# Blind Cave Tetra (*Astyanax mexicanus*) The Blind Cave Tetra is a small, blind fish that lives in dark caves. It has no eyes but uses its other senses to find food and navigate. This unique fish is adapted to its dark environment. - **Category:** [Fish](https://www.snappit.app/explore/categories/fish) - **Rarity:** Common - **Danger:** 1/5 · Very low - **Habitat:** Cave Dwelling - **Also known as:** Cave Tetra, Mexican Tetra ![Blind Cave Tetra](https://res.cloudinary.com/drieglelr/image/upload/v1771424769/objects/5919.jpg) ## Appearance The Blind Cave Tetra is a small, pale, and often translucent fish with a torpedo-shaped body. Lacking eyes, its head is smooth, making it visually distinct from its eyed relatives. Its skin can appear pinkish-white due to its lack of pigment. ## Taxonomy - **Kingdom:** Animalia - **Phylum:** Chordata - **Class:** Actinopterygii - **Order:** Characiformes - **Family:** Characidae - **Genus:** Astyanax ## Interesting facts - Baby blind tetras are born with tiny eyes that soon disappear forever! - Blind Cave Tetras descend from fish that once lived on the surface with eyes! - Living deep underground means these fish never see sunlight, ever! - These fish 'see' with their skin, feeling tiny shifts in water pressure! ## Special abilities - **Vibration Navigator:** Blind Cave Tetra can sense tiny water vibrations using a special line of pores on its side, helping it navigate and find prey. - **Super Sniffer:** Blind Cave Tetra has an amazing sense of smell and taste, allowing it to find food even in total darkness. - **Energy Saver:** Blind Cave Tetra does not grow eyes, saving precious energy that helps it survive in resource-scarce cave environments. ## Measurements & details - **Length:** 8-12 cm - **Weight:** 0.01-0.02 kg - **Lifespan:** 2-4 years - **Swim Speed:** 5 km/h - **Water Type:** Freshwater ## Diet & Feeding Blind Cave Tetras are opportunistic hunters, eating tiny insects and other small bits found in caves. - **Primary Foods:** insect larvae, small crustaceans, detritus, organic debris - **Foraging Method:** Foraging ## Ecological connections - **Eats:** Mexican cave amphipod (*Gammarus mexicanus*) — Main food source in cave systems. - **Eats:** Peck's cave amphipod (*Stygobromus pecki*) — Consumes these small cave-dwelling crustaceans. - **Eats:** Mexican cave isopod (*Caecidotea mexicanus*) — Preys on these small, blind invertebrates. ## Traits - [Nonvascular](https://www.snappit.app/explore/traits/nonvascular): This trait characterizes plants lacking specialized vascular tissues (xylem and phloem) for transporting water and nutrients. - [Cave Dwelling](https://www.snappit.app/explore/traits/cave-dwelling): Cave dwelling describes organisms specifically adapted to live in underground cave systems, often exhibiting specialized traits due to lack of light. - [Piscivorous](https://www.snappit.app/explore/traits/piscivorous): Piscivorous organisms are animals that primarily subsist on a diet of fish. - [Thermoregulating](https://www.snappit.app/explore/traits/thermoregulating): Thermoregulating organisms maintain a stable internal body temperature despite fluctuations in the external environment. - [Ancient Lineage](https://www.snappit.app/explore/traits/ancient-lineage): This trait signifies organisms belonging to a very old evolutionary group with ancestors dating back millions of years. - [Echolocation](https://www.snappit.app/explore/traits/echolocation): Echolocation is a biological sonar used by animals to navigate, hunt, and communicate by emitting sound waves and interpreting the echoes. - [Regenerative](https://www.snappit.app/explore/traits/regenerative): Regenerative organisms possess the ability to regrow lost or damaged body parts, tissues, or organs. - [Aquatic](https://www.snappit.app/explore/traits/aquatic): Aquatic habitats encompass environments where organisms live predominantly in water, including oceans, rivers, lakes, and wetlands. - [Nocturnal](https://www.snappit.app/explore/traits/nocturnal): Nocturnal animals are primarily active during the nighttime hours, typically resting or sleeping during the day. ## Collections - [Fish](https://www.snappit.app/explore/collections/fish) ## Safety **Danger:** 1/5 · Very low If exploring caves, always have an adult with you and be cautious in dark areas. ## Frequently Asked Questions ### How to identify Blind Cave Tetra? Look at body shape, where the fins sit and their outline, mouth position, stripes and spots. Young fish and breeding adults can wear different patterns, and aquarium color varieties can look nothing like wild fish. Fish Identifier: upload a photo and compare the visible details. ### How long is Blind Cave Tetra? 8-12 cm ### How much does Blind Cave Tetra weigh? 0.01-0.02 kg ### How long does Blind Cave Tetra live? 2-4 years ### What does Blind Cave Tetra eat? Blind Cave Tetras are opportunistic hunters, eating tiny insects and other small bits found in caves. ### How fast can Blind Cave Tetra swim? 5 km/h ### Where is Blind Cave Tetra usually found? Cave Dwelling ### How does Blind Cave Tetra hunt? Foraging ## More Fish - [Rainbow Trout](https://www.snappit.app/explore/rainbow-trout) (*Oncorhynchus mykiss*) - [Brown Trout](https://www.snappit.app/explore/brown-trout) (*Salmo trutta*) - [Brook Trout](https://www.snappit.app/explore/brook-trout) (*Salvelinus fontinalis*) - [Lake Trout](https://www.snappit.app/explore/lake-trout) (*Salvelinus namaycush*) --- Source: [Blind Cave Tetra: Facts & Places to See — Snappit](https://www.snappit.app/explore/blind-cave-tetra)