The fan-bellied leatherjacket is a marine fish with a body strongly compressed from the sides and a long spine on its back. It lives in warm coastal waters among plants and can quickly change its coloration for camouflage.
The fan-bellied leatherjacket differs from related species by its fan-shaped ventral fin and its ability to change its body color very accurately. It helps maintain balance in coastal ecosystems by eating algae and small animals.
Immature form that undergoes metamorphosis before adulthood.
Worker
Dorsal spine count
birth time
bottom
Dogs, dolphins, lynx hang out for 9-25 years and party on their birthday three times a year
m
Map
will celebrate their {n} birthday
g
t
When your next jubilee falls in {name} life years
Human
days
How old you would be if you lived as {name}
Theoretical maximum lifespan estimated from the Dynamic Energy Budget (DEB) mathematical model. This value reflects a biological potential derived from metabolic parameters, not from direct observation — real recorded lifespans are often significantly shorter.
mollusks
adult
Maturity
plant
Pelvic fin color
About health
marine coastal
When your next birthday would fall if you lived as {name}
anemones
results
Southeast Asia and islands, always hot and humid
Colors
Sex
Upcoming jubilees
Gremllins
mo
all seas and oceans
Trophic type
Filters
Captures or processes food by biting or nipping with the mouth.
Upcoming birthdays
Truly long lives: 40-100 years. Bowhead whales, albatrosses, giant tortoises recall their birthday at most once a year
Lifespan
leaf
Age (from birth to death)
Foraging occurs on the floor of aquatic or terrestrial habitats.
Wanderers
Food items are collected from exposed outer surfaces of substrates.
algae
world of Australasia
Jubilee = every 10th birthday
Earliest developmental stage inside an egg or womb.
Business sausages
Lifespan average
Rapidly swallows prey or food items whole without chewing.
young after fast growth
Juvenile stage following larval metamorphosis but not yet adult.
What do they look like?
Maturity
emergence (insects)
end of lifespan
How do they live?
fertilization / egg laying
How do they behave?
birth / hatching
metamorphosis / end of larval stage
end of acceleration
Share
collecting and nibbling small objects from plants and bottom
live snails, mussels, oysters
Find a pet...
Mature, fully developed individual capable of reproduction.
gulping
Actively hunting and capturing live prey.
where the river flows into the sea, slightly salty water, lots of fish and birds
65 to 130 grams, 25 – 60 centimeters
Pets
Indomalayan realm
Dorsal spine size
Indomalayan realm
biting
Pelvic fin size
whole swallow
{name} jubilee
cm
Old-timers
Find an animal or breed...
turns
islands and part of Australia, many unusual animals and plants
Rascals
Pelvic fin count
Litter size
Map data sources: Ecosystem classification — IUCN Global Ecosystem Typology (Keith et al., 2022), indicative distribution maps Keith et al. (2020), https://doi.org/10.5281/zenodo.3546513; Large Marine Ecosystems — NOAA LME Program; Bathymetry — GEBCO Bathymetric Compilation Group (2026), GEBCO_2026 Grid, https://doi.org/10.5285/4f68d5c7-45eb-f999-e063-7086abc036fa; Climate data — Generated using Copernicus Climate Change Service information; Species occurrence data — GBIF.org, Derived dataset "all animals", https://zveriki.com/dataset/dataset.tsv; Terrestrial ecoregions — RESOLVE Ecoregions 2017 (Dinerstein et al., 2017), CC BY 4.0
How to care for them?
Living from 25 to 40 years. Orangutans, bald eagles, African elephants celebrate their birthday twice a year
grazing
°C
Not specified
Actively searching habitats to locate food items.
Where are they found?
all seas and oceans
Species lacks any fixed or lasting shelter structure.
Feeds by cropping or nibbling low-growing vegetation or algae.
Locomotion through water employed while searching for or capturing prey.
Legendary longevity: over 100 years. Galapagos tortoises, Greenland sharks, ocean quahogs celebrate with family once every 4 years
Offspring
Elders
Bro
Taxons
if born as {name}
omnivore
age
water is almost always warm, even in winter you can swim, very hot in summer
birth date
swimming
no permanent shelter
Close
was
Career from 7 to 15 months. Dwarf hamsters, voles, field crickets celebrate their birthday twice a month
Marine world
The basics
My weight?
Non-stop carnival: they only live a few days. Mayflies, rotifers, midges celebrate their birthday more than twice a day
surface
Dorsal spine color
primary food sources
Potential Habitat
d
In husbandry
On the go from 1.3 to 3.5 years. Forest mice, anoles, rainbow fish party on their birthday once a month
Feeding occurs in water bodies such as rivers, lakes, or oceans.
Mass
Mosquitoes, fruit flies, small crustaceans hustle for up to 7 months and throw a birthday party every week
Body size
islands and part of Australia, many unusual animals and plants
aquatic
Warm sea
{name} birthday
Food is gathered directly from leaf surfaces.
No results found
On the map
small crustaceans
all life stages
Female ♀
Body color
Map data sources: Ecosystem classification — IUCN Global Ecosystem Typology (Keith et al., 2022), indicative distribution maps Keith et al. (2020), https://doi.org/10.5281/zenodo.3546513; Large Marine Ecosystems — NOAA LME Program; Bathymetry — GEBCO Bathymetric Compilation Group (2026), GEBCO_2026 Grid, https://doi.org/10.5285/4f68d5c7-45eb-f999-e063-7086abc036fa; Climate data — Generated using Copernicus Climate Change Service information; Species occurrence data — GBIF.org, Derived dataset "all animals", https://zveriki.com/dataset/dataset.tsv; Terrestrial ecoregions — RESOLVE Ecoregions 2017 (Dinerstein et al., 2017), CC BY 4.0
Potential habitat modelled from GBIF occurrence data. Map © Zveriki.com, licensed under CC BY 4.0.
birth year
Maturity
Skin color
sq mm
yr
How similar?
Male ♂
until the celebration
age as {name}
How do they breed?
On the go from 3.5 to 6 years. Hedgehogs, crows, lizards treat themselves to birthday snacks 6 times a year
What if eaten?
Neither
from birth to adulthood
What do they eat?
Where do they live?
Immature individual that has not yet reached reproductive maturity.
Marine world
early young
River estuary into the sea
live sea anemones and corals
Duration
saline marine habitat
This is me
Gamers
aquatic plants and algae
How are they built?
marine
shallow near the shore, water rises and falls, crabs live here
mm
Theoretical lifespan
ml
Stars
Link copied
coastal marine zone — shelf, neritic zone
My age?
wk
My size?
Asexual
swap
Southeast Asia and islands, always hot and humid
active predation
Rabbits, falcons, red-eared turtles hang out for 6-9 years and party on their birthday four times a year
Where do they take shelter?
celebrated their {n} birthday
When you would have been born if you lived as {name}
Littoral Zone
Daddies
small crabs, amphipods and other crustaceans
Lifespan maximum
world of Australasia
foraging
Hermaphrodite ⚥
embryo
Carrot
Length
kg
Observations
◉{N} more on tap