Pronunciation: JOO-chang-TIE-tuhn
Meaning: Zhucheng giant
Author/s: Mo et al. (2017)
Synonyms: None known
First Discovery: Shandong, China
Acta Ordinal: #975
Zhuchengtitan zangjiazhuangensis
Zhuchengtitan comes from one of the most fossil-rich regions on Earth, the Late Cretaceous Wangshi Group of Zhucheng in Shandong Province—a place whose faunal assemblage rivals that of anywhere in Late Cretaceous North America. The quarries here have yielded thousands of fossils, from the giant hadrosaur Shantungosaurus to the tyrannosaurid Zhuchengtyrannus, the ceratopsian Sinoceratops, a possible ankylosaur in Sinankylosaurus, and a wider community that includes leptoceratopsids, lambeosaurines, small neornithischians, oviraptorosaurs, and broad fields of dinosaur eggs. So prolific is this landscape that six dinosaurs now honour Zhucheng in their names.
Yet despite this extraordinary abundance, Zhuchengtitan is known from only a single fossil: a solitary right upper arm bone—the humerus—recovered in 2008 from a quarry at Zangjiazhuang village, positioned at the boundary between the Xingezhuang and Hongtuya formations. Its discovery marks the first titanosaurian sauropod ever reported from Shandong's Late Cretaceous strata.
The humerus is strikingly broad at its top end, flaring to a width equivalent to 55% of the bone's total length—an extreme proportion that implies a substantial shoulder girdle. Along its upper surface runs a prominent deltopectoral crest, a long ridge where the major shoulder and chest muscles—the deltoids (musculus deltoideus) and pectorals (musculus pectoralis)—attached. These muscles lifted and repositioned the forelimb during the recovery phase, and—more importantly—pulled the limb forward during the power stroke, then braced it as the animal's weight moved over the planted foot. Even from a single bone, Zhuchengtitan reveals a forelimb built for strength, supporting a large titanosaur moving among the braided rivers, mudflats, and floodplains of Zhucheng.
The humerus is strikingly broad at its top end, flaring to a width equivalent to 55% of the bone's total length—an extreme proportion that implies a substantial shoulder girdle. Along its upper surface runs a prominent deltopectoral crest, a long ridge where the major shoulder and chest muscles—the deltoids (musculus deltoideus) and pectorals (musculus pectoralis)—attached. These muscles lifted and repositioned the forelimb during the recovery phase, and—more importantly—pulled the limb forward during the power stroke, then braced it as the animal's weight moved over the planted foot. Even from a single bone, Zhuchengtitan reveals a forelimb built for strength, supporting a large titanosaur moving among the braided rivers, mudflats, and floodplains of Zhucheng.
(Zhucheng Giant from Zangjiazhuang)Etymology
Zhuchengtitan is derived from "Zhucheng" (for Zhucheng City) and the Greek "titan" (a giant pre-Olympian deity from Greek mythology).
The species epithet, zangjiazhuangensis, means "from Zangjiazhuang" in Latin.
Discovery
The remains of Zhuchengtitan were discovered in the boundary between the Xingezhuang and Hongtuya formations (Wangshi Group) at Zangjiazhuang Village, Zhucheng City, Shandong Province, China, by workers from the Zhucheng Dinosaur Culture Research Center in 2008.
The holotype (ZJZ-57) is a nearly complete upper arm. Seven dinosaurs once carried the name of Zhucheng, but the first turned out to be synonymous with one that didn't:
Zhuchengosaurus maximus (Zhao et al., 2007)—synonymous with Shantungosaurus (Hu, 1973)
Zhuchengceratops inexpectus (Li et al.,2010)
Sinoceratops zhuchengensis (Xu et al., 2010)
Zhuchengtyrannus magnus (Hone et al., 2011)
Ischioceratops zhuchengensis (He et al., 2015)
Zhuchengtitan zangjiazhuangensis (Mo et al., 2017)
Sinankylosaurus zhuchengensis (Wang et al., 2020)
