Open Paleo

Mamenchisauridae

Young & Zhao, 1972 Type genus Mamenchisaurus

Its genera lived 174.7–137.1 million years ago Middle Jurassic–Early Cretaceous

Mamenchisauridae is a family of eusauropod dinosaurs known from the Jurassic and Early Cretaceous of Asia and Africa, best known for their proportionately extremely long necks. The group was predominantly a Chinese radiation, including such genera as Mamenchisaurus, Omeisaurus, Chuanjiesaurus, Eomamenchisaurus, and Tonganosaurus, but its range extended to the Tanzanian outlier Wamweracaudia and, based on fragmentary remains, into Siberia. Some members reached gigantic sizes, ranking among the largest of all sauropods. The family has historically been confused with the somphospondylan Euhelopus and its relatives, and some phylogenetic analyses have again recovered Euhelopus within the mamenchisaurid lineage, which then takes the name Euhelopodidae (Moore and colleagues, 2020).

Diagnosis

  1. Exceptionally elongate cervical vertebrae yielding necks approaching half the total body length
  2. High cervical count, commonly 17 to 19 cervical vertebrae
  3. Vertically oriented, often unbifurcated cervical neural spines
  4. Forked anterior chevrons and, in derived forms, accessory processes on the humerus
  5. Procoelous anterior caudal centra in derived members

Genera placed directly in Mamenchisauridae

  • Analong Ren et al., 2020 Bajocian (170.9–168.2 Ma)China
  • Anhuilong Ren et al., 2020 Middle JurassicChina
  • Chuanjiesaurus Fang et al., 2000 Bajocian (170.9–168.2 Ma)China
  • Eomamenchisaurus Lü et al., 2008 Aalenian–Bathonian (174.7–165.3 Ma)China
  • Huangshanlong Huang et al., 2014 Middle JurassicChina
  • Hudiesaurus Dong, 1997 Kimmeridgian–Tithonian (154.8–143.1 Ma)China
  • Jingiella Ren et al., 2025 Kimmeridgian (154.8–149.2 Ma)China
  • Klamelisaurus Zhao, 1993 Callovian (165.3–161.5 Ma)China
  • Mamenchisaurus Young, 1954 Oxfordian–Tithonian (161.5–143.1 Ma)Chinaunder dispute
  • Omeisaurus Young, 1939 Bajocian–Oxfordian (170.9–154.8 Ma)China
  • Qijianglong Xing et al., 2015 Late JurassicChina
  • Rhomaleopakhus Upchurch et al., 2021 Kimmeridgian–Tithonian (154.8–143.1 Ma)China
  • Tienshanosaurus Disputed Young, 1937 Bathonian–Oxfordian (168.2–154.8 Ma)China
  • Tonganosaurus Li et al., 2010 Early JurassicChina
  • Tongnanlong Wei et al., 2025 Late JurassicChina
  • Uragasaurus Nilpanapan et al., 2026 Tithonian–Berriasian (149.2–137.1 Ma)Thailand
  • Wamweracaudia Mannion et al., 2019 Tithonian (149.2–143.1 Ma)Tanzania
  • Xinjiangtitan Wu et al., 2013 Callovian–Oxfordian (165.3–154.8 Ma)China
  • Yuanmousaurus Lü et al., 2006 Aalenian–Bathonian (174.7–165.3 Ma)China
  • Zigongosaurus Disputed Hou et al., 1976 Bajocian–Oxfordian (170.9–154.8 Ma)China

References

  1. Young, C. C.; Zhao, X. (1972). Mamenchisaurus hochuanensis sp. nov. Institute of Vertebrate Palaeontology and Palaeoanthropology Monographs, Series A 8: 1-30.

    Erected Mamenchisauridae for Mamenchisaurus hochuanensis.

    young1972a
  2. Naish, D.; Martill, D. M. (2007). Dinosaurs of Great Britain and the role of the Geological Society of London in their discovery: basal Dinosauria and Saurischia. Journal of the Geological Society 164(3): 493-510. doi:10.1144/0016-76492006-032

    Defined Mamenchisauridae as all sauropods closer to Mamenchisaurus constructus than to Saltasaurus loricatus.

    naish2007a
  3. Moore, A. J.; Upchurch, P.; Barrett, P. M.; Clark, J. M.; Xu, X. (2020). Osteology of Klamelisaurus gobiensis (Dinosauria, Eusauropoda) and the evolutionary history of Middle-Late Jurassic Chinese sauropods. Journal of Systematic Palaeontology 18(16): 1299-1393. doi:10.1080/14772019.2020.1759706

    Phylogeny of Chinese eusauropods in an osteology of Klamelisaurus; their clade is Mamenchisauridae in one analysis and, with Euhelopus inside it, Euhelopodidae in the others.

    moore2020a
  4. Moore, A. J.; Barrett, P. M.; Upchurch, P.; Liao, C. C.; Ye, Y.; Hao, B.; Xu, X. (2023). Re-assessment of the Late Jurassic eusauropod Mamenchisaurus sinocanadorum Russell and Zheng, 1993, and the evolution of exceptionally long necks in mamenchisaurids. Journal of Systematic Palaeontology 21(1). doi:10.1080/14772019.2023.2171818

    Reviewed the published definitions of Mamenchisauridae and adopted that of Naish and Martill (2007).

    moore2023a