Phonetic: Yee-kel-op-teh-rus, sometimes pronounced as Jee-kel-op-teh-rus.
Named By: Waterston - 1964.
Synonyms: Pterygotus howelli, Pterygotus rhenaniae
Classification: Arthropoda, Merostomata, Eurypterida, Pterygotidae.
Species: J. rhenaniae (type), J. howelli.
Size: Estimated about 2.5 meters long from the head to the tip of the telson (end of the tail)
Known locations: Germany - Klerf Formation.
Time period: Emsian of the Devonian.
Fossil representation: Single chelicerae.
after Otto Jeakel, Jaekelopterus is currently the
largest known eurypterid,
even bigger than the more famous Pterygotus.
demonstrates how the arthropods grew to giant proportions which
continue to remain unknown in today’s living arthropods.
Jaekelopterus itself it thought to have been a
freshwater species that
possibly hunted other arthropods and possibly fish.
The upper size estimate of Jaekelopterus was extrapolated by comparing the size of the chelicerae to other more complete specimens and then scaling up the size of the compared specimens to reveal the size. The problem with this method is that it is only as reliable as the similarity between the compared specimens, and caution needs to be exercised when using it. This caution was also reflected by the authors of the discovery, Simon Braddy and Markus Poschmann, who estimated the length of Jaekelopterus at 2.5 meters, even though comparison scaled it closer to 2.6 meters in length.
- Giant claw reveals the largest ever arthropod. - Biology Letters 4 (1): 106–109 - Simon J Braddy, Markus Poschmann & O. Erik Tetlie - 2007.
- Reply: giant claws and big bodies. - Biology Letters. 4 (3): 281. - Simon J. Braddy & Markus Poschmann & Erik Tetlie - 2008.
- An isolated pterygotid ramus (Chelicerata: Eurypterida) from the Devonian Beartooth Butte Formation, Wyoming. - Journal of Paleontology Volume 84, Issue 6, pp1206-1208. - Kames C. Lamsdell & David A. Legg - 2010.