All fish / Poeciliidae

Cortez swordtail

Xiphophorus cortezi

Also known as cortez swordtail, cortezi swordtail, x. cortezi, コルテジィ, 科特斯剑尾鱼

This is a small wild swordtail with an olive to yellowish body, a zigzag lateral line and often black spots along the flanks. Males carry a short, upturned sword edged in black. Hobbyists keep it because it is a natural, unhybridised species from flowing upland streams and is less often seen than the domestic swordtails.

Care at a glance

Care level

Moderate

Temperament

Peaceful

Adult size

5 cm

Temperature

20 to 26 °C

pH

7 to 8

Smallest tank

80 litres

Keep as

Small group with more females than males

Diet

Omnivore: flake, small live and frozen foods, algae and vegetable matter

Swims

Middle of the tank

Lifespan

2 to 4 years

Water

Freshwater

Wild range

Mexico: Río Pánuco basin (San Luis Potosí, Hidalgo, Querétaro)

Breeding

It is a livebearer, and females give birth to small broods of fully formed young every four weeks or so. Breeding is easy in clean, well-oxygenated water, and dense plants help the fry survive.

Good to know

Keep it apart from other Xiphophorus species so pure wild lines are preserved, because it hybridises readily. It prefers clean, moving, cooler water and does not cope with poor water quality.