Cristina Lombardo

Abstract: The ichthyofauna of the Zorzino Limestone represents an important step in the biodiversity of the bony fishes. With its richness and variety at the highest point of the Triassic, this fauna also testifies to the beginning of the faunal transition that will be realized during the Jurassic. Thousands of specimens and extraordinary preservation of the fossils yielded by these levels have allowed the monitoring of such a crucial moment in the evolution of vertebrates. These favourable conditions allowed also the reconstruction of the mode of life and the trophic adaptations performed by the different fish groups that dwelled in those depositional basins surrounded by the largest carbonate platform ever, now known as the Dolomia Principale (or Haupt Dolomite of German-speaking geologists). As further proof of this peculiar evolutionary period, the large predators occupying the highest trophic levels were still represented by ‘primitive’ basal actinopterygians; on the contrary, the most derived neopterygians developed a specialization in durophagy, a trophic niche formerly unexploited by actinopterygians. Within the main trophic categories, we can find different morphological specializations, which probably allowed the fishes to exploit most of the available trophic resources. The blooming of the stemgroup Teleostei, the Pholidophoriformes, is also recorded, with several genera occurring together in the best represented localities.

TL;DR: The most complete and articulated postcranial skeleton for an adult B. liui from the early Late Ladinian of South China was reported in this article, which showed the number of neural arches and their changes along the vertebral column, the articulation between the neighboring haemal spines in the caudal region, presence of ribs, the endoskeleton and the pattern of lepidotrichia of all fins and the covering of scales.