What are Trigonotarbids?
Trigonotarbids are an extinct order of arachnids that are among the earliest land arthropods known. They emerged during the late Silurian, about 410 million years ago, and died out in the early Permian, about 300 million years ago. Trigonotarbids thrived during the Devonian and Carboniferous periods, when the land went from being entirely barren to covered in thick forests and swamps. About 380 million years ago, true spiders evolved, which they lived alongside until they went extinct for unknown reasons. Trigonotarbids are not the ancestors of spiders, but in fact a separate offshoot of Arachnida. Trigonotarbids obviously resemble spiders, to which they are closely related, though they aren’t the same. Trigonotarbids are more primitive all around. Instead of having a thin waist, like all true spiders, the head and body of these animals were fused together into a large box-like structure. Unlike spiders, which have a smooth body, trigonotarbids had a segmented body, reminiscent of a lo
