Open Paleo

Jaklapallisaurus

Novas et al., 2010 yak-luh-pah-lee-sor-us

Named after Jaklapal village in Telangana, central India, near where the fossils were discovered, combined with Greek sauros (lizard); meaning 'Jaklapal lizard'

227.3–205.7 million years ago Norian, Late Triassic
Late Triassic stages

Jaklapallisaurus is a genus of unaysaurid sauropodomorph dinosaur. It lived during the Late Triassic period (early to middle Norian) in what is now Telangana, central India. The genus is monotypic, only including the species Jaklapallisaurus asymmetricus.

Under dispute

Jaklapallisaurus asymmetricus was one of the three founding members of Unaysauridae (Müller and colleagues, 2018), and the redescription of its holotype by Ezcurra and colleagues (2023) recovered it as a unaysaurid at the base of Plateosauria, in a clade sister to Plateosauridae. Support for that framework is weak even within the study that provides it: resampling frequencies for Unaysauridae and for the Unaysauridae plus Plateosauridae clade fall below 30%, and Jaklapallisaurus was flagged as one of the unstable terminals, although the Jaklapallisaurus plus Macrocollum pairing itself scored higher. Two later analyses do not recover the taxon as a unaysaurid at all, instead placing it among early-branching sauropodomorphs outside Plateosauria: Wang and colleagues (2025), and Barrett and colleagues (2026), who recover a monophyletic Unaysauridae that excludes it.

Diagnosis

  1. Femur with distal transverse width more than 1.5 times the anteroposterior depth across the medial condyle
  2. Medial distal condyle of the femur sub-triangular in distal view
  3. Distal end of the femur with a straight anterior margin
  4. Proximal end of the tibia with poorly asymmetric posterior condyles
  5. Distal end of the tibia with a concave posteromedial border
  6. Astragalus with the medial condyle strongly developed anteriorly (medial end 1.6 times deeper than the lateral) and a tuber on the lateral half of the ventral surface

Species

Jaklapallisaurus asymmetricus Novas et al., 2010

Type species

From Latin 'asymmetricus' meaning 'asymmetrical', referring to the highly asymmetrical astragalus of this species in distal view.

Holotype
ISIR 274 , Geology Museum, Indian Statistical Institute
Material
A probable anterior dorsal vertebra, an anterior caudal vertebra, the right distal femur, right tibia, right astragalus, right metatarsals I-IV, and right pedal phalanges I-1 and II-1.
Horizon
upper Maleri Formation, Norian, Late Triassic , 227.3–205.7 million years ago
Locality
3 km north of Jaklapalli village, Telangana, India

Synonyms

  • Jaklapallisaurus asymmetrica emended spelling

    The original spelling of Novas and colleagues (2010); changed to the masculine asymmetricus by Ezcurra and colleagues (2023) to agree with the genus.

References

  1. Novas, F. E.; Ezcurra, M. D.; Chatterjee, S.; Kutty, T. S. (2010). New dinosaur species from the Upper Triassic Upper Maleri and Lower Dharmaram formations of Central India. Earth and Environmental Science Transactions of the Royal Society of Edinburgh 101(3-4): 333-349. Cambridge University Press (CUP). doi:10.1017/S1755691011020093 novas2010a
  2. Müller, R. T.; Langer, M. C.; Dias-da-Silva, S. (2018). An exceptionally preserved association of complete dinosaur skeletons reveals the oldest long-necked sauropodomorphs. Biology Letters 14(11): 20180633. The Royal Society. doi:10.1098/rsbl.2018.0633

    Erected Unaysauridae with Jaklapallisaurus as the sister taxon of Macrocollum.

    müller2018a
  3. Ezcurra, M. D.; Müller, R. T.; Novas, F. E.; Chatterjee, S. (2023). Osteology of the sauropodomorph dinosaur Jaklapallisaurus asymmetricus from the Late Triassic of central India. The Anatomical Record. Wiley. doi:10.1002/ar.25359

    Comprehensive osteological redescription of the holotype with an emended diagnosis; recovers Jaklapallisaurus as a unaysaurid at the base of Plateosauria.

    ezcurra2023a
  4. Wang, Y. M.; Zhang, Q. N.; Wang, Y. C.; Xu, H.; Chen, J.; Feng, Z.; Xu, X.; Wang, T.; You, H. L. (2025). A new Early Jurassic dinosaur represents the earliest-diverging and oldest sauropodomorph of East Asia. Scientific Reports 15(1). Springer Science and Business Media LLC. doi:10.1038/s41598-025-12185-2

    Recovered Jaklapallisaurus among early-branching sauropodomorphs outside Plateosauria.

    wang2025a
  5. Barrett, P. M.; Botha, J.; Sciscio, L.; Stuart, B. P.; Lovegrove, J.; Munyikwa, D.; Zondo, M.; Broderick, T. J.; Edwards, S. F.; Mbambo, E.; Chapelle, K. E. J.; Dollman, K. N.; Tolan, S.; Choiniere, J. N. (2026). A new sauropodomorph dinosaur from the Pebbly Arkose Formation (Upper Triassic: Norian) of Kariba, Zimbabwe. Journal of Systematic Palaeontology 24(2): 2678610. Informa UK Limited. doi:10.1080/14772019.2026.2678610

    Recovered a monophyletic Unaysauridae that excludes Jaklapallisaurus.

    barrett2026a
  6. Jones, B. (2026). The Princeton Encyclopedia of Dinosaurs: Sauropods. Princeton University Press.

    Source of the body length, mass, and hip height estimates.

    jones2026b