Dwarf sword bearer

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Dwarf sword bearer
Systematics
Order : Toothpies (Cyprinodontiformes)
Subordination : Cyprinodontoidei
Family : Viviparous toothcarps (Poeciliidae)
Subfamily : Live-bearing toothcarps (Poeciliinae)
Genre : Xiphophorus
Type : Dwarf sword bearer
Scientific name
Xiphophorus pygmaeus
Hubbs & Gordon, 1943

The dwarf swordtail ( Xiphophorus pygmaeus ) is a species of fish from the subfamily of the viviparous toothcarps (Poeciliinae). The scientific species name points to its relatively small body size in relation to other Xiphophorus species ( Latin pygmaeus " thumb ", from ancient Greek πυγμαῖος pygmaíos "fist-sized").

Appearance and Distribution

Dwarf swordtails have a less high back than other species of the genus. This makes them look comparatively slim. The body color is mostly gray-brown. The males usually carry no or only an indicated (1–2 mm long) sword (elongated lower caudal fin rays ) and are up to 3.5 cm long, they show a rather elongated physique. There is also a yellow color morph among the males. As is common with most toothcarps, males can be recognized by their narrow gonopodium , which is used for internal fertilization. Adult females can reach a total length of 4.5 cm, are significantly higher back than the males, and their anal fin is triangular.

The distribution area extends from the Rio Axtla (a tributary of the Rio Moctezuma in central Mexico ) and its tributaries to Guatemala . These are fast-flowing waters with a muddy bottom and a temperature of around 23 ° C.

Keeping and breeding

Since it is a small species, it should not be kept with rough fish. The pool should be well planted, offer hiding places and hold at least 40 liters of water. It is best to breed the animals in a group of several males and females. Then reproduction works best. The females release fry every 26–30 days, which are relatively large at 6–7 mm in length. For this reason, they are usually safe from being stalked by their parents. The animals are omnivorous ( omnivores ), but breeding success can be significantly increased by a varied diet and, above all, live food. Like to be brine shrimp (Artemia salina) taken for rearing up their entkapsulierten have nauplii proved. These fish do not have great demands on the water parameters (temperature 18–23 ° C, GH up to 15 ° dH, pH 7–8), but a regular partial water change is recommended.

literature

  • Rüdiger Riehl , Hans A. Baensch (Ed.): Aquariums Atlas. 4th edition. Melle 1983.
  • Manfred K. Meyer, Lothar Wischnath, Wolfgang Foerster: Livebearers ornamental fish. Kinds of the world. Keeping-care-breeding. Melle 1985.

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