Updated floristic biodiversity of Roman iconography.

Relatively little research has been carried out in the field of iconography in ancient Roman sculpture and painting. Therefore, we have compiled a botanical database to define the qualitative and quantitative aspects of botanical elements found in archaeological structures, and to name taxa cited in ancient literary sources which are of uncertain identification. This includes data set of about 420 art works and 3,000 related images based on information found in ancient writers and new discoveries, which have emerged from the research process. 202 taxa of plants (78 families, 159 genera, and 168 species) have been identified to date, and the main characteristics of their floristic elements and their degree of rarity are reported. Acanthus mollis, Vitis vinifera, Phoenix dactylifera, Punica granatum, Ficus carica, Laurus nobilis, and Hedera helix proved to be the species represented most frequently, due to their strong association with mythological and religious symbolism. The database contains 97 (47.8 %) new or very recently identified species, representing almost half of the information currently available in academic literature; a large proportion of species represented in the artworks (70.0 %) seems to occur with very low frequency. A number of doubtful exotic taxa attributed to Pompeian gardens in some previous iconographic studies have probably been confused with native species. The database confirms the wide variety of botanical elements and their frequent recurrence in ancient Roman decorations. The ancients' extensive knowledge of their natural surroundings is also confirmed, suggesting the need for a more wide-reaching cataloguing of archaeological structures.