The newly-discovered theropod and sauropod footprints are part of the Late Jurassic Majala Formation, and represent the oldest dinosaur footprints reported for Chile and the western margin of the ancient supercontinent Gondwana.
Paleoartistic reconstruction of Quebrada Huatacondo during the Late Jurassic epoch. Image credit: Nahuel Vásquez.
“The Late Jurassic fossil record exhibits notable disparities in the abundance and distribution of dinosaur tracksites between Laurasia and Gondwana,” said Dr. Marko Yurac from the Unidad de Patrimonio Paleontológico and his colleagues.
“In Europe alone, several sites have been documented, including those in Italy, Croatia, Poland, Spain, Switzerland, France, Germany, and Portugal.”
“Additionally, North America hosts extensive tracksites with abundant ichnological evidence.”
“In contrast, the dinosaur track record in Gondwana is markedly more limited and fragmented. Notable exceptions include track-bearing outcrops in the High Atlas Mountains of Morocco.”
“Beyond these, ichnological evidence is relatively scarce, with only a few records from Australia.
“In South America, most dinosaur tracksites are concentrated along the eastern margin of the continent, particularly in Brazil, Guyana, and Uruguay, with additional reports from northern regions such as Colombia.”
“In contrast, the western margin of South America — corresponding to the western boundary of Gondwana — has yielded Late Jurassic dinosaur tracksites exclusively from Chile.”
Trackway with four consecutive tracks of a large tridactyl trackmaker in the Majala Formation in Chile. Image credit: Yurac et al., doi: 10.1186/s13358-025-00419-9.
The paleontologists identified a total of five track-bearing levels within the Majala Formation in the Quebrada Huatacondo area of Chile.
The footprints were produced by theropod and sauropod dinosaurs approximately 160 million years ago, during the Late Jurassic epoch.
“Around 160 million years ago, northern Chile experienced cycles of flooding and drought,” the researchers explained.
“While the climate was largely dry, seasonal water accumulation created ephemeral wetlands that attracted animals of all sizes — from small theropods to massive carnivorous dinosaurs.”
“As dinosaurs walked across damp mud near these water sources, their footprints were imprinted in the soft sediment.”
“Subsequent flooding gently covered the tracks, preserving them for millions of years.”
The Majala footprints reveal the presence of giant (lengths between 51 and 52.8 cm), large (lengths between 43.5 and 46.5 cm) and medium (lengths between 25 and 27 cm) theropod dinosaurs.
One surface has more than 25 footprints of minute to small theropods (footprints lengths ranging from 8 to 13 cm).
“These footprints constitute the smallest theropod tracks recorded so far in Chile, and possibly across the entire western margin of Gondwana,” the scientists said.
Another surface represents the sole stratigraphic level exhibiting exclusively sauropod tracks (potentially undertracks).
“Due to their poor preservation state, quantitative measurements could not be obtained,” the authors said.
“Nevertheless, analysis of the digital model enables the inference of the presence of at least 9 footprints that show an alignment which could correspond to a possible trackway.”
According to the paleontologists, their finds represent the oldest dinosaur tracks known from Chile and the western margin of Gondwana.
“These footprints serve as the primary evidence for reconstructing the paleoenvironmental and behavioral dynamics of dinosaurs in northern Chile during the Late Jurassic, reflecting episodic occupation of semi-arid floodplain and ephemeral wetland habitats,” they concluded.
The discovery is reported in a paper in the Swiss Journal of Palaeontology.
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M. Yurac et al. 2025. Upper Jurassic dinosaur tracks from the Majala Formation in the Huatacondo area (Tarapacá Basin, Chile): reappraisal of known localities and new tracksite discoveries. Swiss J Palaeontol 144, 72; doi: 10.1186/s13358-025-00419-9
