Nagatitan
From Nāga, the mythological serpent-like creature of various Asian cultures (especially northeastern Thailand), and Greek 'titan' meaning 'giant'.
Early Cretaceous stages
Nagatitan is an extinct genus of euhelopodid sauropod dinosaur known from the Early Cretaceous (Aptian–Albian) Khok Kruat Formation of Thailand. The genus contains a single species, Nagatitan chaiyaphumensis, known from a partial postcranial skeleton. With an estimated body length of about 27 meters and a mass of 25–28 tonnes, it is the largest dinosaur currently known from Southeast Asia.
Diagnosis
- Hyposphene of middle dorsal vertebrae triangular, becoming a vertical ridge in posterior dorsal vertebrae (two distinct hyposphene morphologies within the dorsal series).
- Triangular anterior aliform processes on posterior dorsal neural spines, formed by the convergence of the SPRL and aSPDL at the ventral margin of the process.
- Spinopostzygapophyseal laminae of middle and posterior dorsal neural spines divided into lateral and medial branches throughout their entire length.
- Prominent bulge on the posterolateral margin of the humerus, approximately level with the deltopectoral crest, interrupting the lateral humeral margin in anterior view.
- Distal end of pubis transversely expanded along the lateral surface relative to the shaft.
- Proximal third of femur with anteroposteriorly narrowed lateral margin forming a flange-like trochanteric shelf bounded medially by a vertical ridge.
Species
Nagatitan chaiyaphumensis Sethapanichsakul et al., 2026
Type species
From Chaiyaphum, the province of northeastern Thailand where the holotype was discovered.
- Holotype
- SM2025-1-546, SM2025-1-547, SM2025-1-548, SM2025-1-549, SM2025-1-550, SM2025-1-551, SM2025-1-552, SM2025-1-553, SM2025-1-554, SM2025-1-555, SM2025-1-556 , Sirindhorn Museum
- Material
- Four dorsal vertebrae, five dorsal ribs, four sacral vertebrae, five sacral ribs, the right humerus, the right ilium, the left and right pubes, and a mostly complete right femur.
- Horizon
- Khok Kruat Formation, Aptian–Albian, Early Cretaceous , 121.4–100.5 million years ago
- Locality
- Ban Pha Nang Sua, Chaiyaphum, Thailand
References
- Sethapanichsakul, T.; Khansubha, S. O.; Manitkoon, S.; Hanta, R.; Mannion, P. D.; Upchurch, P. (2026). The first sauropod dinosaur from the Lower Cretaceous Khok Kruat Formation of Thailand enriches the diversity of somphospondylan titanosauriforms in southeast Asia. Scientific Reports 16(1): 12467. doi:10.1038/s41598-026-47482-x sethapanichsakul2026a