Megarachne servinei, the only species belonging to the genus Megarachne, was an Upper Carboniferous (Pennsylvanian) eurypterid found near Córdoba, Argentina. It was originally described as a spider with a body length of 339 millimetres (13.3 in), which would have made it the largest spider ever to have existed. In 2005, the fossil specimen was reexamined and determined to be a small eurypterid within the family Mycteroptidae rather than a spider.

 Надо сказать, что мегарахну сперва считали гигантским пауком, наподобие гигантских карбоновых скорпионов, насекомых и многоножек, поэтому большая часть реконструкций ошибочна.

 Репродукции (1, 2):

 Неправильные реконструкции:

 Ископаемые останки (1, 2, 3):