Petitella bleheri, or red-headed tetra, is a small schooling fish up to four centimeters long. It lives in rivers of the Amazon basin and is immediately noticeable due to its bright red front part of the head.
The red-headed tetra differs from other tetras with its bright red head and black spot at the tail. It serves as food for larger fish and helps control the population of small invertebrates in the Amazon rivers.
tetra granules
Immature form that undergoes metamorphosis before adulthood.
Worker
birth time
Dogs, dolphins, lynx hang out for 9-25 years and party on their birthday three times a year
daphnia
m
Map
will celebrate their {n} birthday
corethra
g
t
When your next jubilee falls in {name} life years
Human
Litters lifetime count
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
days
South and Central America, hot and humid, huge forests
How old you would be if you lived as {name}
crustaceans
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.
small planktonic crustaceans — copepods, krill
adult
Maturity
organic debris
plant
South and Central America, hot and humid, huge forests
About health
live tubifex
When your next birthday would fall if you lived as {name}
Repro interval
results
temperature for housing
rotifers
Colors
Sex
Upcoming jubilees
Gremllins
mo
nh₃
Trophic type
Filters
age diag byOther
always hot and humid, huge trees and vines
Upcoming birthdays
Truly long lives: 40-100 years. Bowhead whales, albatrosses, giant tortoises recall their birthday at most once a year
Lifespan
leaf
Desert and dry shrubs
most of Europe and Asia, various forests, steppes and tundra
bloodworm
Wanderers
Food items are collected from exposed outer surfaces of substrates.
algae
Jubilee = every 10th birthday
Minimum space
cereal mixes
Earliest developmental stage inside an egg or womb.
Business sausages
Lifespan average
artemia nauplii
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
swampy freshwater biotopes — peat bogs, marshes, river mangroves
dry food
Carbohydrates
Find a pet...
Mature, fully developed individual capable of reproduction.
Freshwater
hot, uneven rains, lots of grass and trees
copper excess
Actively hunting and capturing live prey.
Pets
all rivers and lakes
Primary oral structure used to seize, manipulate, or ingest food.
tobacco smoke and nicotine
training aptitude
{name} jubilee
cm
Old-timers
Find an animal or breed...
mouth
turns
small cyclops
Rascals
Flooded grasslands
Fat
hot Africa south of the desert, many savannas and forests
Litter size
Tropical savanna
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
°C
Not specified
Actively searching habitats to locate food items.
Egg color
Where are they found?
Species lacks any fixed or lasting shelter structure.
all rivers and lakes
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
Tropical moist forest
Elders
Bro
freshwater marsh and wetlands
Taxons
if born as {name}
omnivore
age
birth date
Protein
Palearctic realm
swimming
no permanent shelter
Close
water column
was
Career from 7 to 15 months. Dwarf hamsters, voles, field crickets celebrate their birthday twice a month
The basics
Neotropical realm
My weight?
bakery products
Non-stop carnival: they only live a few days. Mayflies, rotifers, midges celebrate their birthday more than twice a day
young after transformation
surface
3 to 8 grams, 0.5 – 5 centimeters
primary food sources
Neotropical realm
Potential Habitat
dry tetra food
Water
d
In husbandry
Feeds while suspended in open water between surface and bottom.
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
Gestation
aquatic
age diag byColoration
{name} birthday
Food is gathered directly from leaf surfaces.
age diag bySize
No results found
On the map
lunge
frozen bloodworms large quantities
all life stages
Female ♀
Body color
Body temperature
copper and compounds
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.
spirulina
birth year
Maturity
Calcium + Vitamin D3
sq mm
yr
How similar?
Egg size
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?
sessile ciliates
Neither
from birth to adulthood
What do they eat?
Where do they live?
Immature individual that has not yet reached reproductive maturity.
artemia
beef
early young
water often floods the land, lots of grass
world of Afrotropics
Freshwater
small insects
Duration
Vitamin C
Fins color
Always hot and wet
This is me
freshwater
Gamers
aquatic plants and algae
How are they built?
small insects without further specification
mm
Theoretical lifespan
ml
Stars
Link copied
My age?
wk
My size?
temperament
Asexual
swap
freshwater environment — rivers, lakes, ponds, swamps
Iodine
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?
Head color
celebrated their {n} birthday
When you would have been born if you lived as {name}
Daddies
Lifespan maximum
micro worms
foraging
Berry
whole life
small earthworms
Hermaphrodite ⚥
garlic
embryo
flake feed
Length
kg
very hot and dry, rare rains, cacti live
Rapid forward strike to seize prey.
Observations
◉{N} more on tap