs from that of all other known birkeniid anaspids. Ramsaasalepis is probably closest related to Septentrionia Blom, Märss & Miller 2002 and Tahulalepis Blom, Märss & Miller 2002 based mainly on the ridged scale sculpture, well-developed vascular canal system and stratigraphical range. The refined fossil record of anaspids is discussed, emphasising on the recognition of morphological trends that correlates badly with previously suggested phylogenies.