''Microzarkodina'' is an extinct genus of

conodonts Conodonts (Greek ''kōnos'', "cone", + ''odont'', "tooth") are an extinct group of agnathan (jawless) vertebrates resembling eels, classified in the class Conodonta. For many years, they were known only from their tooth-like oral elements, which ...

mainly from the Middle Ordovician of

Baltoscandia Baltoscandian Confederation or Baltoscandia is a geopolitical concept of a Baltic–Scandinavian ( Nordic) union comprising Denmark, Estonia, Finland, Iceland, Latvia, Lithuania, Norway, and Sweden. The idea was proposed by a Swedish Professor ...

. The Microzarkodina apparatus probably consisted of 15 or 17 elements: four P, two or four M and nine S elements. The S elements include different Sa, Sb1, Sb2, and Sc element types.Morphology, evolution and stratigraphic distribution in the Middle Ordovician conodont genus Microzarkodina. Anita Löfgren and Tatiana Tolmacheva, Earth and Environmental Science Transactions of the Royal Society of Edinburgh, Volume 99, Issue 01, March 2008, pages 27-48,

Use in stratigraphy

The base of the

Darriwilian The Darriwilian is the upper stage of the Middle Ordovician. It is preceded by the Dapingian and succeeded by the Upper Ordovician Sandbian Stage. The lower boundary of the Darriwilian is defined as the first appearance of the graptolite species '' ...

, the fourth stage of the Ordovician, lies just above the North Atlantic ''Microzarkodina parva'' conodont zone.

References

External links

* * Ordovician conodonts Ozarkodinida genera {{conodont-stub