It is placed in the extinct order Uraraneida,[1] spider-like animals able to produce silk, but which lacked true spinnerets and retained a segmented abdomen bearing a flagellum-like tail resembling that of a whip scorpion.

[citation needed] An important Early Devonian (about 390 million years ago) fossil example from Gilboa, New York, was originally described as a member of the extinct order Trigonotarbida and named Gelasinotarbus?

[3] It was later assigned to a new genus Attercopus[4] and reinterpreted as the oldest, and most primitive, example of a true spider and described as being the first user of silk in animals.(Araneae).

This hypothesis was based on the supposed presence of unique spider features such as silk-producing spinnerets and the opening of a venom gland on the fang of the chelicera.

Further study – based on new fossils from a comparable Devonian locality called South Mountain – and comparison with other material from the Permian of Russia, i.e., of Permarachne, indicates that Attercopus does not actually have spinnerets.