A couple of fossil scorpions, e.g., Brontoscorpio , may have been as much as 1 meter in length. This is only an estimate though, because complete specimens of these large scorpions have never been found. The largest nearly-complete scorpion fossils known measure about 40 cm in length. There are several very small species, but the smallest may be Microtityus waeringi , the smallest of which measures a scant 12 mm when fully grown. One of the smallest scorpions in the United States is Vaejovis waueri , which reaches a length of 23 mm.
Scorpions are unusual among arachnids in having life spans that last more than one season.
Their longevity is affected by several factors. Among them are temperature, food availability, stress, predation, etc. Scorpions in tropical areas tend to develop faster than similar scorpions in more temperate areas. Most scorpions develop to maturity in 1 to 3 years and live 1 to 3 years as adults for a total lifespan of from 2 to 6 years. The shortest lifespan reported for a scorpion is just under two years.