Eels iceberg

Eels iceberg is an iceberg chart topic. On r/IcebergCharts, the highest-scoring available chart on it, "The Eel Iceberg", was posted by u/PresentBluebird6022 on 19 December 2025 and had about 11 upvotes when it was collected. A text version, "Eel" by FishIDK, is hosted on IcebergThreads, where it had 645 views as of 29 October 2026.

The IcebergThreads author describes it as: "Eels. Eels are a large group of fish in the order Anguilliformes, which holds 1,000 species total. Although electric eels, spiny eels and cusk eels are not true eels, we have chosen to include them on this iceberg."

Entries reflect the chart authors' choices and are not verified fact.

"The Eel Iceberg" by u/PresentBluebird6022 (19 December 2025)

Tiers

Tiers and entries from the IcebergThreads version. Notes after a dash are shortened from the author's explanations.

Tier 1

• Eels are a Type of Fish – Ray-finned fish
• Lack of Pelvic Fins – Eels do not have pelvic fins
• Nocturnal – Most eels are nocturnal, meaning they are most active at night
• Leptocephalus – Eel larvae
• Eels as Food – A cuisine. 70% of eel catch goes to Japan
• Electric Eels Aren't True Eels – Are able to generate up to 860 Volts of electricity to stun prey. It is not a true eel
• Eels can Climb on Land – As long as their gills are moist, they can survive on land
• Moray Eels – A family of eels
• Freshwater Eels – Eels.... In fresh water.
• Carnivores – Eels are carnivores

Tier 2

• Largest Eel – Slender giant moray, at four meters
• Gymnothorax polyuranodon – Freshwater moray eel
• European conger – Heaviest true eel, up to 160kg
• Glass Eels – A stage in the development of eels
• Eels Have Two Sets of Jaws – The pharyngeal jaw is its second set
• Poor Eyesight – Eels have very poor eyesight
• Snake eels – Probably the most diverse family of Eels.
• Palauan primitive cave eel – Protanguilla. Most basal eel species.
• Ribbon eel – A vibrant species of moray eel
• Poor Hearing – Eels have poor hearing
• American Eels are Endangered – They are endangered in their habitats
• Shortfin and Longfin Eels – The two main eels of New Zealand

Tier 3

• Anguillavus – Extinct Basal marine eel from the Cretaceous
• Smallest Eel – Monognathus ahlstromi, at 5cm
• Deepest (True) Eel – Ilyophis robinsae, at 6,068m below the surface. Another group of fish, the cusk eels can survive up to 10,000m, but they are not true eels.
• Bean's sawtooth eel – Serrivomer beanii, a sawtooth eel described in 1883 that lives at depths between 0 and 5,998 meters.
• Brantevik Eel Lifespan – Up to 155 years in captivity
• Obstacle Climbing – The New Zealand longfin eel is known to climb dams and waterfalls of up to 20 meters.
• Chlopsidae – The False Moray Eels
• Saccopharyngiformes – Disputed order of eels, mostly considered advanced members of the true eel order, Anguilliformes
• Shrimp - Moray Symbiosis – Symbiosis between the cleaner shrimp and the moray eel
• Knot Tying – Moray eels tie themselves into knots
• Low Bone Density – Eels have lower bone densities, to aid with buoyancy
• Seasonal Migration – Has been recorded in yellow eels
• Courtship – Eels engage in courtship rituals before mating.

Tier 4

• Eels Can Swim Backwards – By reversing the wave they generate with their body.
• Anguilla australis x Anguilla anguilla – Artificial eel hybrid
• Pythonichthys arkansasensis – Extinct mud eel from the late Cretaceous
• Ciguatera poisoning – Moray eels often cause Ciguatera poisoning among those who eat it
• Saccopharynx ampullaceus – Rare deep sea eel species. They have a bioluminescent tip to their tail
• Cooperative Hunting – Groupers and Moray eels sometimes hunt together
• All American/European Eels Spawn in the Bermuda Triangle – All eels from America and Europe go to the Sargasso Sea to spawn
• Rice-paddy eel – Snake eel that lives in salt water, but spawns in fresh water.
• Regeneration – Eels have great regeneration capabilities
• Immune System – Currently not much is known about how it works and fights off pathogens
• Esophagus as an Osmoregulatory Organ – Eels use their esophaguses to regulate osmosis
• Magnetic Compass – European eels have a magnetic compass
• Sensory Receptors (Cusk Eels) – Cusk eels have sensory receptors in their fins to help detect fish on the ocean floor

Tier 5

• Mylomyrus – Extinct eels from the mid Eocene
• Giant leptocephalus – A deep sea eel. Its larval form is the biggest in the entire animal kingdom.
• Bakasi – Philippine delicacy of Richardson's moray (Gymnothorax richardsonii)
• Sexual dimorphism in morays – Many moray eel species have some sexual dimorphism in specifically the dentition (teeth). The ribbon eel is special since it has significant differences in coloration between sexes.
• Anarchias – Unique genus among the moray eels due to having four- rather than the normal three- supraorbital pores
• European Eels are Non-Panmictic – For a long time, it was thought that European eels mated together and at random, but studies show that they are not panmictic.
• Endurance – Study shows that in European eels, swimming 6,000km only uses 60% of their energy supply, leaving the remaining 40% for mating
• Eel Skin is a Tendon – The behaviour and mechanical properties of the skin of the American eel makes it seem that it is used as an external tendon
• Fluorescent Proteins in Morays – fluorescent fatty acid binding protein, the protein in eels, glows when it comes into contact with bilirubin. Scientists don't understand why eels have bilirubin.
• Deep sea origin of Freshwater eels – The freshwater eels of the family Anguillidae are nested within a clade of otherwise deep-water families. Particularly close relatives are known to spawn in the same layers of the ocean as freshwater…
• Remote Control (Electric Eels) – Electric eels have been observed to first send out a less-powerful electric shock, which "first stimulates prey to move and reveal itself", so that the electric eel knows where it is (they have poor…
• Parasitic eel – A species of Cutthroat eel that sometimes burrows inside other fish
• Brackish Adapting – Eels collected from brackish water can quickly adapted to freshwater life if needed
• Anguillavus mazeni – Extinct eel ancestor

Tier 6

• Granite moray – Undescribed species of western indian ocean species of snakemoray (genus Uropterygius)
• Lack of Premaxilla – Eels (except Protanguilla) lack Premaxilla. They are sometimes considered part of the Ethnovomer
• Freshwater vs Saltwater Growth – Studies found that anguillid eels grew over twice as fast in salt water than in freshwater. This is unknown in nature.
• Resorption of Blood – European eels dissolve their bones, to give the calcium to their blood supply, when they are migrating to mate.
• Feminisation of Japanese Eels – Soy isoflavones have been used to artificially feminise japanese eels for commercial purposes
• Taiwan – Most diverse place in terms of eel diversity
• Cave dwelling moray – Uropterygius cyamommatus. Inhabits anchialine caves (underground caves connected to the sea) and sometimes has the eye lost on the left side of the head.

See also

• Iceberg chart
• R/IcebergCharts
• Marine fish iceberg
• Deep-sea animals iceberg

Sources

• Featured Reddit chart: u/PresentBluebird6022. The Eel Iceberg. Reddit (r/IcebergCharts). 19 December 2025. Retrieved 29 October 2026.
• IcebergThreads version: FishIDK. Eel. IcebergThreads. 6 January 2026. Retrieved 29 October 2026.