| 
Suborder:
 | 
Prolecanitina 
 | 
| 
Superfamily:
 | 
Medlicottioidea 
 | 
| 
Family:
 | 
Medlicottiidae 
 | 
| 
Subfamily:
 | 
Medlicottiinae 
 | 
| 
Genus:
 | 
Syrdenites 
 | 
| 
Species:
 | 
sp. | 
| 
Qualifier:
 | 
in | 
| 
Author:
 | 
	div. authors 	 
 | 
| 
Lower Boundary:
 | 
AZB base Araxoceras beds, 260.4 million years
 
 | 
| 
Upper Boundary:
 | 
AZB Araxoceras--Vedioceras beds, 256 million years
 
 |