(finned one or wing animal).
Named By: Louis Agassiz
Classification: Arthropoda, Merostomata, Eurypterida, Pterygotioidea, Pterygotidae.
Species: P. anglicus (type), P. arcuatus, P. barrandei , P. bolivianus, P. carmani, P. cobbi, P. denticulatus, P. floridanus, P. gaspesiensis, P. kopaninensis, P. lanarkensis, P. lightbodyi, P. ludensis, P. marylandicus, P. monroensis.
Size: Body of large individuals up to 1.75 meters long, though there is considerable variation between species.
Known locations: Mostly Silurian deposits in Europe, especially the British Isles and Devonian deposits in North America. Some specimens have also been recovered from other parts of the world that have marine deposits dating back to these time periods.
Time period: Silurian to mid Devonian.
Fossil representation: Several specimens known.
largest known eurypterid,
Pterygotus remains have
been recovered from
the world over suggesting that it was a highly successful predator.
Pterygotus had four compound eyes with two smaller
ones on top of the
head and two larger ones at the front. This would have given Pterygotus
exceptionally good vision for its time with a potentially good degree
of depth perception as can be seen in jumping spiders today.
Pterygotus could use its paddle like appendages for swimming but could also move its tail for propulsion, perhaps to provide an extra burst of speed when attacking prey. It probably would have focused its attention on other arthropods such as trilobites which would have been very common at the time.
Numerous species have been attributed to Pterygotus, but some have been questioned. The above species mentioned are generally accepted, but may not feature all.
- Merostomata. Part P Arthropoda 2, Chelicerata. Treatise on Invertebrate Paleontology. pp. 30–31. - Leif Stromer - 1955.
- Pterygotus anglicus Agassiz (Chelicerata: Eurypterida) from Atholville, Lower Devonian Campbellton Formation, New Brunswick, Canada. - Palaeontology 50 (4): 981–999. - Randall F. Miller - 2007.
- All the better to see you with: eyes and claws reveal the evolution of divergent ecological roles in giant pterygotid eurypterids". Biology Letters. 11 (8). - Victoria E. McCoy, James C. Lamsdell, Markus Poschmann, Ross P. Anderson & Derek E. G. Briggs - 2015.