# Mnemiopsis leidyi The Mnemiopsis leidyi, also known as the sea walnut, is a jelly-like creature that lives in the ocean. It has a beautiful, glowing body and can be found swimming in warm coastal waters. - **Category:** [Invertebrate](https://www.snappit.app/explore/categories/invertebrate) - **Rarity:** Common - **Danger:** 2/5 · Low - **Snaps:** 2 - **Habitat:** Coastal areas - **Also known as:** Sea Walnut ![Mnemiopsis leidyi](https://commons.wikimedia.org/w/index.php?title=Special:Redirect/file/Sea_walnut%252C_Boston_Aquarium.jpg&width=800) Photo: Steven G. Johnson, CC BY-SA 3.0 · [Wikimedia Commons](https://commons.wikimedia.org/wiki/File:Sea_walnut%252C_Boston_Aquarium.jpg) ## Appearance The Mnemiopsis leidyi is a transparent, jelly-like animal with an oval body and two distinct oral lobes. It has eight rows of iridescent comb plates that shimmer with rainbow colors. Unlike true jellyfish, it lacks stinging tentacles. ## Taxonomy - **Kingdom:** Animalia - **Phylum:** Ctenophora - **Class:** Tentaculata - **Order:** Lobata - **Family:** Bolinopsidae - **Genus:** Mnemiopsis ## Interesting facts - It doesn't have a brain or bones, just a simple jelly body! - It's called a 'comb jelly' because it uses tiny, hair-like combs to move through water! - Mnemiopsis leidyi is a super speedy eater, consuming huge amounts of tiny ocean creatures! - This amazing animal can be both a male and female at the same time! ## Special abilities - **Ocean Rainbow:** Mnemiopsis leidyi has rows of tiny beating hairs that refract light, creating a shimmering, rainbow effect as it swims. - **Nighttime Glow:** Mnemiopsis leidyi can produce its own light (bioluminescence) that helps them glow in the dark ocean depths. - **Rapid Reproduction:** Mnemiopsis leidyi can quickly create many offspring on its own, which helps them spread rapidly in new areas. - **Sticky Food Net:** Mnemiopsis leidyi has wide oral lobes that act like a net to funnel tiny plankton into its mouth for food. ## Measurements & details - **Size:** 20-100 mm - **Lifespan:** 60-180 days - **Leg Count:** 0 ## Diet & Feeding It gulps down tiny plankton and larvae using a wide mouth, helping clear the water. - **Primary Foods:** Zooplankton, Copepods, Fish larvae, Other small invertebrates - **Foraging Method:** Filter feeding ## Ecological connections - **Eats:** copepod (*Acartia tonsa*) — Consumes vast quantities of these small crustaceans from the water. - **Eaten by:** Beroid comb jelly (*Beroe ovata*) — This specialized predatory comb jelly actively hunts and eats it. - **Eats:** [European anchovy](https://www.snappit.app/explore/european-anchovy) (*Engraulis encrasicolus*) — Preys on the eggs and larvae of this commercially important fish. ## Traits - [Social](https://www.snappit.app/explore/traits/social): Social animals live in organized groups, cooperating for survival benefits such as foraging, defense, and raising offspring. - [Filter Feeder](https://www.snappit.app/explore/traits/filter-feeder): Filter feeders obtain nutrients by straining suspended food particles and small organisms from water. - [Coastal](https://www.snappit.app/explore/traits/coastal): Coastal habitats are dynamic environments located along the interface between land and sea, influenced by tides, waves, and saltwater. - [Carnivorous](https://www.snappit.app/explore/traits/carnivorous): This trait identifies organisms whose diet consists entirely or primarily of animal tissue. - [Diurnal](https://www.snappit.app/explore/traits/diurnal): Diurnal animals are primarily active during daylight hours, typically resting or sleeping at night. - [Keystone Species](https://www.snappit.app/explore/traits/keystone-species): Describes a species whose presence and role have a disproportionately large effect on its environment. - [Aquatic](https://www.snappit.app/explore/traits/aquatic): Aquatic habitats encompass environments where organisms live predominantly in water, including oceans, rivers, lakes, and wetlands. - [Marine](https://www.snappit.app/explore/traits/marine): Marine habitats encompass all saltwater environments of the Earth's oceans, supporting an immense diversity of aquatic life. - [Glowing](https://www.snappit.app/explore/traits/glowing): Pertaining to organisms that emit light through bioluminescence or fluorescence. - [Invasive](https://www.snappit.app/explore/traits/invasive): Invasive species are non-native organisms that cause harm to the environment, economy, or human health. ## Collections - [Insects](https://www.snappit.app/explore/collections/insects) ## Safety **Danger:** 2/5 · Low If you see one on the beach, don't touch it! They can sting. ## Frequently Asked Questions ### How to identify Mnemiopsis leidyi? Compare body symmetry, shells, segments, legs, tentacles and how the animal moves. Invertebrates span many unrelated groups, so start with body structure. Invertebrate Identifier: upload a photo and compare the visible details. ### How big is Mnemiopsis leidyi? 20-100 mm ### How long does Mnemiopsis leidyi live? 60-180 days ### What does Mnemiopsis leidyi eat? It gulps down tiny plankton and larvae using a wide mouth, helping clear the water. ### Where is Mnemiopsis leidyi usually found? Coastal areas ### How does Mnemiopsis leidyi hunt? Filter feeding ### How many legs does Mnemiopsis leidyi have? 0 ## Where to spot - [Fort Monroe National Monument](https://www.snappit.app/guides/places/fort-monroe-national-monument) — Virginia, US · National Park - [Jamestown Exposition](https://www.snappit.app/guides/places/jamestown-exposition) — Virginia, US · Historic District ## More Invertebrate - [Coral](https://www.snappit.app/explore/coral) - [Crab Spider](https://www.snappit.app/explore/crab-spider) (*Mecaphesa asperata*) - [Garden Spider](https://www.snappit.app/explore/garden-spider) (*Araneus diadematus*) - [Brown Recluse Spider](https://www.snappit.app/explore/brown-recluse-spider) (*Loxosceles reclusa*) --- Source: [Mnemiopsis leidyi: Facts & Places to See — Snappit](https://www.snappit.app/explore/mnemiopsis-leidyi)