Swordtail, Xiphophorus hellerii Heckel 1848

Other Names: One-spot Livebearer

Swordtail, Xiphophorus hellerii, female above, male below. Source: Queensland Museum. License: all rights reserved

An aquarium fish released into streams in Queensland, New South Wales, South Australia, the Northern Territory and Western Australia. The lower margin of the tail in males is elongated and sword-like. 

Cite this page as:
Vanessa J. Thompson & Dianne J. Bray, Xiphophorus hellerii in Fishes of Australia, accessed 24 May 2024, https://fishesofaustralia.net.au/home/species/3638

Swordtail, Xiphophorus hellerii Heckel 1848

More Info


Native to eastern Central America and introduced to Australia via the aquarium trade. Occurs in the Barron River, Cairns (16º53'S), and scattered localities along QLD coast to Burringbar Creek, northern NSW (28º26'S), also Nhulunbuy (136º47'E), Darwin (130º50'E) and Alice Springs (23º49'S, 133º44'E), NT, and recently recorded from Irwin River (29º13'S), near Geraldton, WA, and northeast of Robe, SA (37º01'S, 139º58'E). Also reported from the Todd River in central Australia in 1982, but apparently not established. 
A tropical species found in warm gently flowing freshwater streams with sparse vegetation over gravel substrates. Also near the edges of freshwater creeks and drains amongst aquatic plants. Can tolerate salinities up to 50% seawater.


Meristic features: Dorsal fin 11-12; Anal fin 8-9; Pectoral fin 12-13; Pelvic fin 6; Gill rakers 18-20.

Body moderately deep and compressed with arched back; mouth upturned and protrusible, lower jaw a little longer than upper; eyes large; gill rakers slender.

Scales cover head and trunk; 26-27 in horizontal row; lateral line absent.

Single dorsal fin, angular, origin about mid-body; posterior dorsal fin rays elongated in males; anal fin smaller than and situated below dorsal in females and forward of dorsal in males; anal fin modified to form gonopodium in males; caudal fin truncate, lower margin elongated in males.


Females to 12 cm SL; Males to 8 cm SL.


Males bright orange overall or olive-brown to greenish with a reddish-orange stripe on sides continuing onto tail; Females orange to olive-brownish.


Omnivorous feeding on small insects, aquatic invertebrates, algae and diatoms from weeds and substrate.


Live-bearers. The front rays of the male’s anal fin are modified to form a gonopodium which is used to internally fertilise eggs; Females are mature at 23 mm SL; greatest spawning activity from October to December with up to 9 broods per year. This species is capable of protogynous (female to male) sex change. Fertilised eggs develop inside the female. Young are born after 5-9 weeks gestation.



Populations have been established in Australia since the early 1960s after deliberate or unintentional release of aquarium specimens.

Similar Species

Small females may resemble the Platy X. maculatus but the base of the tail lacks the dark blotches seen in the Platy. The sword-tail of the male is highly distinctive.


Xiphophorus from the Greek xifos meaning sword and phero meaning carry.

Species Citation

Xiphophorus hellerii Heckel, 1848, Sitzb. K. Akad. Wissen. Wien 1: 291. Type locality: Orizaba, Mexico.


Vanessa J. Thompson & Dianne J. Bray

Swordtail, Xiphophorus hellerii Heckel 1848


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Arthington, A.H. (1989) Diet of Gambusia affinis holbrooki, Xiphophorus helleri, X. maculatus and Poecilia reticulata (Pisces: Poeciliidae) in Streams of Southeastern Queensland, Australia. Asian Fisheries Science 2(2): 193-212

Arthington, A.H. & Llyod L.N. (1989) Introduced Poeciliids in Australia and New Zealand. In: Ecology and Evolution of Livebearing Fishes. Eds G.K. Meffe & F.F. Snelson. pp 333-348. Prentice Hall Englewood Cliffs NJ USA

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Quick Facts

CAAB Code:37244005



Max Size:12 cm


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