Use in stratigraphy
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''. TheReferences
* Early evolution of Declinognathodus close to the Mid-Carboniferous Boundary interval in the Barcaliente type section (Spain). Javier Sanz-López and Silvia Blanco-Ferrera, Palaeontology, September 2013, Volume 56, Issue 5, pages 927–946, * Conodont chronostratigraphical resolution and Declinognathodus evolution close to the Mid-Carboniferous Boundary in the Barcaliente Formation type section, NW Spain. Javier Sanz-López, Silvia Blanco-Ferrera and Luis C. Sánchez de Posada, Lethaia, October 2013, Volume 46, Issue 4, pages 438–453,External links
* * Conodont genera Pennsylvanian conodonts {{conodont-stub