Evolution of Mollusca


Evolution of Mollusca
Diagram of primitive mollusc viewed from left side. Hypothetical mollusc ancestor. From Encyclopædia Britannica Eleventh Edition.

The current understanding of molluscan phylogeny is shown below.

Horizontal cladogram (source:[1]):

 Mollusca 
 Aplacophora 

Solenogastres



Caudofoveata



 Testaria 
Polyplacophora 

Palaeoloricata



Neoloricata



Conchifera 

Monoplacophora


 (unnamed) 
 Cyrtosoma 

Gastropoda



Cephalopoda



 Diasoma 

Rostroconchia


 (unnamed) 

Scaphopoda



Bivalvia








Basal Mollusca phylogeny.

Early organisms which have been compared to molluscs include Kimberella and Odontogriphus.

References

Further reading