Open Paleo

Haestasaurus

Upchurch et al., 2015 HAY-stuh-SOR-us

Named after Haesta, a Saxon chieftain associated with the Hastings area of England near where the fossil was found, combined with Greek 'sauros' meaning 'lizard'; means 'Haesta's lizard'.

137.1–132.6 million years ago Valanginian, Early Cretaceous
Early Cretaceous stages

Haestasaurus is a genus of herbivorous sauropod dinosaur, belonging to the Macronaria, that during the Early Cretaceous lived in the area of present-day England. The only species is Haestasaurus becklesii.

Under dispute

Haestasaurus has been recovered in markedly different positions. Upchurch and colleagues (2015) obtained analyses ranging from the base of Macronaria to within Titanosauria but concluded it is most plausibly a non-titanosauriform macronarian; Mannion and colleagues (2019) instead recovered it outside Neosauropoda, as sister to Janenschia. Jones (2026) is explicitly non-committal.

Diagnosis

  1. Anteromedial corner of distal humerus projects to form anterior entepicondylar process
  2. Two small vertical ridges between lateral and medial anterodistal processes of humerus
  3. Proximal articular surface of radius widest anteroposteriorly along lateral margin, nearly straight rather than strongly convex
  4. Anterior surface of radius shallowly concave at distal end shaft between anterolateral and anteromedial ridges
  5. Combination of robust ulna and slender radius

Species

Haestasaurus becklesii Upchurch et al., 2015

Type species

Named for Samuel Husband Beckles, the collector who obtained the holotype block from the coast of East Sussex in 1852.

Holotype
NHMUK PV R 1868, NHMUK PV R 1870 , Natural History Museum
Material
Associated left humerus, ulna, radius, and skin impression from near elbow region
Horizon
Wealden Group, Valanginian, Early Cretaceous , 137.1–132.6 million years ago
Locality
the coast near Hastings, East Sussex, United Kingdom Upchurch and colleagues (2015) give the unit as the Hastings Beds Group, a name the British Geological Survey no longer recognizes, and record the exact locality as unknown.

References

  1. Upchurch, P.; Mannion, P. D.; Taylor, M. P. (2015). The Anatomy and Phylogenetic Relationships of "Pelorosaurus" becklesii (Neosauropoda, Macronaria) from the Early Cretaceous of England. PLOS ONE 10(6): e0125819. Public Library of Science (PLoS). doi:10.1371/journal.pone.0125819

    Original description; concluded Haestasaurus is most plausibly a non-titanosauriform macronarian, though its analyses ranged from basal Macronaria to within Titanosauria.

    upchurch2015a
  2. Jones, B. (2026). The Princeton Encyclopedia of Dinosaurs: Sauropods. Princeton University Press.

    Source of the body length estimate.

    jones2026b
  3. Mannion, P. D.; Upchurch, P.; Schwarz, D.; Wings, O. (2019). Taxonomic affinities of the putative titanosaurs from the Late Jurassic Tendaguru Formation of Tanzania: phylogenetic and biogeographic implications for eusauropod dinosaur evolution. Zoological Journal of the Linnean Society 185(3): 784-909. Oxford University Press (OUP). doi:10.1093/zoolinnean/zly068

    Recovered Haestasaurus outside Neosauropoda, as sister to Janenschia.

    mannion2019a