The discovery of a fossilized lamprey species, Mesomyzon mengae Chang, in Chengde, Hebei Province, China, marks a significant paleontological find. Identified by researcher Zhang Jiangyong from the Chinese Academy of Sciences, this extinct species has been dated back approximately 134 million years.

This particular discovery is noteworthy as it represents the first instance of Mesomyzon mengae Chang being found in Hebei Province. Previously, this species was known to have inhabited regions such as Inner Mongolia and the western part of Liaoning. The presence of the fossil in Fengning Manchu Autonomous County indicates a broader geographical distribution for Mesomyzon mengae Chang than previously thought.

Mesomyzon mengae Chang is particularly valuable to researchers due to its unique characteristics. Unlike many other fossils, this species lacks hard bones and scales, making its preservation rare and precious. It is considered one of the few jawless fossils known from the Mesozoic era, adding to its scientific significance.

Overall, this discovery provides valuable insights into the ancient biodiversity of the region and expands our understanding of the distribution and characteristics of Mesomyzon mengae Chang during the prehistoric period.