Mexican Tetra, also known as Blind Cave Fish, Blind Cave Characin, and Blind Cave Tetra, has the scientific name Astyanax mexicanus.
This freshwater fish belongs to the Characidae family and Characiformes order.
It’s mainly found in Texas and Mexico, living in rivers like the Rio Grande, Neueces, and Pecos.
This fish is quite popular among aquarium owners because of its peaceful nature.
It usually swims in the middle level of water above rocky or sandy surfaces in creeks and rivers.
During winter months, some populations move to warmer waters.
In its natural habitat, this fish eat crustaceans, insects, and worms but will eat a variety of foods when kept in an aquarium.
Some experts have considered Mexican tetra as a subspecies of A. fasciatus or even classified its blind cave form as another species (A. jordani).
But these ideas are not widely accepted due to phylogenetic evidence that contradicts them.
Mexican Tetra Interesting Facts
- Mexican Tetra, or Astyanax mexicanus, is found in Texas and Mexico, living in rivers like the Rio Grande.
- This fish has two forms: sighted (silver) and eyeless (pinkish-white), known as Blind Tetras.
- They prefer subtropical climates with water temperatures between 68°F to 77°F (20°C to 25°C) and pH levels from 6.5 to 8.
- Popular among aquarium owners for their peaceful nature, they eat crustaceans, insects, and worms in the wild.
Mexican Tetra Habitat
Mexican tetra is found in Mexico, which is part of North America. This fish lives in freshwater environments and swims close to the bottom (benthopelagic).
Mexican tetra thrives best in subtropical climates with water temperatures between 68°F to 77°F (20°C to 25°C), pH levels from 6.5 to 8, and hardness up to 30 dGH.
It migrates within rivers (potamodromous) and prefers subtropical climates between 36°N to 24°N latitude.
| Water Temperature: | 68°F to 77°F (20°C to 25°C) |
| Water pH: | 6.5 to 8.0 pH |
| Water Hardness: | Unknown |
Mexican Tetra Physical Characteristics
Size: 2.4 inches (6.0 centimeters)
Mexican tetra can reach a maximum length of 4.7 inches (12.0 centimeters), but most commonly grows to around 2.4 inches (6.0 centimeters) long.
It has a typical silver appearance. However, its blind cave form lacks eyes and pigment, giving it a unique pinkish-white color.
Mexican Tetra Reproduction
Mexican tetras have a unique way of reproducing. They hide their eggs in small cracks and gaps.
Mexican Tetra Scientific Classification
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Actinopterygii |
| Order: | Characiformes |
| Family: | Characidae |
| Genus: | Astyanax |
| Scientific Name: | Astyanax mexicanus |
| Also Known As: | Mexican Tetra, Blind Cave Fish, Blind Cave Characin, Blind Cave Tetra |
| Conservation Status: | Least Concern |