These large gastropods were ornamented with spines or tubercles, partly to reinforce their shells and partly to be able to hide in amongst the gravel right at the contact with the rough waters, where this association used to live. The organisms were then transported into deeper waters forming the deposits we now call 'Pachycardia Tuff'. 

These spherical snails could grow to a considerable size and were able to remain stable on powerful waves thanks to their smooth surface. We can imagine these molluscs were brightly coloured, as a few specimens reveal traces of colour, even if we do not know yet which colour they were. 

This bivalve mollusc makes up 90 percent of the fossils in the Pachycardia Tuff layers, which explains where they got their name from! These layers of coarse sediments (sandstone and conglomerates with rounded gravel of volcanic origin) are only found on Alpe di Siusi and represent deposits containing organisms that lived on the beaches of the volcanic islands, where the waves were very strong. Pachycardia has a very thick shell that made it resistant to the force of water.

Palm trees were missing on the volcanic islands of the Triassic atolls, as they were not to turn up until over 100 million years later! Yet there were palmlike trees that were related to primitive plants today represented by the ginkgo or sago cycad. Pterophyllum belongs to the now-extinct Benettitales, which populated the coasts in the Triassic period along with primitive conifers and ferns. Palm trees would not have been a feature of these beaches! 

Nowadays, coral reefs are one of the most spectacular environments thanks to the beauty, shape and colour of its organisms. This ecosystem finally managed to recover during the Late Ladinian period, after a big crisis following the mass extinction. The large coral colonies found in abundance on the Alpe di Siusi plateau bear witness to this significant biological event. 

Daonella are typical bivalve molluscs from the Middle Triassic period (247-237 million years). Their thin, flat shells were reinforced with radiating ribs that, beside their circular to sub-triangular shell outline, characterize the species. Daonella lommeli is one of the largest and most widespread species. As it is often found in rocks deposited in the open sea, it is presumed that it lived afloat the water thanks to its thin, wide shell.

The most famous fossil in Val Gardena is definitely the ichthyosaur found on the Secëda mountain. This large marine reptile, around 5 meters long, was the largest predator of its time (241-240 million years ago). As much of its skeleton is missing, it cannot definitely be allocated to a specific genus. Yet it remains a very significant discovery, as it is practically unique in the Early Ladinian period, a time of crisis for these marine reptiles.  

Ammonites were cephalopods, relatives of today's nautilus, octopus and squid. They are extinct now, but used to be among the most common organisms living in the Triassic seas. There are many examples of their fossilised remains, ranging from perfectly 3-dimensional to completely flattened. The rapid morphological changes in many groups make them an important tool in rock dating. Many species in fact only lived for a few thousand years.

This natural asset is part of the tour "Browsing through the rocks of the Secëda mountain".

Along with few other molluscs, the bivalve genus Claraia is among the organisms that best adapted to the critical environmental conditions of the coastal sea waters after the extinction event taking place 252 million years ago. Remains of other organisms are only occasionally found in association with Claraia, showing just how extreme the environment was. It was apparently the only one surviving under these conditions.

This natural asset is part of the tour "Browsing through the rocks of the Secëda mountain".

This fossil fish is unique. Thanks to the microfossils contained in the rock, it could be dated back to the Permian-Triassic extinction event (about 252 million years ago). This was a crucial moment in the Earth's history, when life itself was threatened with extinction. Archaeolepidotus represents the Parasemionotiformes, which were already around in the Late Permian and then underwent extensive development in the Early Triassic. The majority of today's fish originate from this group.