ABSTRACT:

The 28 species of the genus Arum (Araceae) attract and temporarily trap insects (mainly flies, and beetles in a few cases) during a complex pollination process. At anthesis, the appendix of the inflorescence produces heat and emits a specific odor which attracts insects. The lured insects are trapped within the floral chamber when stigmas are receptive. They will be released about 24h later after pollen emission, ensuring pollen dissemination. Studies on the reproductive biology of the genus have shown some degree of variability in the pollination strategies: morphological variations, flowering and heating periods, odor types and the type of pollinating insects. Most species of Arum have never been studied in depth but data available from the literature indicate quite a high diversity of pollination strategy within this genus. Consequently, a general pollination model is not valid at the level of the whole genus. The origin of this diversity certainly results from the biogeographic history of the genus. The plants (Le. species) have developed adaptations in response to different climatic, ecological and biotic (i.e. entomofauna) constraints (Le. selective pressures) according to the various habitats occupied in the different regions of Europe and the Middle East. However, in the absence of phylogenetic data, it is actually impossible to determine how these different reproductive strategies have developed and evolved during the history of this genus.