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The Freshwater Mussels (Unionoida) of the World (and other less consequential bivalves)

FM(U)otW(aolcb) is the web version of the MUSSEL Project Database. Follow the links to browse the data or use the custom Google search field. Either way, you win!

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Bivalvia | Unionida | Unionoidea | Unionidae | Ambleminae | Quadrulini

genus Megalonaias Utterback, 1915: cladomics
     2 Recent valid species (2 total species)

Cladomics Summary

number of species = 2 (2 total)
analyzed in 30 cladograms in 20 publications
maximum number of terminals in an analysis = 2 (mean = 1.07, median = 1)

Basic Monophyly

number of cladograms that test basic monophyly (i.e., more than 1 included species) = 2
maximum number of included terminals = 2, (mean = 2 median = 2)
proportion of cladograms that support basic monophyly = 1

Campbell & Lydeard, 2026 [Publ 4810], fig. 6-14

** Top Monophyly Cladogram **

iTtTbiriSoTroTroSiD
2203630192--
              +-------- Uniomerus                 
  +-----------+                                   
  |           |  +----- Megalonaias_nickliniana__2 **
  |           +--+                                
  |              |  +-- Megalonaias_nervosa **       
  |              +--+                             
  |                 +-- Megalonaias_nickliniana__1 **
  |                                               
  |                 +-- Theliderma_johnsoni       
  |        +--------+                             
--+        |        +-- Theliderma_metanevra      
  |        |                                      
  |  +-----+        +-- Quadrula_nobilis          
  |  |     |  +-----+                             
  |  |     |  |     +-- Quadrula_verrucosa        
  |  |     +--+                                   
  |  |        |  +----- Theliderma_cylindrica     
  |  |        +--+                                
  |  |           |  +-- Quadrula_fragosa          
  +--+           +--+                             
     |              +-- Quadrula_quadrula         
     |                                            
     |           +----- Pustulosa_kieneriana      
     |  +--------+                                
     |  |        |  +-- Pustulosa_infucata        
     |  |        +--+                             
     +--+           +-- Pustulosa_kleiniana       
        |                                         
        |  +----------- Cyclonaias                
        |  |                                      
        +--+        +-- Pustulosa_pustulosa       
           |  +-----+                             
           |  |     +-- Pustulosa_succissa        
           +--+                                   
              |  +----- Pustulosa_nodulata        
              +--+                                
                 |  +-- Pustulosa_necki           
                 +--+                             
                    +-- Pustulosa_petrina

Neemuchwala et al., 2023 [Publ 4292], fig. 2

** Top Sister-Group Cladogram **

iTtTbiriSoTroTroSiD
110126212--
  +-------------- Megalonaias_nervosa **
--+                                  
  |  +----------- Uniomerus          
  +--+                               
     |  +-------- Theliderma         
     +--+                            
        |  +----- Cyclonaias         
        +--+                         
           |  +-- Quadrula           
           +--+                      
              +-- Pustulosa

Pfeiffer et al., 2018 [Publ 3835], fig. 2

iTtTbiriSoTroTroSiD
2202222--
  +-------- Quadrula               
--+                                
  |  +----- Uniomerus              
  +--+                             
     |  +-- Megalonaias_nervosa **    
     +--+                          
        +-- Megalonaias_nickliniana **

Boyer et al., 2011 [Publ 2718], fig. 3

iTtTbiriSoTroTroSiD
11013461--
  +----------------- Megalonaias_nervosa **
--+                                     
  |  +-------------- Quadrula_quadrula  
  +--+                                  
     |  +----------- Quadrula_verrucosa 
     +--+                               
        |  +-------- Theliderma         
        +--+                            
           |  +----- Pustulosa_pustulosa
           +--+                         
              |  +-- Cyclonaias         
              +--+                      
                 +-- Pustulosa_nodulata

Lydeard et al., 1996 [Publ 2656], fig. 3

iTtTbiriSoTroTroSiD
11012632--
  +----- Megalonaias_nervosa **
--+                         
  |  +-- Quadrula           
  +--+                      
     +-- Theliderma

Campbell et al., 2005 [Publ 2660], fig. 2

iTtTbiriSoTroTroSiD
1101101102--
  +-------------------- Megalonaias_nervosa ** 
  |                                         
--+  +----------------- Uniomerus           
  |  |                                      
  +--+  +-------------- Theliderma          
     |  |                                   
     +--+  +----------- Quadrula_quadrula   
        |  |                                
        |  |        +-- Quadrula_nobilis    
        +--+  +-----+                       
           |  |     +-- Quadrula_verrucosa  
           |  |                             
           +--+  +----- Pustulosa_kieneriana
              |  |                          
              |  |  +-- Cyclonaias          
              +--+--+                       
                 |  +-- Pustulosa_succissa  
                 |                          
                 |  +-- Pustulosa_infucata  
                 +--+                       
                    +-- Pustulosa_kleiniana

