Tomás Ezequiel Pedernera

La comunicación pública de la ciencia y la extensión universitaria tienen como objetivo en común acercar la ciencia a un público distinto fomentando la participación ciudadana y la construcción de una cultura científica. En este ensayo relato brevemente mi recorrido personal y profesional en paleontología y divulgación científica, y busco resaltar la importancia de comunicar la paleontología de manera accesible y contextualizada, poniendo el foco en la valoración del patrimonio paleontológico. En Argentina, estas actividades adoptan múltiples formatos, desde charlas abiertas hasta transmisiones digitales o streams. La curricularización de la extensión universitaria y la divulgación científica en las carreras de grado y posgrado busca dar lugar a profesionales que además de generar conocimiento tengan las habilidades para comunicarlo, no sólo a otros/as colegas sino también a un público ajeno a la disciplina.

The Triassic paleofloras of Argentina are mainly known for their vegetative elements. During the last decade, several contributions have focused on the study of Triassic reproductive structures. Here, we provide new information on reproductive structures recovered from two Triassic units from the central-west of Argentina: the Agua de la Zorra Formation (Cuyana Basin) and the Los Rastros Formation (Ischigualasto-Villa Unión Basin). These specimens had been described in previous contributions, however, the taxonomic assignment of the materials remained undetermined. In this work, a redescription of the materials is provided, allowing the taxonomic assignment of the specimens. The Agua de la Zorra Formation female reproductive structures were assigned to Matatiella sp. (Matatiellaceae) and to Rissikiostrobus reductus (Podocarpaceae). The female strobilus specimen registered in the Los Rastros Formation was assigned to the genus Umkomasia (Umkomasiaceae). This contribution represents a step forward to a better understanding of the reproductive structures for the Triassic of Gondwana. Keywords: Matatiella, Rissikiostrobus, Umkomasia, Gondwana, Argentina.

The impact of volcanic activity and trophic state on the preservation of plant remains from two Triassic palaeolake deposits in western Gondwana is investigated. Six taphonomic modes are identified for the Potrerillos–Cacheuta sequence and the Los Rastros Formation, along with proposed taphonomic pathways for each mode. The taphonomic pathways were compared with those proposed for the Agua de la Zorra Formation, a coeval lacustrine‐deltaic succession. In all three cases, plant preservation in off‐shore lacustrine facies was enhanced by anoxic bottom conditions. In the more proximal near‐shore facies, a high sedimentation rate would have been factor that enhanced the preservation. Variation in relative abundance and taxonomic diversity between the three successions are attributed to ecological differences rather than taphonomic differences among the lake systems. No evidence was recorded that the preserved plant material was produced by volcanic trauma. The preservation of the cuticle recorded in the Cacheuta Formation was likely enhanced by the apparently low thermal maturation of the rock and the presence of tuffaceous horizons. In the three successions, the abundance and distribution of remains throughout the sections suggest that the trophic state of the lake did not influence the preservation of the plant.

Volcanic eruptions have an impact on the paleoecology of plant communities and their preservation in the fossil record. The aim of this contribution is to evaluate the influence of volcanism on plant preservation in lacustrine settings via systematic sampling and chemical analyses of fossil plants in the Upper Triassic Agua de la Zorra Formation, of the Argentinian Cuyana Basin. Plant remains are not uniformly preserved throughout the Agua de la Zorra Formation and their stratigraphic distribution reflects the original spatial pattern of the plant communities. SEM-EDX analyses was used to demonstrate how volcanism affected diagenesis of the plant remains. Eight taphonomic modes were determined from biostratinomic analysis, and three preservational modes from the chemical features observed in the SEM-EDX spectra. The three preservation modes recognized by SEM-EDX analysis are more likely linked to diagenesis and are not equivalent to the taphonomic modes described based on the biostratinomic features. The Agua de la Zorra paleolake preferentially preserved plant material because of anoxic conditions in deeper parts of the lake, and a high sedimentation rate in proximal near-shore facies. The plant remains are most abundant in sandy facies deposited by high-energy flows but there is no evidence that these flows were pyroclastic nor that the plant remains were generated by volcanic trauma.

In the North of Mendoza Province, at Paramillos de Uspallata locality, Triassic sedimentary rocks outcrop. These Triassic beds are grouped in four formations: Paramillos, Agua de la Zorra, Portezuelo Bayo and Los Colorados. The Agua de la Zorra Formation is characterized by deposition in a deltaic and lacustrine system. The aims of this contribution are: (1) to realize a systematic study of new plant remains found in the Agua de la Zorra Formation and (2) to analize the influence of the potential of preservation and the volcanism in the Agua de la Zorra taphoflora in contrast with other Triassic units. Plant remains were systematically collected and compared with taphofloras from other Triassic formations of the Cuyana Basin. The systematic study from the Agua de la Zorra Formation allowed the determination of 21 taxa, nine of which have been cited in a previous contribution and 12 were described for the first time for the Agua de la Zorra Formation. There are differences in the taxonomic diversity between the taphofloras recovered from Potrerillos and Paramillos formations and these differences are linking with differences in biostratinomic process in each fluvial system and linked with the evidence of volcanic processes in these areas. The differences in diversity in the taphofloras of the Cacheuta and Agua de la Zorra formations can be more associated to ecological differences than variations in the taphonomic processes in each of the lake systems.