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The Pliocene lacustrine infill of Camp dels Ninots maar (Girona, Spain) hosts an exceptional record of complete articulated skeletons. Here we present the taphonomical description of 22 fossil water frogs recovered from the Pit 7/8 of Can Argilera Sector. Description of their skeletal taphonomy is done on the basis of their distribution, completeness, articulation and limb position, and by establishing comparisons with the late Miocene site of Libros (Spain). Microscopic examination shows no evidence of digestion and absence of weathering. Mass mortality or any environmental stress-induced factors cannot be ruled out, but natural death seems to be the most probable. Limited time of decay prior burial seems to be the main pattern explaining the relatively high degree of articulation and completeness. Floatation is not to be disregard for some more (proximally) disarticulated specimens. Taphonomical patterns document two types of sub-environments inside a cool and deep lake, suggesting a more complex depositional scenario for Camp dels Ninots than the ones described in others similar Konservat-Lagerstätten. [ABSTRACT FROM AUTHOR]

Climate conditions during the Pliocene Climate Optimum (3.2 - 2.5 Ma) are significant due to their proposed correspondence with future climate. There are various difficulties involved in obtaining terrestrial temperatures for this period, so new sources of information are therefore important. This work proposes a new approach based on frog body size, facilitating a palaeoclimate reconstruction of the palaeontological site of Camp dels Ninots (Caldes de Malavella, NE Spain), a Pliocene Konservat-Lagerstatte, dated at around 3.2 Ma. For this purpose, an extensive database of current populations of the genus Pelophylax from across Eurasia has been generated making it possible to establish a correlation between frog body size and eco-climate parameters such as temperature, precipitation rates and real evapotranspiration. Eco-climate values were obtained using OLS regression models and compared with previous palaeoclimate reconstructions from other archaeo-palaeontological sites of interest (Barranco Leon and Fuente Nueva 3, SE Spain). Our new proxy results in a palaeotemperature of 14.3 ± 2.6°C and a palaeoprecipitation rate of 846.8 ± 165.4 mm; according to primary productivity values, a 'Summer-green broad-leaved forest'-like biome is proposed for Camp dels Ninots, in line with previous palaeobotanical studies. The new values generated for the other sites follow the same trends as previous reconstructions, although with lower values in most cases, especially in terms of temperature. This method is a promising new approach to complement previous palaeoclimate reconstructions and could also generate new data. [ABSTRACT FROM AUTHOR]