Top and bottom--Part and counterpart of the same extinct spider-like arachnid--technically termed a Trigonotarbida arachnid (sort of a primitive spider that did not spin a web)--from the upper Pennsylvanian Lawrence Formation of the Douglas Group, Virgilian Stage--305 to 303 million years old. Called scientifically, Anthracomartus sp. Photographs courtesy a specific scientific publication. |