Megarachne servinei
|
Megarachne servinei Temporal range: Gzhelian |
|
|---|---|
 |
|
| Fossil of Megarachne servinei exhibited at the Museu de Ciències Naturals de Barcelona | |
 |
|
| Reconstruction of Megarachne servinei | |
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Subphylum: | Chelicerata |
| Class: | Merostomata |
| Order: | †Eurypterida |
| Family: | †Mycteroptidae |
| Genus: |
†Megarachne Hünicken, 1980 |
| Species: | †M. servinei |
| Binomial name | |
|
Megarachne servinei Hünicken, 1980 |
|
Megarachne servinei is an extinct eurypterid found in Upper Carboniferous (Pennsylvanian Gzhelian)-aged freshwater strata in San Luis, Argentina.
Megarachne servinei was originally described in 1980 by the Argentinean palaeontologist Mario Hünicken. The holotype was recovered from the Pallero Member of the Bajo de Véliz Formation of Argentina, a locality dated to the Asselian Age (298.9 to 295 million years ago (Ma)). Hünicken wrongly identified the specimen as a mygalomorph spider based on the shape of the carapace, the 15 millimetres (0.59 in) wide circular eye tubercle located between the two eyes in the center of the head, a structure in front of the carapace he identified as spatulate chelicerae, and a circular structure behind the first body segment which he identified as the "moderately hairy" abdomen. Hünicken's identification relied heavily on X-ray microtomography of the holotype, and additional hidden structures were also extrapolated from the X-radiographs.
With a legspan estimated to be 50 centimetres (20 in), this would have made Megarachne servinei the largest spider to have ever existed, far exceeding the goliath birdeater (Theraphosa blondi) which has a maximum legspan of only around 30 centimetres (12 in). The discovery quickly became popular and various exhibits with reconstructions of Megarachne servinei as a gigantic spider were set up in museums around the world.
The identification of the specimen as a spider was doubted by some arachnologists. Even Hünicken himself acknowledged discrepancies in the morphology of the fossil that could not be accommodated with an arachnid identity. However, the holotype was by then deposited in a bank vault and other paleontologists had access only to the plaster casts.
...
Wikipedia