title: Choanomphalus maacki
text: # Choanomphalus maacki
  
  Choanomphalus maacki is a species of freshwater air-breathing snail, an aquatic pulmonate gastropod mollusk in the family Planorbidae, the ram's horn snails, or planorbids.
  
  Choanomphalus maacki is the type species of the genus Choanomphalus.
  
  ## Subspecies
  
  * Choanomphalus maacki maacki Gerstfeldt, 1859
  * Choanomphalus maacki andrussowianus (Lindholm, 1909)
  * Choanomphalus maacki elatior Lindholm, 1909
  
  However, IUCN Red List 2013 lists these three as synonyms.
  
  ## Distribution
  
  This species is found in Lake Baikal, Russia. Its natural habitats are freshwater lakes and river mouths.
  
  ## Description
  
  The width of the shell is 5–6 mm. The height of the shell is 2.5–3.0 mm.
  
  | Apical view of the shell. | Umbilical view of the shell. |
  | - | - |
  