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The order of Acipenseriformes (Sturgeon-like fishes) both includes sturgeons (Acipenseridae) and paddlefish (Polyodontidae). At least three Sturgeon-like fishes (Acipenseriformes) can be found in the Jiufotang Formation (Jehol Group) and in the Yixian Formation in western Liaoning and northern Hebei Province China: Peipiaosteus pani Liu and Zhou, 1965, Protopsephurus liui Lu, 1994 and Yanosteus longidorsalis Jin, Tian, Yang & Deng, 1995. The Jiufotang Formation - where Peipiaosteus comes from - is dated to about 120.3+/-0.7 million years ago, which was during the Aptian age of the Cretaceous; the Yixian Formation - where Protopsephurus liui and this Y. longidorsalis can be found - is dated slightly older, around 125-121 million years ago (Barremian-early Aptian). Diagnosis from Hilton et al 2021, p. 2: "A †peipiaosteid (sensu Grande and Bemis, 1996) that differs from all other members of the family by possessing an extremely elongate dorsal fin. Other characters that, in combination, differentially diagnose †Yanosteus from other Acipenseriformes include short, stout pectoral fin spine, supraorbital sensory canal anterior to frontal surrounded by a series of small bony tubes, and the absence of epaxial caudal-fin rays." Line drawing from Jin et al. 1995: Identified by oilshale using Jin et al. 1995. References: Jin Fan, Tian Yanping, Yang Youshi, Deng Shaoying (1995) An early fossil sturgeon (Acipenseriformes, Peipiaosteidae) from Fengning of Hebei, China. Vertebrata PalAsiatica, Vol 33, Issue 1, pp. 1-16. Hilton, E., Grande, L., & Jin, F. (2021) Redescription of †Yanosteus longidorsalis Jin et al., (Chondrostei, Acipenseriformes, †Peipiaosteidae) from the Early Cretaceous of China. Journal of Paleontology, 95(1), 170-183. doi:10.1017/jpa.2020.80