Aphonopelma seemanni (the Costa Rican zebra knee tarantula) is also known as the Striped-knee tarantula. This spider has bold alabaster striping on its patella ("knees") which strongly contrasts against its chestnut colored legs and body. The zebra knee's underside is notably fuzzier than its top and has a conspicuous fawn coloration, as does its spinnerets (silk-spinning organs).
   Some individuals have a faint blue hue to their hairs throughout the juvenile stage; some only hold this hue for a short time after molting. When males mature, they often lose much of their striping and evince a deep purple luster, especially on their femora.
   These spiders are terrestrial burrowers, endemic to scrublands in Costa Rica through Guatemala. Aphonopelma seemanni grow to be a moderate size of about 5 inches. Female Costa Rican zebra knee tarantulas can live to be 15-20 years. Males are much shorter lived.