Turquoise killifish

Nothobranchius furzeri is a small (4–6 cm) annual killifish (family Nothobranchiidae) native to seasonal pools in the semi-arid lowlands of southeastern Africa (Mozambique and Zimbabwe). It has the shortest lifespan of any vertebrate that can be raised in captivity—some strains live only 4–6 months—making it an increasingly important model organism for aging research. Males are strikingly colorful with a bright turquoise-blue body, red-orange caudal and anal fins, and variable patterning; females are cryptically colored in dull brown. In the wild, populations inhabit ephemeral rain pools that completely dry out within months. Adults mature rapidly (as early as 2–3 weeks), spawn prolifically, and die when pools desiccate. Eggs survive the dry season in diapause states within the mud, capable of arresting development at multiple stages for months or even years until rains return. This annual life history is an adaptation to unpredictable African savanna habitats. N. furzeri shows typical vertebrate aging phenotypes (cognitive decline, cancer, sarcopenia, reduced regeneration) in a compressed timeframe, enabling high-throughput aging studies. Its genome has been sequenced, revealing genes associated with lifespan variation. It is also used in studies of diapause, circadian rhythms, gut microbiome–aging interactions, and regenerative biology.