Moon Jelly
Aurelia aurita
Meet the Moon Jelly
The Moon Jelly, scientifically known as Aurelia aurita, is a translucent, saucer-shaped jellyfish commonly found in coastal waters around the world. It is easily recognized by its delicate, umbrella-like bell that displays four distinct horseshoe-shaped gonads visible through its body. Moon jellies drift gracefully with ocean currents, using their tentacles to capture small plankton and other microscopic prey. Although they possess stinging cells, their sting is typically harmless to humans, making them a popular subject in public aquariums. Their adaptability to various salinities and temperatures contributes to their widespread distribution.
Wikipedia Data 🎥 6 Videos 📚 3 Sources Classification
Invertebrate
Habitat
Coastal ocean waters
Diet
Carnivore
Lifespan
1-2 years
Conservation
Least Concern
Weight
100–400 grams
📖Fascinating Facts
Drifting Lifestyle
Moon jellies are planktonic, meaning they drift with the currents rather than actively swimming long distances.
No Brain or Heart
They lack a central nervous system and a circulatory system, relying on a simple nerve net to sense their environment.
Impressive Regeneration
If injured, moon jellies can regenerate lost tentacles and even parts of their bell over time.
📋Detailed Description
Aurelia aurita, commonly known as the Moon Jelly, is a scyphozoan jellyfish characterized by its nearly transparent, saucer-shaped bell, which typically measures 25–40 cm (10–16 in) in diameter but can range from 5 to 40 cm depending on environmental conditions. The bell is soft and gelatinous, edged with hundreds of short, fine tentacles and four conspicuous oral arms extending from the center. The most distinctive feature is the presence of four horseshoe-shaped gonads, visible through the bell, which are actually the reproductive organs. The body is composed of over 95% water, with a simple tissue structure lacking true organs, bones, or a centralized nervous system. Instead, Aurelia aurita possesses a decentralized nerve net and rhopalia—sensory structures that detect light, gravity, and chemicals. Locomotion is achieved by rhythmic pulsations of the bell, though the species primarily drifts with ocean currents. Moon jellies are found in coastal and estuarine waters worldwide, thriving in a range of salinities and temperatures, from temperate to tropical regions. They are opportunistic carnivores, feeding on zooplankton, small crustaceans, fish larvae, and eggs, which they capture using their tentacles and mucus-covered oral arms. Their life cycle alternates between a sessile polyp stage and a free-swimming medusa stage, contributing to their ecological resilience and ability to rapidly colonize new environments.
💡 Did you know?
Despite their simple biology, moon jellies can survive in low-oxygen waters where many other marine animals cannot.
🔬Research & Sources
Wikipedia Summary
Aurelia aurita is a species of the family Ulmaridae. All species in the genus are very similar, and it is difficult to identify Aurelia medusae without genetic sampling; most of what follows applies equally to all species of the genus.
Last Modified: 5/19/2025
🎭Behavior & Social Structure
Moon jellies are primarily passive drifters, relying on ocean currents for movement, but they can actively pulse their bells to ascend or descend in the water column. They exhibit diel vertical migration, often rising toward the surface at night to feed and descending during the day to avoid predators and intense sunlight. Feeding involves trapping prey in mucus on the bell and tentacles, then transferring it to the oral arms for ingestion. Aurelia aurita can form large aggregations or 'blooms,' sometimes numbering in the thousands, especially in nutrient-rich or eutrophic waters. These blooms can significantly impact local ecosystems by consuming large quantities of plankton. While not social in the mammalian sense, moon jellies tolerate close proximity to conspecifics and other jellyfish species, especially during blooms. They are preyed upon by sea turtles, certain fish, and birds, but their gelatinous bodies and mild venom offer some protection.
👶Reproduction & Life Cycle
Aurelia aurita exhibits a complex life cycle with both sexual and asexual reproduction. Sexual reproduction occurs in the medusa stage, where males release sperm into the water column, which females collect with their oral arms for internal fertilization. Fertilized eggs develop into planula larvae, which settle onto substrates and transform into sessile polyps (scyphistomae). Polyps can reproduce asexually through budding or strobilation, a process in which they segment and release juvenile medusae (ephyrae) into the water. There is little to no parental care; offspring are independent from the earliest stages. Breeding can occur year-round in tropical regions but is often seasonal in temperate zones, peaking in spring and summer when water temperatures rise.
