title: Dianella (gastropod)
text: # Dianella (gastropod)
  
  Dianella is a little-known genus of small freshwater snails with a gill and an operculum, aquatic gastropod molluscs in the family Hydrobiidae.
  
  ## Distribution
  
  These are European freshwater snails; they occur in southeastern Europe, from northern Italy, through the Balkans, to the Black Sea and the Caspian Sea
  
  ## Description
  
  Their relatively big shell has an onic or turriform shape with a common, prominent, spiral sculpture. The radula shows a rhachidian tooth with no basal cusps. Their stomach has a caecal appendix at its pyloric end. They have a Hydrobia-like central nervous system, a simple penis and a characteristic, big seminal receptacle at the end of a prominent spiral of the coiled oviduct.
  
  ## Species
  
  Species within the genus Dianella include:
  
  * † Dianella gracilis (Pavlović, 1903)
  * Dianella schlickum Schütt, 1962
  * Dianella thiesseana Kobelt, 1878
  
  ### Species brought into synonymy
  
  * † Dianella crassa (Burgerstein, 1877): synonym of † Prososthenia crassa Burgerstein, 1877
  * † Dianella nodosa (Burgerstein, 1877): synonym of † Prososthenia nodosa Burgerstein, 1877
  * † Dianella reticulata (Burgerstein, 1877): synonym of † Prososthenia reticulata Burgerstein, 1877
  * † Dianella suessi (Burgerstein, 1877): synonym of † Prososthenia suessi Burgerstein, 1877
  