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Scientific practices stemming from colonialism, whereby middle- and low-income countries supply data for high-income countries and the contributions of local expertise are devalued, are still prevalent today in the field of palaeontology. In response to these unjust practices, countries such as Mexico and Brazil adopted protective laws and regulations during the twentieth century to preserve their palaeontological heritage. However, scientific colonialism is still reflected in many publications describing fossil specimens recovered from these countries. Here, we present examples of ‘palaeontological colonialism’ from publications on Jurassic–Cretaceous fossils from NE Mexico and NE Brazil spanning the last three decades. Common issues that we identified in these publications are the absence of both fieldwork and export permit declarations and the lack of local experts among authorships. In Mexico, access to many fossil specimens is restricted on account of these specimens being housed in private collections, whereas a high number of studies on Brazilian fossils are based on specimens illegally reposited in foreign collections, particularly in Germany and Japan. Finally, we outline and discuss the wider academic and social impacts of these research practices, and propose exhaustive recommendations to scientists, journals, museums, research institutions and government and funding agencies in order to overcome these practices.

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A new vertebrate tracksite in southeastern Coahuila, northern México, known as the El Pelillal tracksite (Latest Campanian, Cerro del Pueblo Formation) has yielded an important ichnofauna that includes the tracks of turtles, crocodilians, a small theropod dinosaur, a mammal-like organism and the tracks of pterosaurs. The pterosaurian manus impressions share an extraordinary similarity, in size and morphology, with the Jurassic ichnogenus Pteraichnus Stokes 1957 and are referred to Pteraichnus sp.; however, the pes impressions differ in that they are rather very elongated. According to the geological features and ichnofauna the El Pelillal tracksite represents a shallow, freshwater or lacustrine deposit, which agrees with our knowledge about the habitat preference of Cretaceous pterosaurs. This newly discovered tracksite in southeastern Coahuila, Mexico, offers great potential for palaeoichnological research and is thus becoming important in the understanding of the palaeoecosystems during the Late Cretaceous in southern North America.

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A track-bearing locality in one of the shores of the Ñumí River, near the City of Tlaxiaco, northwestern Oaxaca, southern Mexico, preserves the footprints of sauropod and theropod dinosaurs; it is located within the stratigraphic sequence of the Zorrillo-Taberna Indiferenciadas Formation, of Middle Jurassic (Bajocian) age. A well-preserved manus-pes set of ankylosaurian affinity (Tetrapodosaurus) is preserved on a rock block from this formation. These tracks are preserved as convex hyporeliefs. The pes impression is tetradactyl, with ventrally curved toe tips, suggesting that these were deeply impressed in the sediment. Manus impression is pentadactyl, with short and blunt digits. A curved structure preserved together with these footprints is herein interpreted to be a tail drag. The stratigraphic unit from whence this block came was identified and two additional ankylosaurian tracks, were found preserved in situ as natural sandstone casts. An isolated handprint, has the same features that fit the ankylosaurian hand morphology; however, some features such as a medio-lateral concavity are indicative of the presence of a well-developed palmar pad, and could suggest the functional mechanics of the ankylosaurian manus. The Zorrillo-Taberna Indiferenciadas Formation is a coal-bearing formation; after the global record, ankylosaur footprints are concentrated in coal-bearing and floodplain facies, thus suggesting, that at least the North American Ankylosauria were adapted to similar paleoecological conditions from Middle Jurassic to Early Cretaceous times. It represents the second report of ankylosaurian tracks from Mexico and the southernmost record of the ichnogenus Tetrapodosaurus in North America. In this way, it suggests a geographic continuum in the record of the Ankylosauria to southern North America during Middle Jurassic times. With their Middle Jurassic age, these footprints represent the oldest ankylosaurian ichnofossils known to date.

Dinosaur tracks have been identified near San Martín Atexcal, southern Puebla, Mexico, within the sedimentary sequence of the San Juan Raya Formation of Lower Cretaceous (Albian) age. The tracksite, located in the bed of the Magdalena River, reveals six different ichnofossiliferous levels identified within a 9 m thick sedimentary sequence. The inferred environment is that of a tidal (marginal marine) mudflat (Level I). Level I preserves three theropods trackways (?Allosauroidea), additionally, isolated tracks belonging to iguanodontids (Ornithopoda). Level II preserves faint iguanodontid tracks. Levels III to V preserve sauropod tracks. Younger level VI preserves, although morphologically different, a track belonging to Ornithopoda. The dinosaur tracks from San Martín Atexcal support the existence of continental facies within the San Juan Raya Formation; they represent the second record of dinosaur tracks from the Lower Cretaceous of Mexico and are part of an important but little documented record of Lower Cretaceous dinosaurs in Mexico.