Genus Tetrad

Species total:
30
Age range:
2600 - 1.8 MA (obsolete dating)
IRMNG:
find
Name From To Age range
Tetrad sp Proterozoic Hauterivian
Tetrad Late Precambrian Oligocene
Tetrad type 3 Late Ordovician Late Ordovician
Tetrad type C Vavr.,1984 Late Ordovician Late Ordovician
Tetrad type F Late Ordovician Late Ordovician
Tetrad sp. Vavr.,1984 Late Ordovician Late Ordovician
Tetrad type A Late Ordovician Late Ordovician
Tetrad type A Vavr.,1984 Ashgillian Ashgillian
Tetrad sp.3350 Magl.,1967 Middle Llandoverian Lochkovian
Tetrad type B Late Telychian Early Sheinwoodian
Tetrad type 2 Wenlockian Gedinnian
Tetrad type 1 Wenlockian Middle Cenomanian
Tetrad sp.B Wenlockian Gedinnian
Tetrad sp.C Wenlockian Gedinnian
Tetrad sp.D Pridolian Gedinnian
Tetrad sp.1 Rubi.& Stee.,2002 Late Ludlovian Early Pridolian
Tetrad sp.2 Emsian Emsian