#rivulus__rivulu  found in small streams of tropical America; often kept in aquariums; usually hermaphroditic
  supertype:  killifish  small mostly marine warm-water carp-like schooling fishes; used as bait or aquarium fishes or in mosquito control
  member of:  genus_Rivulus  killifish
     member of:  family_Cyprinodontidae__Cyprinodontidae  large family of small soft-finned fishes; killifishes; flagfishes; swordtails; guppies
        member of:  order_Cypriniformes__Cypriniformes  an order of animals including almost entirely freshwater fishes: characins; loaches; carp; suckers; sometimes classified as a suborder of Ostariophysi
           member of:  superorder_Malacopterygii__Malacopterygii  an extensive group of teleost fishes having fins supported by flexible cartilaginous rays
              member of:  subclass_Teleostei__Teleostei  large diverse group of bony fishes; includes most living species
                 member of:  class_Osteichthyes__Osteichthyes  a class of fish having a skeleton composed of bone in addition to cartilage
                    member of:  subphylum_Vertebrata__Vertebrata__Craniata__subphylum_Craniata  fishes; amphibians; reptiles; birds; mammals
                       member of:  phylum_Chordata__Chordata  comprises true vertebrates and animals having a notochord
                          member of:  kingdom_Animalia__Animalia__animal_kingdom  taxonomic kingdom comprising all living or extinct animals

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