Potamarius nelsoni, or the Lacandon sea catfish, is a fish from the Ariidae family. It lives in freshwater rivers of southern Mexico and Guatemala and is distinguished by the male carrying the eggs in its mouth.
The Lacandon catfish differs from related species in its method of caring for offspring: the male holds the eggs and fry in its mouth. It is important for rivers because it feeds on detritus and small animals and serves as food for larger fish.
Finds food using whiskers and sucks it in with its mouth.
Legendary longevity: over 100 years. Galapagos tortoises, Greenland sharks, ocean quahogs celebrate with family once every 4 years
Immature form that undergoes metamorphosis before adulthood.
Offspring
Tropical moist forest
Worker
Elders
Bro
birth time
freshwater marsh and wetlands
Taxons
if born as {name}
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
riverbed
omnivore
g
age
t
When your next jubilee falls in {name} life years
Human
birth date
no permanent shelter
Close
very hot and very humid all year round, rain almost every day
detritus, eat dead remains of plants, animals and all kinds of organic debris on the bottom
was
days
Barbels count
South and Central America, hot and humid, huge forests
Career from 7 to 15 months. Dwarf hamsters, voles, field crickets celebrate their birthday twice a month
The basics
How old you would be if you lived as {name}
Neotropical realm
Venomous
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.
My weight?
Non-stop carnival: they only live a few days. Mayflies, rotifers, midges celebrate their birthday more than twice a day
whiskers
adult
Maturity
organic debris
fish of small size
primary food sources
Neotropical realm
South and Central America, hot and humid, huge forests
Coconut
live marine and freshwater shrimps
Potential Habitat
About health
When your next birthday would fall if you lived as {name}
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
Repro interval
results
Mass
Mosquitoes, fruit flies, small crustaceans hustle for up to 7 months and throw a birthday party every week
Colors
Sex
{name} birthday
Upcoming jubilees
Gremllins
mo
No results found
Trophic type
Filters
small fish
Yolk sac size
On the map
all life stages
Female ♀
Body color
always hot and humid, huge trees and vines
Upcoming birthdays
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.
Truly long lives: 40-100 years. Bowhead whales, albatrosses, giant tortoises recall their birthday at most once a year
Lifespan
birth year
Maturity
insect larvae and caterpillars
Age (from birth to death)
sq mm
yr
Wanderers
How similar?
Finds food using whiskers and sucks it in with its mouth.
Jubilee = every 10th birthday
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
Earliest developmental stage inside an egg or womb.
Business sausages
Lifespan average
What do they eat?
insect larvae
Where do they live?
Pectoral spines size
early young
What do they look like?
Maturity
water often floods the land, lots of grass
emergence (insects)
end of lifespan
Freshwater
How do they live?
fertilization / egg laying
Produces toxins capable of causing harm when delivered.
How do they behave?
birth / hatching
metamorphosis / end of larval stage
end of acceleration
Share
swampy freshwater biotopes — peat bogs, marshes, river mangroves
Duration
Find a pet...
Mature, fully developed individual capable of reproduction.
Freshwater
Always hot and wet
Egg count
This is me
freshwater
from 0.5 to 0.8 kilograms, 0.5 – 1 meter
Gamers
Pets
How are they built?
all rivers and lakes
Primary oral structure used to seize, manipulate, or ingest food.
mm
Theoretical lifespan
ml
Stars
Link copied
My age?
wk
My size?
lateral line
{name} jubilee
Asexual
swap
freshwater environment — rivers, lakes, ponds, swamps
cm
Old-timers
Find an animal or breed...
mouth
turns
Rabbits, falcons, red-eared turtles hang out for 6-9 years and party on their birthday four times a year
Rascals
Where do they take shelter?
Sensory system detecting water movements to locate prey.
Flooded grasslands
celebrated their {n} birthday
When you would have been born if you lived as {name}
Litter size
Daddies
Lifespan maximum
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?
Barbels size
Living from 25 to 40 years. Orangutans, bald eagles, African elephants celebrate their birthday twice a year
°C
Not specified
Hermaphrodite ⚥
Egg color
shrimp
Where are they found?
Species lacks any fixed or lasting shelter structure.
embryo
Dorsal fin size
all rivers and lakes
Length
kg
Observations
◉{N} more on tap