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Non-marine bivalves are key fossils in Permian continental stratigraphy and palaeogeography. Although known since the end of 19th century, the occurrences from the continental basins of the Southern Alps have never been extensively studied. The non-marine bivalves from the Lower Permian Collio Formation (Brescian pre-Alps) are herein revised, and those from the Guncina Formation (Athesian District) are described for the first time. These two units yielded non-marine bivalves belonging to the genus Palaeomutela sensu lato, which is widespread in the Permian continental successions of eastern Euramerica. Three Palaeomutela morphotypes have been herein described: oval-subtriangular, subtrapezoidal and elongated. The latter includes several specimens herein assigned to Palaeomutela (Palaeanodonta) berrutii sp. nov. and dominates the Collio Formation association. The Guncina Formation yielded also the genus Redikorella, for the first time co-occurring on the same stratigraphic horizon of Palaeomutela, herein assigned to Palaeomutela (Palaeanodonta) guncinaensis sp. nov. To-date, it was generally accepted that the first members of the genera Palaeomutela and Redikorella occurred during the Ufimian (late Kungurian of the global scale) in the non-marine basins of the Cis-Ural Foredeep and of Angara, respectively. Such new finds in the early-middle Kungurian of southwestern Europe, well constrained by radioisotopic dating, suggest new global first appearance (First Appearance Datum) and a possible new center of origin of these genera. This fact raises new questions on biostratigraphy, palaeobiogeography and palaeoecology, which will require further research. If we assume that the genera Palaeomutela and Redikorella had only one center of origin, we need to hypothesise possible migration routes from SW Europe to the continental basins of Eastern Europe and Angara. Apparently, such migration could be better supported by a Pangaea B palaeogeographic configuration.

This work provides a more precise up-to-date biostratigraphical framework of the Early Jurassic ammonite succession of the Brescian Prealps with more than seventy taxa for the Sinemurian, Pliensbachian and basal Toarcian corresponding to a about 30 horizons or faunal assemblages rather well correlable with the NW European standard zonation. These results are supported with already published data, new data from recent field investigations, revised contributions of different authors and with the study of the historical collection of the Museum of Natural Sciences of Brescia (Northern Italy). The biohorizons are referred to the Lower Jurassic carbonate series of the Brescian Prealps, cropping out between the eastern surroundings of Brescia (Botticino-Serle), to the East, and the Lake Iseo, to the West. This area was located in the eastern border of the wide Lombardian Basin, a part of the southern continental passive margin subjected to the Jurassic rifting, preceding the Neo-Tethys opening.

A new Late Triassic tetrapod tracksite was discovered north of the Zone village, on the north-eastern side of the Iseo Lake (Southern Alps, Brescia, Lombardy). The tracks are preserved on two distinct bedding planes, belonging to the lower/middle Carnian Val Sabbia Sandstone. The ichnoassemblage is composed of about seventy footprints, organized in six quadrupedal trackways exhibiting both wide and narrow gauge. All the trackways can be attributed to a crurotarsan archosaur trackmaker and at least three of them could be assigned with confidence to the ichnogenus Brachychirotherium Beurlen 1950. If we exclude a dubious Brachychirotherium specimen track from Mt. Pelmetto (Dolomites), the Zone material represents the first well documented report of this ichnogenus from the Upper Triassic of Northern Italy. The footprints have been analyzed both with traditional methods, and with 3D technologies, such as the terrestrial laser scanner. The ichnoassemblage, although not exceptionally preserved, adds new important data for the stratigraphic distribution of crurotarsan tracks in the Triassic of Southern Alps.