Killifish is fastest grower in the world

An African killifish is believed to be the fastest growing vertebrate animal in the world.

It’s a real case of “grow fast die young” for the Nothobranchius kadleci killifish which can be reproducing just 17 days after hatching.

Some eggs reach hatching stage in 15 days meaning they also have the shortest minimum generation time in vertebrates.

Dr Martin Reichard and colleagues from the Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic studied two species of wild-caught fishes from southern Mozambique under laboratory conditions.

In the wild, these fishes live in extreme conditions of temporary pools that only occur during the rainy season when savannah depressions are filled with water.

Because the fish live in such temporary accommodation, it is vital for their survival that they mature quickly.

Dr Reichard said: “I’m pretty sure if conditions are good, they would be able to sexually mature even faster in the wild. It is biologically very relevant for these fish to be able to sexually mature very fast because their habitat may dry out in three to four weeks. If they mature very fast, they can produce a new generation.

“If conditions are inferior – food is less abundant, there is a high density of fish – it would take them longer but they can still complete their lifecycle.”

Other species of killifish are a popular aquarium pet. They can be fed smaller foods such as Nutrafin Max Tropical Colour Flakes.

The fish have to time their mating so that the next generation can remain in the soil as dormant eggs and embryos in the dry season and then flourish when the next rains come.

The killifish may be the quickest growing vertebrate but they are not the shortest living. That honour goes to the pygmy goby which only lives an average of 59 days. The coral reef pygmy goby (Eviota sigillata) claimed that prize from the previous incumbent which was the turquoise killifish (Nothobranchius furzeri), which like its cousins, inhabits seasonal rain pools in Africa and must complete its life cycle before the pools disappear.

Add your comment

* Required fields