Cualac Tessellatus

Datasheet

General Description

The Checkered Pupfish, scientifically known as Cualac Tessellatus, is a species characterized by its local name "cachorrito de Media Luna," which translates to "puppy of Media Luna." It is a relatively non-aggressive fish that can be housed with other hard water species such as goodeids, Xiphophorus, and Poecilia spp. This monotypic species is distinguished by closely-packed, villiform inferior pharyngeal teeth and 17 rakers on the first gill arch.

Aquarium Setup

For optimal maintenance, it is recommended to maintain the Checkered Pupfish in hard water with a pH range of 7.5-8.5 and a temperature range of 20-30°C. The tank should offer enough aquatic plants and cover, such as wool mops, to create broken lines-of-sight. Filtration should be provided with air-powered sponge units to avoid harming eggs or fry. Encouraging the growth of filamentous algae in the tank is beneficial.

Behaviour

In the aquarium, the Checkered Pupfish can be housed alone or in a group without issues. Male territorial behavior during breeding is mainly limited to chasing rather than aggressive biting. This species is not excessively voracious and can coexist with other fish species as long as they are compatible.

Feeding and Diet

The Checkered Pupfish is primarily a micropredator, feeding on small aquatic crustaceans, worms, insect larvae, and zooplankton. In captivity, they accept dried foods but should also be offered live or frozen options like Artemia, Daphnia, or bloodworms. Adding a dried product with added vegetable content is advisable, especially if the tank lacks filamentous algae.

Reproduction & Dimorphism

Breeding the Checkered Pupfish in captivity requires very hard water, and the addition of sulphur, preferably from gypsum rock chunks, aids in egg development. Females are fractional spawners, depositing eggs continuously in warm conditions. Males form temporary territories, displaying vibrant colors to attract females. Males exhibit striking coloration and markings, while females are comparatively plain with minimal dorsal-fin pigmentation.

Habitat and Distribution

Endemic to the Río Verde valley in Central Mexico, the Checkered Pupfish inhabits natural springs with constant temperatures and crystal-clear, hard water fed by groundwater springs. It is found in the Media Luna lagoon system and other smaller lagoons in the area. The species faces endangerment due to habitat degradation by introduced species, such as Oreochromis aureus and Poecilia latipunctata, as well as environmental factors like tourism and agriculture.