Mesomyzon mengae Chang, Zhang & Miao, 2006
Early Cretaceous (Berriasian)
Yixian Formation
Ningcheng, China

Large and extraordinary specimen of a Cretaceous lamprey. 267mm (10.5 inch) lamprey on 368mm (14.5 inch) slab. Extremely rare. You just never see these animals as fossils.

Lampreys are bizarre primitive parasitic agnathans that feed on the blood and fluids of living fish. Their bizarre, sucker-like mouth gives them an almost monstrous appearance. Their internal skeleton is made of cartilage so they are almost never found as fossils. Oddly, nearly all known fossils of lampreys are from the Paleozoic with none are known at all from the Cenozoic, even though they do exist in modern oceans and lakes. This Cretaceous specimen is one of the youngest known fossil lampreys and is the first we have ever seen.

See: Wikipedia – Lamprey

The fossil species shown here is described in: Chang, Mm., Zhang, J. & Miao, D. A lamprey from the Cretaceous Jehol biota of China. Nature 441, 972–974 (2006). https://doi.org/10.1038/nature04730