Phylum Chordata | Class Hyperoartia Order Lamprey | |
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Genus MesomyzonChang, Zhang & Miao 2006 Similar Lamprey, Priscomyzon, Mayomyzon, Tetrapleurodon, Greek lamprey | ||
Mesomyzon mengae is an extinct lamprey from freshwater strata of the Early Cretaceous-aged Yixian Formation, in China. So far, M. mengae is the only lamprey, and by default, the only agnathan known from post-Paleozoic fossils.
The animal's exquisitely preserved fossils show a creature very similar to modern-day lampreys, having a well-developed sucking oral disk, a branchial basket, at least seven pairs of gill pouches and corresponding gill arches, impressions of gill filaments, and at least 80 myomeres of its musculature.
References
Mesomyzon Wikipedia(Text) CC BY-SA