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
Pauropoda Pauropoda Pauropods are small, pale, millipede-like arthropods. Around 830 species in twelve families are found worldwide, living in soil and leaf mould. They look rather like centipedes, but are probably the sister group to millipedes. The name is derived from the Greek roots ' "few" and ' "foot". Pauropods are soft, cylindrical animals with bodies long. The first instar has three pairs of legs, but that number increases with each moult so that adult species may have nine to eleven pairs of legs. They have neither eyes nor hearts, although they do have sensory organs which can detect light. The