United States Fish and Wildlife Service list of threatened and endangered arthropods species may be treated as endangered or threatened if it resembles in appearance a species which has been listed and enforcement personnel would have difficulty distinguishing between the listed and the unlisted species; if the effect of this difficulty is an additional threat to the listed species; and if such treatment of the unlisted species would improve protection for the listed species. United States Fish and Wildlife Service list of threatened and endangered arthropods List of threatened and endangered arthropods, including insects, arachnids, and crustaceans under the United States Endangered Species Act as of October 2013. Key to Listing Status
Threatened arthropods millions of undocumented arthropods on Earth. Arthropods as a group have been very successful organisms on this planet, comprising over half of all the higher life forms. However the expanding human population has led to demise of many arthropod species through the mechanisms of deforestation, conventional farming, slash-and-burn methods in the tropics, habitat fragmentation via urban development, excessive use of pesticides and even the success of forest fire suppression. The social/political practice whereby a species is given a formal designation as "Endangered" or "Protected" is a different matter, called "Conservation status", and discussed elsewhere; see Endangered Species List for the