Johnson et al., 2018 [Publ 3844], fig. 2

iTtTbiriSoTroTroSiD
110115132--
  +-------------------------- Megalonaias_nervosa ** 
  |                                               
--+  +----------------------- Uniomerus           
  |  |                                            
  +--+  +-------------------- Theliderma          
     |  |                                         
     +--+  +----------------- Quadrula            
        |  |                                      
        |  |           +----- Pustulosa_kieneriana
        +--+  +--------+                          
           |  |        |  +-- Pustulosa_infucata  
           |  |        +--+                       
           |  |           +-- Pustulosa_kleiniana 
           +--+                                   
              |           +-- Pustulosa_pustulosa 
              |  +--------+                       
              |  |        +-- Pustulosa_succissa  
              +--+                                
                 |  +-------- Cyclonaias          
                 +--+                             
                    |  +----- Pustulosa_necki     
                    +--+                          
                       |  +-- Pustulosa_nodulata  
                       +--+                       
                          +-- Pustulosa_petrina

Boyer et al., 2011 [Publ 2718], fig. 4

iTtTbiriSoTroTroSiD
11013761--
-- Megalonaias_nervosa **

Krebs et al., 2003 [Publ 2691], fig. 3

iTtTbiriSoTroTroSiD
11013232--
  +-------- Megalonaias_nervosa ** 
--+                             
  |  +----- Quadrula_quadrula__2
  +--+                          
     |  +-- Quadrula_quadrula__1
     +--+                       
        +-- Theliderma

Lydeard et al., 1996 [Publ 2656], fig. 4

iTtTbiriSoTroTroSiD
11012732--
  +----- Megalonaias_nervosa **
--+                         
  |  +-- Quadrula           
  +--+                      
     +-- Theliderma

Rosenberg et al., 1997 [Publ 2720], fig. 2A

iTtTbiriSoTroTroSiD
11012132--
-- Megalonaias_nervosa **

Mulvey et al., 1997 [Publ 3390], fig. 1_3

iTtTbiriSoTroTroSiD
1101400--
-- Megalonaias_nervosa **

Huang et al., 2002 [Publ 2657], fig. 1

iTtTbiriSoTroTroSiD
11013311--
-- Megalonaias_nervosa **

Lopes-Lima et al., 2019 [Publ 3901], fig. 2

iTtTbiriSoTroTroSiD
110127172--
                          +-- Megalonaias_nervosa ** 
  +-----------------------+                       
  |                       +-- Uniomerus           
  |                                               
--+  +----------------------- Quadrula_quadrula   
  |  |                                            
  |  |                    +-- Quadrula_verrucosa  
  +--+  +-----------------+                       
     |  |                 +-- Quadrula_nobilis    
     |  |                                         
     +--+  +----------------- Theliderma          
        |  |                                      
        |  |           +----- Pustulosa_kieneriana
        +--+  +--------+                          
           |  |        |  +-- Pustulosa_infucata  
           |  |        +--+                       
           +--+           +-- Pustulosa_kleiniana 
              |                                   
              |  +----------- Cyclonaias          
              |  |                                
              +--+        +-- Pustulosa_pustulosa 
                 |  +-----+                       
                 |  |     +-- Pustulosa_succissa  
                 +--+                             
                    |  +----- Pustulosa_nodulata  
                    +--+                          
                       |  +-- Pustulosa_necki     
                       +--+                       
                          +-- Pustulosa_petrina

Huang et al., 2002 [Publ 2657], fig. 2

iTtTbiriSoTroTroSiD
11013311--
-- Megalonaias_nervosa **

Huang et al., 2019 [Publ 3843], fig. 2

iTtTbiriSoTroTroSiD
110119932--
  +----- Quadrula           
--+                         
  |  +-- Megalonaias_nervosa **
  +--+                      
     +-- Uniomerus

