An unusual form of forest with many large lianas at all levels is found on the higher land in the south and southeast of the ecoregion.

Large trees in the liana forests include Apuleia molaris, Bagassa guianensis, Caryocar villosum, Hymenaea parvifolia, Tetragastris altissima, Astronium graveolens, Astronium lecointei, Apuleia leiocarpa, Sapium marmieri, Acacia polyphylla, Elizabetha species, Brazil nut (Bertholletia excelsa) and mahogany (Swietenia macrophylla).

Common trees in eastern Pará that are not found to the west of the Tapajós include Zollernia paraensi, cupuaçu (Theobroma grandiflorum) and Cordia goeldiana.

The predominant white-sand igapó forest along the clearwater Tapajós holds species of the family Myrtaceae and trees such as Triplaris surinamensis, Piranhea trifoliata, Copaifera martii, Alchornea castaneifolia and Handroanthus heptaphyllus.

Other mammals are the red-bellied titi (Callicebus moloch), Azara's night monkey (Aotus azarae infulatus), white-cheeked spider monkey (Ateles marginatus), white-lipped peccary (Tayassu pecari), collared peccary (Pecari tajacu), cougar (Puma concolor), jaguar (Panthera onca), South American tapir (Tapirus terrestris), and brocket deer (Mazama genus).

[2] Endangered mammals include the white-cheeked spider monkey (Ateles marginatus), white-nosed saki (Chiropotes albinasus) and giant otter (Pteronura brasiliensis).

These include osprey (Pandion haliaetus), harpy eagle (Harpia harpyja), channel-billed toucan (Ramphastos vitellinus), little chachalaca (Ortalis motmot), nine tinamou species (genera Crypturellus and Tinamus), seven macaw species (genus Ara) including hyacinth macaw (Anodorhynchus hyacinthinus), many parakeets (genera Aratinga, Pyrrhura and Brotogeris), parrots (genera Amazona and Pionus) and the hoatzin (Opisthocomus hoazin).

[2] The Tapajós–Xingu, Xingu–Tocantins–Araguaia, and Tocantins–Araguaia–Maranhão moist forest ecoregions on the eastern edge of the Amazon basin have all been badly affected by human settlement and deforestation.

[6] Roads have opened the region to rapid and uncontrolled growth of colonies, logging, ranching and major projects that have destroyed large areas of forest and degraded the land.

[7] Global warming will force tropical species to migrate uphill to find areas with suitable temperature and rainfall.

[8] The Amazônia National Park protects both sides of the Tapajós near Itaituba, with an area of 9,935 square kilometres (3,836 sq mi), but it is underfunded.