The
Bashkirian, the oldest age of the
Pennsylvanian (also known as Upper Carboniferous), contains six biozones based on conodont index fossils, two of which are named after
Declinognathodus species: • the zone of
Declinognathodus marginodosus, • the zone of
Declinognathodus noduliferus. The
GSSP point is at
Arrow Canyon, Nevada, USA, with the first appearance of
Declinognathodus noduliferus sensu lato. The base of the
Moscovian, the second stage in the Pennsylvanian, is close to the first appearances of the conodonts
Declinognathodus donetzianus Nemirovskaya, 1990 and
Diplognathodus ellesmerensis Bender, 1980. The Moscovian can biostratigraphically be divided into five conodont biozones, one of which is named after a
Declinognathodus species : the zone of
Declinognathodus donetzianus. The
GSSP candidate sections are the
Ural Mountains or in
Naqing (Nashui), Luodian County, Guizhou, China. ==References==