The Mexican redknee tarantula (Brachypelma smithi) is a species of terrestrial tarantula native to Mexico, but might be found in small numbers in neighboring countries. They are among the most popular tarantulas available in the pet trade, due to their impressive size and striking coloration. An adult female has a body roughly 10 cm (4 in) long, with a legspan of 15-18 cm (6-7 in), and a weight of approximately 15-16 g (0.7 oz).Photo credit: Fir0002