🛡️Adaptations & Survival
Moon jellies possess several adaptations for survival. Their translucent bodies provide camouflage in open water, reducing predation risk. The decentralized nerve net and rhopalia allow them to respond rapidly to environmental stimuli despite lacking a brain. Their ability to tolerate wide ranges of salinity (as low as 6 ppt) and temperature (from 6°C to over 30°C) enables them to inhabit estuaries, harbors, and coastal lagoons. The production of large numbers of offspring through both sexual and asexual means allows rapid population increases under favorable conditions. Their mild venom is effective against small prey but generally harmless to humans, reducing unnecessary energy expenditure on defense.
🎨Cultural Significance
Moon jellies have been featured in art, literature, and public aquariums due to their ethereal appearance and gentle nature. In some cultures, jellyfish symbolize transience and the mysteries of the ocean. They are used in educational programs to illustrate simple nervous systems and cnidarian biology. In certain East Asian cuisines, related jellyfish species are consumed, but Aurelia aurita is not commonly harvested for food. Their blooms can impact fisheries and tourism, occasionally leading to negative perceptions.
🔬Recent Research & Discoveries
Recent research has focused on the genetic diversity within the Aurelia genus, revealing cryptic species and challenging traditional morphological identification. Studies have examined the impact of environmental variables on bloom dynamics, with evidence that nutrient enrichment and climate change are key drivers. The moon jelly’s simple nervous system is a model for neurobiological research, and their resilience to hypoxia is of interest for understanding ecological responses to ocean deoxygenation. Ongoing studies are investigating the role of jellyfish in biogeochemical cycles and their interactions with human-altered marine environments.
🎥Wildlife Videos
Vicious Beauties - The Secret World of the Jellyfish | Free Documentary Nature
Vicious Beauties - The Secret World of the Jellyfish | Ocean Documentary The family of the jellyfish or medusae are not only the ...
Free Documentary - Nature
A Jellyfish Explosion | Alaska's Deadliest
About National Geographic Wild: National Geographic Wild is a place for all things animals and for animal-lovers alike. Take a ...
Nat Geo Animals
Jellyfish rule - Nature of things
Jellyfish are one of earth's most ancient animals, and many scientists predict they will be here long after we're gone. Could these ...
The Nature of Things
Into the Abyss: Creatures of the Midwater (Full Movie)
In the deep ocean, life is divided between very different worlds inhabited by weird and wonderful deep sea creatures. In the ...
Natural World Facts
National Geographic Attack Of The Giant Jellyfish Full Documentary HD
Boutros Azimova
Immortal creature of Animal kingdom ! Who lives forever ! Wildlife Documentary
The immortal jellyfish scientifically known as turritopsis doni is a remarkable creature that has captured the imagination of ...
TheWildlifeScience
🌍Habitat Information
The Moon Jelly typically inhabits Coastal ocean waters environments. Moon Jellys have adapted to their environments with specialized features and behaviors.
Primary Habitat:
Coastal ocean waters
More detailed habitat information will be available soon.
🛡️Conservation Status
The Moon Jelly is currently classified as Least Concern. Conservation efforts are crucial for preserving this species for future generations.
Common Threats:
- 🏠Habitat loss and fragmentation
- 🌡️Climate change impacts
- 🎯Hunting and poaching
- 🏭Human-wildlife conflict
⚠️Threats & Conservation Challenges
While currently listed as Least Concern, Aurelia aurita faces localized threats from pollution, habitat degradation, and climate change. Eutrophication from agricultural runoff can lead to hypoxic zones, which moon jellies tolerate better than many competitors, sometimes resulting in population explosions. Overfishing of natural predators and competitors may also facilitate blooms. Conversely, coastal development and pollution can destroy polyp habitats, potentially reducing recruitment. Climate change may alter distribution patterns, with warming seas expanding their range but also introducing new ecological pressures.
🔬Scientific Classification
Scientific Name
Aurelia aurita
Classification Hierarchy
🔍 About Taxonomic Classification
Taxonomic classification is a hierarchical system used by scientists to classify and organize living organisms based on shared characteristics and evolutionary relationships.
The system moves from broad categories (Kingdom) to increasingly specific ones, with each animal's scientific name typically consisting of its Genus and species.
📝Community Notes
Share your observations and insights about the Moon Jelly with our community of wildlife enthusiasts.
Join Our Community
Sign in to share your observations and connect with fellow wildlife enthusiasts.
Sign In to ContributeNo community notes yet
Be the first to share your observations about the Moon Jelly!
Explore Moon Jelly
Select a tab above to learn more about this amazing animal.
📸Photo Gallery
No photos available for this animal yet.
🌟Discover More Wildlife
Continue your journey of discovery with more fascinating animals from our database