We present the floristic composition and reproductive phenological data for a remnant of Arborized Stepic Savanna, vegetation type of humid Chaco, Porto Murtinho, Mato Grosso do Sul State, Brazil. We recorded 87 species of 31 families; Leguminosae presented the highest richness (14 species), followed by Malvaceae (9), Cactaceae (7) and Asteraceae (7). The herbaceous layer is relevant in the seasonal studied community (53.5% of the species) and there is predominance of non-perennial species (hemicryptophytes and therophytes), which demonstrate the importance of underground structures or seed banks in the vegetation. The community has continual flowering and fruiting with highest intensity in the rainy season, the most favorable period for plant growth and reproduction. The predominance of autochoric species in relation to anemochoric and zoochoric ones suggests partial independence of seed/fruit dispersal agents. Zoochorous species predominated in the rainy season, whereas anemochorous and autochorous species were more representative in the dry season.

The Brazilian Pantanal is an extensive wetland with heterogeneous habitats, primarily due to the riverfloodplain system and plants with differential adaptations and reproductive strategies. Factors such as altitude, distance among plant formations, and flood pulse must be considered to better understand its diversity. Aiming to assess the influence of biogeographic patterns in this system, we analyzed the floristic composition of six areas along the Paraguay River, including residual relieves, verifying the pattern of similarity, and effects of distance and altitude. We recorded 356 species in 87 families, mostly perennial (75%), and some annuals (15%) and pluriannuals (5%). Herbaceous plants were the most represented (48%), followed by arboreal (23%), shrubby (15%) and epiphytic (14%) habits, only 12% being endemic to Brazil. The studied areas showed low floristic similarity, but higher resemblance of species between neighboring areas, and no relation with altitude. The upper Paraguay River is diverse, with high spatial variability of species, predominantly perennial. The river-floodplain connectivity may be a determinant factor in species richness and occurrence of endemic species.

Prosopis L. is particularly rich and important in the Chaco region where forest vegetation currently persists as fragments. Its species are very important for the conservation and management of Chaco vegetation, and understanding their phenology and reproductive biology is essential. Here, we studied the phenology and pollination biology of P. rubriflora Hassl. in the Brazilian Chaco compared to other species of the genus. Differing from other Prosopis species, P. rubriflora is evergreen, and most phenophases are nonseasonal and bimodal (except fruiting), with a continuous pattern. Prosopis rubriflora is andromonoecious, but only weakly, since plants produce relatively few staminate flowers. Flowers showed three floral stylar phenotypes: short, medium and long style. Short-style flowers are functionally staminate because the stigma is nonreceptive. To compensate for the small size of P. rubriflora red brush flowers, attraction is compressed and transferred to the spike, which functions as a collective pollination unit. This compression may favour self-and intraplant pollination, which may reduce and/or prevent the occurrence of protogyny and partial, i.e. temporal, herkogamy in hermaphrodite flowers. Prosopis rubriflora has generalist pollination, but differs from the other Prosopis species because it is also pollinated by hummingbird, most likely due to its ''ornithophilous'' characteristics. This species is the first of the genus recorded as pollinated by hummingbirds. Although the exotic bee Apis mellifera L. presents high frequency of visit, this bee is not effective pollinator, due to its foraging style that does not favour cross-pollen flow. Native insects and hummingbird species are main pollinators because they present trapline foraging.

Germinating dynamics and seedling production of Cordia trichotoma (VELL.