Araceae Juss. from Serra da Tiririca, Rio de Janeiro, Brazil

The study was conducted in Serra da Tiririca, located on the municipalities of Niterói and Maricá, in the state of Rio de Janeiro. It is part of Serra da Tiririca State Park, which protects 3,514 ha of Atlantic Forest. It is characterized by the Submontane Dense Ombrophylous Forest and vegetation on rocky outcrops in inselbergs. The objective was to inventory the native Araceae species occurring in Serra da Tiririca, indicate the preferred environments where the species are found, point out the presence of exotic species, and conservation measures. The collected material was registered in the RFFP herbarium, with duplicates in RB. 34 species were recorded, classified into 12 genera. Among these, Philodendron and Anthurium stood out, each represented by 11 species. Asterostigma and Thaumatophyllum presented two species each and Caladium, Heteropsis, Landoltia, Lemna, Monstera, Pistia, Syngonium and Wolffia, one species each. Anthurium lucidum, Anthurium luschnathianum, Philodendron hatschbachii and Philodendron nadruzianum are threatened with extinction. 12 species are considered new occurrences. Exotic species considered invasive are present in the areas, one terrestrial and three hemiepiphytes. The conservation of Araceae is threatened by urban expansion, deforestation, intense tourism, climbing and rappelling on inselbergs, wildfires, invasive species, and the collection of ornamental plants.