This infraorder of the suborder Aranae includes the families of living 8-legged creatures (over 3000 species) like trapdoor spiders and of course tarantulas. The forward and parallel chelicerae (orthognath) are typical. Unlike the Araneomorphae, they do not have more developed appearances such as cross-acting fangs or a silk spinning organ called cribellum. They differ from the Mesothelae in the lack of abdominal segmentation, and the number of spinnerets is also reduced (usually only two pairs). Depending on the genus, the animals of this infraorder can reach an old age of well over 20 years. However, this only affects the female animals, males usually die much earlier. Depending on their origin, tarantulas are divided into old world tarantulas (from Asia, Australia, Africa, "Europe") and new world tarantulas (South, Central and North America).