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Killifishes and Live-Bearers: Cyprinodontiformes

Green Swordtail (xiphophorus Hellerii): Species Accounts



Physical characteristics: Male green swordtails have a long extension on the bottom of the tail fin that forms a sword. Males grow to 51/2 inches (14 centimeters) in total length, the sword being 1½ to 3 inches (4 to 8 centimeters) long. Females grow to 6 inches (16 centimeters). Both sexes have a grayish green background color. Males have two lines of reddish dots on a squared-off dorsal fin and a line of bright to dark red along the entire body. The sword is shiny yellowish green bordered in black.



Geographic range: The native home of green swordtails is Mexico and northwestern Honduras.


Habitat: Green swordtails live in rivers, streams, warm springs and their runoffs, canals, and ponds with heavy plant life.

The dominant male in a group of green swordtails drives off rivals in a feeding area or an area where females have grouped. (Hans Reinhard/Bruce Coleman, Inc. Reproduced by permission.)

Diet: Green swordtails eat plants and insects.


Behavior and reproduction: The dominant male in a group of green swordtails drives off rivals in a feeding area or an area where females have grouped. These fish are live-bearers. Males insert their sperm into females. The females can store sperm and produce several broods from a single mating.


Green swordtails and people: Green swordtails are used in the aquarium business and are frequently used in medical research.


Conservation status: Green swordtails are not threatened or endangered. ∎

Additional topics

Animal Life ResourceFish and Other Cold-Blooded VertebratesKillifishes and Live-Bearers: Cyprinodontiformes - Physical Characteristics, Behavior And Reproduction, Conservation Status, Largescale Foureyes (anableps Anableps): Species Accounts - GEOGRAPHIC RANGE, HABITAT, DIET, KILLIFISHES AND LIVE-BEARERS AND PEOP