+-------------------------------- Neotrigonia_margaritacea   
  |                                                            
  |                             +-- Castalia_stevensi          
  |                       +-----+                              
  |                       |     +-- Diplodon_gratus            
  |  +--------------------+                                    
--+  |                    |  +----- Echyridella_menziesii      
  |  |                    +--+                                 
  |  |                       |  +-- Velesunio_angasi           
  |  |                       +--+                              
  |  |                          +-- Lortiella_rugata           
  |  |                                                         
  |  |                          +-- Mutela_dubia               
  +--+              +-----------+                              
     |              |           +-- Mutela_rostrata            
     |  +-----------+                                          
     |  |           |  +----------- Etheria_elliptica          
     |  |           +--+                                       
     |  |              |  +-------- Mulleria_rivoli            
     |  |              +--+                                    
     |  |                 |  +----- Monocondylaea_minuana      
     |  |                 +--+                                 
     +--+                    |  +-- Anodontites_trigona        
        |                    +--+                              
        |                       +-- Anodontites_guanarensis    
        |                                                      
        |  +----------------------- Coelatura_aegyptiaca       
        |  |                                                   
        |  |  +-------------------- Pseudomulleria_dalyi       
        +--+  |                                                
           |  |              +----- Anodonta_cygnea            
           |  |  +-----------+                                 
           +--+  |           |  +-- Strophitus_undulatus       
              |  |           +--+                              
              |  |              +-- Pyganodon_grandis          
              |  |                                             
              +--+  +-------------- Gonidea_angulata           
                 |  |                                          
                 |  |           +-- Unio_pictorum              
                 |  +-----------+                              
                 |  |           +-- Unio_tumidus               
                 |  |                                          
                 +--+           +-- Cumberlandia_monodonta     
                    |  +--------+                              
                    |  |        +-- Margaritifera_margaritifera
                    |  |                                       
                    |  |  +-------- Toxolasma_lividum          
                    |  |  |                                    
                    +--+  +-------- Amblema_plicata            
                       |  |                                    
                       |  |     +-- Glebula_rotundata          
                       |  +-----+                              
                       |  |     +-- Cyrtonaias_tampicoensis    
                       |  |                                    
                       +--+  +----- Potamilus_alatus           
                          +--+                                 
                          |  |  +-- Ortmanniana_ligamentina    
                          |  +--+                              
                          |     +-- Ligumia_recta              
                          |                                    
                          |  +----- Quadrula_quadrula          
                          |  |                                 
                          +--+  +-- Eurynia_dilatata           
                             |  |                              
                             +--+-- Pleurobema_clava           
                                |                              
                                +-- Fusconaia_flava