Lopes-Lima et al., 2019 [Publ 3901], fig. 3

iTtTbiriSoTroTroSiD
110128182--
-- Megalonaias_nervosa **

Lopes-Lima et al., 2019 [Publ 3901], fig. 4

iTtTbiriSoTroTroSiD
110125152--
  +----------------------------- Megalonaias_nervosa ** 
  |                                                  
--+  +-------------------------- Uniomerus           
  |  |                                               
  +--+  +----------------------- Theliderma          
     |  |                                            
     +--+  +-------------------- Quadrula_quadrula   
        |  |                                         
        |  |                 +-- Quadrula_verrucosa  
        +--+  +--------------+                       
           |  |              +-- Quadrula_nobilis    
           |  |                                      
           |  |           +----- Pustulosa_kieneriana
           +--+  +--------+                          
              |  |        |  +-- Pustulosa_infucata  
              |  |        +--+                       
              |  |           +-- Pustulosa_kleiniana 
              +--+                                   
                 |           +-- Pustulosa_pustulosa 
                 |  +--------+                       
                 |  |        +-- Pustulosa_succissa  
                 +--+                                
                    |  +-------- Cyclonaias          
                    +--+                             
                       |  +----- Pustulosa_necki     
                       +--+                          
                          |  +-- Pustulosa_petrina   
                          +--+                       
                             +-- Pustulosa_nodulata

Rosenberg et al., 1994 [Publ 2719], fig. 3

iTtTbiriSoTroTroSiD
11011832--
-- Megalonaias_nervosa **

Rosenberg et al., 1997 [Publ 2720], fig. 2B

iTtTbiriSoTroTroSiD
11012132--
-- Megalonaias_nervosa **

Serb et al., 2003 [Publ 2659], fig. 2

iTtTbiriSoTroTroSiD
110128131--
  +-------- Megalonaias_nervosa **
--+                            
  |  +----- Theliderma         
  +--+                         
     |  +-- Quadrula           
     +--+                      
        +-- Pustulosa

Szumowski et al., 2012 [Publ 3569], fig. 5

iTtTbiriSoTroTroSiD
110113131--
  +----- Megalonaias_nervosa **
  |                         
--+----- Theliderma         
  |                         
  |  +-- Quadrula           
  +--+                      
     +-- Pustulosa

Huang et al., 2019 [Publ 3843], fig. S3

iTtTbiriSoTroTroSiD
110119732--
  +----- Quadrula           
--+                         
  |  +-- Megalonaias_nervosa **
  +--+                      
     +-- Uniomerus

Serb et al., 2003 [Publ 2659], fig. 3

iTtTbiriSoTroTroSiD
110128131--
  +----------- Megalonaias_nervosa **
  |                               
--+        +-- Quadrula_verrucosa 
  |  +-----+                      
  |  |     +-- Quadrula_nobilis   
  +--+                            
     |  +----- Quadrula_quadrula  
     +--+                         
        |  +-- Theliderma         
        +--+                      
           +-- Pustulosa

Smith, 2021 [Publ 4331], fig. 1

iTtTbiriSoTroTroSiD
11011911--
  +-- Uniomerus          
--+                      
  +-- Megalonaias_nervosa **

Huang et al., 2019 [Publ 3843], fig. S4

iTtTbiriSoTroTroSiD
110119932--
-- Megalonaias_nervosa **

Chase et al., 2018 [Publ 3847], fig. 4

iTtTbiriSoTroTroSiD
11013821--
  +----- Megalonaias_nervosa **
--+                         
  |  +-- Cyclonaias         
  +--+                      
     +-- Pustulosa

Breton et al., 2011 [Publ 3376], fig. 3

iTtTbiriSoTroTroSiD
11013731--
-- Megalonaias_nervosa **

Campbell et al., 2005 [Publ 2660], fig. 1

iTtTbiriSoTroTroSiD
1101101102--
              +-- Megalonaias_nervosa ** 
  +-----------+                       
  |           +-- Uniomerus           
--+                                   
  |  +----------- Theliderma          
  |  |                                
  +--+  +-------- Quadrula            
     |  |                             
     +--+  +----- Pustulosa_kieneriana
        |  |                          
        |  |  +-- Cyclonaias          
        +--+--+                       
           |  +-- Pustulosa_succissa  
           |                          
           |  +-- Pustulosa_infucata  
           +--+                       
              +-- Pustulosa_kleiniana

Pfeiffer et al., 2019 [Publ 3866], fig. 1

iTtTbiriSoTroTroSiD
11013042--
  +----------- Megalonaias_nervosa **
--+                               
  |  +-------- Uniomerus          
  +--+                            
     |  +----- Quadrula_verrucosa 
     +--+                         
        |  +-- Cyclonaias         
        +--+                      
           +-- Quadrula_quadrula
 
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