Megarachne servinei, live reconstruction

  • Megarachne servinei

Megarachne ( gr μέγας mégas " large" and ἀράχνη Arachne "spider" ) was considered the largest spider that has ever lived. Since the fossil has features not found in other spider species, belonging, however, was strongly doubted the spinning of many scientists. Stand firm now seems that Megarachne not one of the spiders, but to the now-extinct Eurypteriden, ie to the lake or giant scorpions. Only the type species Megarachne servinei has been scientifically described.

Description and taxonomic re-evaluation

Megarachne servinei lived in the Carboniferous and had a body length of 34 cm. The span of the legs was more than 50 cm, there are also details of 60 cm and even 70 cm.

The Megarachne unlike any spider today, which is why they - as it now turns out wrong - filed into its own family of spiders ( Megarachnidae ). The classification was made as the shape of their carapace, the design of its mouthparts of its round belly (?) And 15 mm wide, circular eye which lies between the other two eyes in the middle of the head because of characteristics. They can describe to moderately hairy easy.

Only more extensive analyzes that were conducted at the University of Manchester by Paul Selden and his colleagues showed that Megarachne attributable to the lake or giant scorpions ( Eurypteriden ). The researchers stood for their studies in addition to the existing copy of 1980, while still a recent discovery piece available so that further important insights were gained on the taxonomy.

Habitat and time

Megarachne servinei lived 200 million years before the dinosaurs in the Upper Carboniferous, which was crucial for the size. In the carbon -dominated huge rainforests earth (see: coal), which caused an enormous oxygen content of the atmosphere. As arachnids and insects require much oxygen for growth, this was the perfect time; Today, the animal would suffocate. Only the giant dragonfly Meganeura could keep up with the size, so they had little enemies (vertebrates were not developed enough ).


In 1980, Prof. Dr. Hünicken discovered in the upper carbon layer in the Argentine province of San Luis, the giant animal. This was the first discovery of Megarachne servinei. Meanwhile, another fossil specimen has emerged, which was also discovered in Argentina.

The " largest spider of all time"

With the departure of Megarachne was a tarantula Theraphosa blondi whose leg span is about 30 inches until 2001 as the largest spider in the world.

However, the Lao True Spiders Heteropoda maxima exceeds the dimensions of T. blondi. The found in 1939 in Southeast Asia and described H. 2001 maxima has a leg span of 35 centimeters.