A species of African killifish has been discovered that reaches sexual maturity faster than any other vertebrate animal. Residing in temporary puddles, Nothobranchius kadleci starts to reproduce just 17 days after hatching.

Scientists from the Institute of Vertebrate Biology in the Academy of Sciences of the Czech Republic found some eggs reached hatching stage in 15 days, the shortest minimum generation time of any vertebrate.

Martin Reichard and institute colleagues studied the aging processes of two species of wild-caught fishes from southern Mozambique. In the wild, these fishes live in temporary pools that only occur during the rainy season when savannah depressions are filled with water.

"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," said Reichard. "If they mature very fast, they can produce a new generation."

The fish demonstrated rapid growth rates, with some specimens attaining nearly a quarter of their total body length per day. Rapid growth, early sexual maturation and quick reproductive cycles are common traits typical of extremophiles, organisms inhabiting temporary and unpredictable habitats.