This work presents a survey of mosses from different ecosystems of Trambioca Island, municipality of Barcarena, Pará State, Brazil. Forty taxa of mosses were found, belonging to 20 genera and 13 families. The families with highest number of species were Calymperaceae (12 spp.), Sematophyllaceae (6 spp.), and Leucobryaceae (5 spp.), which also presented the highest number of individuals. The most common species were Sematophyllum subsimplex (Hedw.) Mitt, Calymperes erosum Müll. Hal., Pilosium chlorophyllum (Hornsch.) Müll. Hal., Callicostella pallida (Hornsch.) Årgstr., and Trichosteleum papillosum (Honrsch.) A. Jaeger. It was observed a higher richness of species in the primary low land rainforest, confirming the preference of bryophytes for this ecosystem. Philonotis gracillima Ångstr. is mentioned as the first report to Pará State.
Bryophytes; diversity; Philonotis gracillima Ångstr.; bryoflora
