# Stoplight Loosejaw (*Malacosteus niger*) The Stoplight Loosejaw is a deep-sea fish with a unique feature - its transparent head with green bioluminescent eyes! It uses its glowing eyes to attract prey in the dark depths of the ocean. - **Category:** [Fish](https://www.snappit.app/explore/categories/fish) - **Rarity:** Rare - **Danger:** 2/5 · Low - **Habitat:** Deep Sea ![Stoplight Loosejaw](https://res.cloudinary.com/drieglelr/image/upload/v1771424808/objects/6441.jpg) ## Appearance The Stoplight Loosejaw is a slender, black-bodied deep-sea fish. It has an enormous, unhinged mouth with many sharp teeth and peculiar light-emitting organs below its eyes and on its chin, giving it a unique appearance. ## Taxonomy - **Kingdom:** Animalia - **Phylum:** Chordata - **Class:** Actinopteri - **Order:** Stomiiformes - **Family:** Stomiidae - **Genus:** Malacosteus ## Interesting facts - Even though it's small, its needle-sharp teeth are perfect for gripping slippery prey in the dark! - Its mouth is so big, it has no floor and looks like it's missing part of its head! - The red light it makes is invisible to most other deep-sea creatures, giving it a secret hunting beam! - This fish lives in absolute darkness, where sunlight never reaches, making it a true deep-sea explorer! ## Special abilities - **Red Light Vision:** Stoplight Loosejaw can see red light because it has special eye pigments, helping it find prey that cannot see the red glow. - **Secret Red Headlights:** Stoplight Loosejaw can create its own red light from organs near its eyes, allowing it to search for prey invisibly in deep darkness. - **Super Stretch Jaw:** Stoplight Loosejaw has a jaw that can drop far open and a throat that expands, letting it swallow prey bigger than its head. ## Measurements & details - **Length:** 15-26 cm - **Weight:** 0.05-0.2 kg - **Lifespan:** 5-15 years - **Swim Speed:** 3 km/h - **Maximum Depth:** 2500 m - **Water Type:** Saltwater ## Diet & Feeding A fierce deep-sea hunter, it eats other fish and crustaceans it finds in the dark depths. - **Primary Foods:** Small deep-sea fish, Shrimp, Copepods, Lanternfish - **Foraging Method:** Ambush ## Ecological connections - **Hunts:** Spotted Lanternfish (*Myctophum punctatum*) — A common bioluminescent prey in the deep sea. - **Hunts:** Silver Hatchetfish (*Argyropelecus aculeatus*) — Another deep-sea fish commonly eaten by loosejaws. - **Eaten by:** [Sperm Whale](https://www.snappit.app/explore/sperm-whale) (*Physeter macrocephalus*) — Large deep-diving predator that hunts deep-sea fish. ## Traits - [Piscivorous](https://www.snappit.app/explore/traits/piscivorous): Piscivorous organisms are animals that primarily subsist on a diet of fish. - [Ambush Predator](https://www.snappit.app/explore/traits/ambush-predator): An ambush predator hunts by patiently waiting and concealing itself, then launching a sudden attack when unsuspecting prey comes within range. - [Deep Sea](https://www.snappit.app/explore/traits/deep-sea): Deep sea habitats are characterized by extreme pressure, darkness, and cold temperatures, supporting unique life forms below the sunlit zone. - [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. - [Glowing](https://www.snappit.app/explore/traits/glowing): Pertaining to organisms that emit light through bioluminescence or fluorescence. - [Nocturnal](https://www.snappit.app/explore/traits/nocturnal): Nocturnal animals are primarily active during the nighttime hours, typically resting or sleeping during the day. - [Venomous](https://www.snappit.app/explore/traits/venomous): Venomous organisms produce toxins that are injected into another animal, typically through a bite or sting. ## Collections - [Fish](https://www.snappit.app/explore/collections/fish) ## Safety **Danger:** 2/5 · Low This fish lives in the deep ocean where it's not safe for humans to explore. It's best admired from pictures or videos. ## Frequently Asked Questions ### How to identify Stoplight Loosejaw? 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 Stoplight Loosejaw? 15-26 cm ### How much does Stoplight Loosejaw weigh? 0.05-0.2 kg ### How long does Stoplight Loosejaw live? 5-15 years ### What does Stoplight Loosejaw eat? A fierce deep-sea hunter, it eats other fish and crustaceans it finds in the dark depths. ### How fast can Stoplight Loosejaw swim? 3 km/h ### Where is Stoplight Loosejaw usually found? Deep Sea ### How does Stoplight Loosejaw hunt? Ambush ## 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: [Stoplight Loosejaw: Facts & Places to See — Snappit](https://www.snappit.app/explore/stoplight-loosejaw)