Threatened arthropods and described. The total number of living arthropod species is probably in the tens of millions. One conservative estimate puts the number of arthropod species in tropical forests alone at six to nine million species. As a consequence of all of the above, most published estimates of the total number of endangered insects and arachnids are probably low by at least an order of magnitude. Conservatively at least eighty percent of all living animal species are arthropods. Since arthropods constitute the majority of the faunal biomass on Earth, their role is vital to the survival of large numbers of insectivores
Tarantula silken "tube tent", terrestrial species line their burrows with silk to stabilize the burrow wall and facilitate climbing up and down. Tarantulas mainly eat large insects and other arthropods such as centipedes, millipedes, and other spiders, using ambush as their primary method of prey capture. Armed with their massive, powerful chelicerae tipped with long chitinous fangs, tarantulas are well-adapted to killing other large arthropods. The biggest tarantulas sometimes kill and consume small vertebrates such as lizards, mice, bats, birds, and small snakes. The eight legs, the two chelicerae with their fangs, and the pedipalps are attached to the prosoma. The