Gigantic Jurassic Creature Discovered Is Largest Of Its Species On Record

By Jeffrey Rapaport | Published

mysterious ocean

As reported by ScienceAlert, paleontologists unearthed an exciting discovery in Northern China: two fossilized lampreys dated to 160 million years ago, fossils revealing these exceedingly ancient fish evolved into formidable predators much earlier than thought.

Moreover, the fossils evidence that this ancient species vastly outsized its earlier evolutionary ancestors. Indeed, the discovery challenges assumptions concerning this enigmatic—and, let’s face it, terrifying—creatures, otherwise famed for both their longevity and relatively unaltered form across millions of years. 

Experts often refer to lampreys as “living fossils,” given their incredibly long evolutionary history. Their extant presence among Earth’s fauna began in the Paleozoic era, a short 360 million years ago. While modern incarnations of the fish may span up to a meter in length, their Paleozoic forebearers seem drastically smaller in comparison, measuring only a few centimeters long.

But the recently discovered Yanliaomyzon occisor, as scientists dubbed the new find, stretches over 64 centimeters, implying a significant leap in size. To date, it amounts to the largest fossilized lamprey. 

Paleontologists dug up the exciting discovery in Yanliao Biota, Northern China, an area famed for its uniquely well-preserved Lagerstätte fossils. Such finds remain invaluable in charting the evolutionary history and origins of lampreys. Feixiang Wu of the Chinese Academy of Sciences led the research team, featuring colleagues Chi Zhang and Philippe Janvier; the crew employed X-ray micro-computerized tomography to thoroughly scan and visualize the fossils three-dimensionally. 

sea lamprey

Along with hagfish—another species straight out of a horror movie—lampreys belong to the peerlessly scary category of jawless vertebrates (eels, often likened to both the former and the latter, do not). Their feeding method, characterized by a circular, toothed mouths latching onto and draining the blood from other fish, is a little unsettling, to say the least.

For its part, the Yanliaomyzon occisor exhibited a fiercer and more muscular biting ability, indicating a carnivorous diet. The Jurassic period represented a significant shift in their feeding tendencies and, ultimately, physical form.

It’s difficult to overstate the scientific importance of the North Chinese discovery, which provides enormous insights into the evolutionary story of lampreys, especially concerning their feeding anatomy. While earlier fossils demonstrate weak feeding structures, incapable of predation and implying a diet of algal mats, the evidence from the Yanliaomyzon occisor points to a carniverous diet. The further findings of fish bones and skeletal remains inside the intestinal tracts of the fossilized fish only confirm this theory. 

Ultimately, the discoveries from this research illuminate not only the life and habits of these oversized Jurassic lampreys but also offer implications surrounding their place of origin. Defying previous assumptions, the discovery hints at a Southern Hemisphere origin of the fish. 

Additionally, the more scientists understand the size and diet of the creatures, the more they unravel the ecological dynamics of the Jurassic era as a whole. Generally, the lamprey’s large body frame correlates with enhanced biological capabilities—longer migratory distances, increased egg production, and more robust adaptation to varying water salinities. Such abilities, in turn, paint a picture of the wider, ancient ecosystem the fish inhabited. 

Beyond adding a new chapter to the narrative of vertebrates, the findings underscore the complexity and diversity of lifeforms gracing our planet–whether in the past, present, or future.