Caenogastropoda

Atlantic Triton snail ( Charonia nobilis) feeding on a sea star

The Caenogastropoda are the largest group within the snails ( Gastropoda ). They are a subset of the Apogastropoda ( and sister group of Heterobranchia ). Systema Naturae in 2000, the group superorder rank is assigned. It consists of the two sister groups Sorbeoconcha and Architaenioglossa.

Characterization

The Caenogastropoda are by Ponder and Lindberg 1997 well characterized by 14 synapomorphe features. According to the large number of species, the variation is very large in the case. There are mainly marine snails, a few groups ( Architaenioglossa ) are also found in fresh water.

Subdivision

The group was originally set up by Cox in 1960 at the rank of order. Later writers have the group then considered as a superorder. In Ponder & Lindberg ( 1997), the group is seen not assigned a rank in linneisch - hierarchical sense, but it is only the position established in the pedigree of snails. They only speak of a " clade ", ie a branch. They are justified in the phylogenetic system as the sister group of the Heterobranchia. With this group, the Caenogastropoda be combined to form a monophyletic group Apogastropoda. Also Bouchet & Rocroi (2005 ) indicate the group to no rank. Systema Naturae The 2000 lists the Caenogastropoda again as an order. In the hierarchical system of the Apogastropoda the rank of a class or sub- class infrastructure is assigned:

• Infra class Apogastropoda Salvini - Plawen & Haszprunar, 1987 Superorder Heterobranchia Haszprunar, 1985
• Superorder Caenogastropoda Cox, 1960 Order Architaenioglossa Haller, 1892
• Ponder & Lindberg order Sorbeoconcha, 1997
• Subordination Discopoda P. Fischer, 1884
• Subordination Hypsogastropoda Ponder & Lindberg, 1997 Partial order Littorinimorpha Golikov & Starobogatov, 1975
• Partial order Ptenoglossa J. E. Gray, 1853
• Partial order Neogastropoda Thiele, 1929