Euhelopus
From Greek 'helos' meaning 'swamp' and Greek 'pous' meaning 'foot', giving 'true marsh-foot' (prefix 'eu-' meaning 'true' was added by Romer in 1956 when renaming from Helopus); the name refers to the marshy area of the finds and to Swedish swamp shoes (truga) which Wiman said resembled the animal's wide feet.
Euhelopus is a genus of sauropod dinosaur that lived between 143 and 133 million years ago during the Berriasian and Valanginian ages of the Early Cretaceous in what is now Shandong Province in China. It was a large quadrupedal herbivore. Like sauropods such as brachiosaurids and titanosaurs, Euhelopus had longer forelimbs than hindlimbs. This discovery was paleontologically significant because it represented the first dinosaur scientifically investigated from China — seen in 1913, rediscovered in 1922, excavated in 1923, and studied by T'an during the same year.
Diagnosis
- Teeth procumbent, with an asymmetrical crown-to-root margin (mesial margin nearer the crown apex) and well-developed crown buttresses on the mesiolingual surface
- Cervical neural arches with an epipophyseal-prezygapophyseal lamina dividing two pneumatocoels throughout the cervical series
- Anterior cervical ribs with three costal spurs on the tuberculum and capitulum; middle cervical ribs hanging well below the centrum on elongate parapophyses and capitula
- Presacral neural spines 16 to 21 trifid, with a median tubercle as large as or larger than the metapophyses
- Middle and posterior dorsal parapophyseal and diapophyseal laminae crossing to form a K-shaped configuration on the lateral face of the neural arch
- Presacral pneumaticity extending into the ilium
Species
Euhelopus zdanskyi (Wiman, 1929)
Type species
First named as Helopus zdanskyi
Named for Otto Zdansky, the Austrian student who excavated the holotype and a second skeleton from Shandong Province, China, in 1923.
- Holotype
- PMU 24705 , Paleontological Museum
- Formerly
- PMU R 233 (renumbered)
- Material
- A partial skull with lower jaws, an articulated presacral column (axis through the 25th presacral) with cervical ribs, a dorsal rib, and the left femur.
- Notes
- The holotype as originally constituted also included exemplar c, whose accession number and whereabouts are unknown, so it cannot be listed.
- Horizon
- Mengyin Formation, Berriasian–Valanginian, Early Cretaceous , 143.1–132.6 million years ago
- Locality
- Ningchiakou, Shandong, China
Synonyms of the genus
| Name | Type | Reason |
|---|---|---|
| Helopus | preoccupied | Name preoccupied by Helopus (Aves). |
Notable specimens
-
Exemplar b
PMU 24706 Paleontological Museum Found 1923 by Otto Zdansky complementary
Referred second skeleton, of an individual about as large as the holotype, preserving anatomy absent in the type: nine articulated dorsal vertebrae and sacrum, two dorsal ribs, a nearly complete pelvis, and a right hindlimb.
References
-
Wiman, C. (1929). Die Kreide-Dinosaurier aus Shantung [The Cretaceous dinosaurs from Shantung]. Palaeontologia Sinica, Series C 6(1): 1-67.
In German. Original description as Helopus zdanskyi; Helopus was preoccupied (Helopus caspius Wagler, 1832, a tern) and the genus was renamed Euhelopus by Romer (1956).
wiman1929a -
Romer, A. S. (1956). Osteology of the Reptiles. 772 pp. University of Chicago Press, Chicago.
Renamed Helopus zdanskyi Wiman, 1929 to Euhelopus zdanskyi because Helopus was preoccupied.
romer1956a -
Wilson, J. A.; Upchurch, P. (2009). Redescription and reassessment of the phylogenetic affinities of Euhelopus zdanskyi (Dinosauria: Sauropoda) from the Early Cretaceous of China. Journal of Systematic Palaeontology 7(2): 199-239. doi:10.1017/S1477201908002691
Modern redescription and phylogenetic reassessment of Euhelopus zdanskyi.
wilson2009a -
Jones, B. (2026). The Princeton Encyclopedia of Dinosaurs: Sauropods. Princeton University Press.
Source of the hip height estimate, and the appearance features.
jones2026b