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Well-preserved tracks of the wild boar Sus scrofa are described from the Matalascañas Trampled Surface (MTS) in the upper Pleistocene aeolian basal unit of the El Asperillo Cliff, Huelva (southwestern Spain). These are the first published tracks of suid pigs in the fossil record, here formally described as Suidichnus galani igen. and isp. nov. A revision of valid artiodactyl ichnogenera is provided for comparison. The large size of wild boar found in the Late Pleistocene of Spain contradicts the general trend towards smaller size known for the evolution of the species and the Bergmann's ecogeographical rule for the extant subspecies. In the present case, the remarkable large size that can be reached by these tracks is discussed as an ecomorphological adaptation of wild boars to either resource bonanza, and/or predation pressure during the Last Interglacial. The large S. scrofa scrofa identified in MTS corresponds to some of the earliest evidences known to this subspecies in Iberia.

Trace fossils are important evidence of benthic activity, but they have received less study than body fossils for investigating the aftermath of the end-Permian extinction. There is therefore a need to document Lower Triassic ichnofaunas to understand their significance with respect to the end-Permian crisis. In light of this need, this paper describes a novel Lower Triassic ichnosite at Mount Pallone (Carnic Alps, Italy), where the Campil Member (Smithian) of the Werfen Formation (Griesbachian–Spathian) presents an abundant ichnofauna characterized by excellent preservation and low diversity. Documented ichnogenera include Asteriacites lumbricalis, Gyrochorte comosa, Diplocraterion habichi and Planolites beverleyensis. The ichnofaunal composition and the bioturbation style suggest a marginal marine paleoenvironment ranging from intertidal to shallow subtidal settings. Storm influence, hydrodynamic energy, sedimentation rate, freshwater input and/or water temperature played an important role in structuring the benthic ecosystem. Dense (300 specimens/m2) aggregations of the trace fossil Asteriacites lumbricalis reveals social behavior of their inferred brittlestar producers (Echinodermata, Ophiuroidea). In line with modern brittlestar beds, social behavior provided significant advantage because raised arms of brittlestars dampened hydrodynamic energy. This study suggests that Asteriacites beds may be considered ichnological proxies for marine settings, low bioturbation intensity, shallow tiering, high sedimentation rate and/or event-bed deposition, significant levels of hydrodynamic energy, and low predation pressure. The studied ichnofauna reflects stressed environmental conditions, but it is unclear whether this reflects local brackish conditions (‘Gazpacho model’) or global hot temperatures (‘Hot Soup model’).

This work describes the occurrence of numerous, nearly intact Mecochirus rapax populations within Thalassinoides suevicus burrows in the Lower Cretaceous Boca do Chapim Formation. This exceptional preservation allows for unquestionable attribution of a specific producer to a biogenic structure. Analysis of sedimentological features combined with functional morphology and ichnological inferences suggests that the unique preservation of the fauna resulted from river flood depositional events that buried successive Mecochirus populations in a shallow marine setting.