More than four million centuries ago, when the first fish started to appear, the primordial waters were inhabited by 6-foot-long sea scorpions. The creatures resembled ancient Greek warships.
Pentecopterus, one of the earliest gigantic predators, lived during the age of fish. During that time, life was flourishing in the oceans rather on land. Pangea was the only continent in existence.
The creature was named after the Penteconter, a galley used by the ancient Greeks. While Penteconter had more than a dozen paddles, according to Britannica, the Pentecopeterus had more than a dozen legs. Both have long bodies.
One Sept. 1, the Colossal fossils of the marine beast were discovered in Northeastern Iowa. The remains were unearthed in an ancient meteorite impact crater more than 3 miles in diameter by the Upper Iowa River. The remains were excavated after the river was dammed temporarily.
Found in exceptionally good condition, the fine details of an adult and an infant's exoskeleton can be appreciated, Yahoo! News reported.
"Pentecopterus was an incredibly bizarre animal, with a long head that looked somewhat like the prow of a ship, a narrow body, and massively enlarged limbs that it used to capture prey," Yale University paleontologist James Lamsdell said.
"It would have grabbed prey with its large, spiny legs and then pulled it towards its mouth," Lamsdell added.
Pentecopterus is the earliest-known member of Eurypterids, an extinct arthropod group that was highly significant in the marine ecosystem of their time. Ranging from small scavengers to large apex predators, they are closely related to modern horseshoe crabs and terrestrial arachnids spiders and scorpions.
Eurypterids flourished until about 360 million years ago when their numbers dwindled drastically. They became extinct approximately 254 million years ago. The largest-known Eurypterids exceeded 8 feet long.
Older sea scorpions have been predicted to exist, and researchers are looking forward to discover them. Prior to the discovery of Pentecopterus, Brachyopterus was the oldest known member of the group. Pentecopterus is 10 million years older than the small, primitive eurypterid.
The research was published in the journal BMC Evolutionary Biology.
