JURASSIC DINOSAUR FAUNAS IN ZIGONG - 自贡恐龙博物馆

Cetiosauridae gen. et sp. indet.
Material Twelve caudals in the middle and posterior portion of the tail. ZDM 0115.
Locality and horizon Liangshuijing, Zigong; Daanzhai Member of Ziliujing Formation,
Early Jurassic.
Middle Jurassic Sauropoda-Shunosaurus Fauna
The Sauropoda-Shunosaurus Fauna mainly contains sauropods, carnosaurs, ornithopods and
stegosaurs of dinosaurs. Other vertebrates include fishes, labyrinthodont amphibians, turtles,
crocodiles, plesiosaurs, pterosaurs, and mammal-like reptiles. They distributed in the Xintiangou
and Xiashaximiao formations. The Dashanpu Dinosaur Quarry is the most typical locality of this
fauna.
Class Chondrichthyes
Subclass Elasmobracnchii
Order Selachii
Family Hybodontidae Owen, 1846
Genus Hybodus Agassiz, 1837
Diagnosis Medium-sized hybodontid characterized by spindle-shaped body; anterior
dorsal fin positioned between pectoral and pelvic fins, and posterior dorsal fin anterior to anal fin;
conical, sharp and straight teeth with a main cusp and one or more inferior cusps on both side;
teeth on anterior margin of stout fewer but larger; hard spine of dorsal fin with longitudinal ridges
and grooves, and posterior edge of hard spine with two rows of tooth-like processes; anal fin
lacking hard spine; and heterocercal fins.
Hybodus zigongensis sp. nov.
Diagnosis Medium-sized hybodont recognized by lower and enameled tooth crown with
obvious ∧-shaped striations coming from base of crown and joining together at tip; slightly
retreated tip of main cusp; only one inferior cusp anterior or posterior to main cusp; main cusp
about half width of tooth; and inferior cusps connect to main cusp at base of crown.
Holotype A nearly complete tooth. ZDM 1004-a.
Paratype An incomplete tooth. ZDM 1004-b.
Referred material Seven incomplete teeth. ZDM 1004-c, ZDM 1004-d, ZDM 1004-e,
ZDM 1004-f, ZDM 1004-g, ZDM 1004-h and ZDM 1004-i.
Locality and horizon Dashanpu, Zigong; Xiashaximiao Formation, Middle Jurassic.
Etymology Specific name refers to Zigong where the specimens were unearthed.
Hybodus huangnidanensis Wang, 1977
Diagnosis Tooth relatively large with moderate height; tooth crown with straight ∧