water-plantains (#Alismataceae) are a family of flowering plants, comprising 20 genera (17 extant and 3 fossil) and 119 species. The family has a cosmopolitan distribution, with the greatest number

The water-plantains (#Alismataceae) are a family of flowering plants, comprising 20 genera (17 extant and 3 fossil) and 119 species. The family has a cosmopolitan distribution, with the greatest number of species in temperate regions of the Northern Hemisphere. Most of the species are herbaceous aquatic plants growing in marshes and ponds.

Sagittaria guayanensis Kunth occurs in subtropical and tropical ponds and lakes around the world (paleotropic representatives might belong to a separate species, though). Along the Amazon coast, it is even found in seasonal roadside puddles. The species features both perfect and staminate, "male" flowers (with pollen-producing stamens but without carpels that develop into fruits).
#botany #Alismataceae #Amazonas #wetlands #flowers #pond #aquaticPlants

Another plant of the Amazon coast seasonal freshwater wetlands: Sagittaria rhombifolia Cham. Its long, narrow leaves can be easily mistaken for those of a sedge from a distance, but the white, showy flowers clearly indicate that it is not. I collected this plant for our herbarium – there are two older records (1955, 1977) from the same region in other collections, and I'm glad that the plants are still thriving here.
#Amazonas #Alismataceae #botany #herbarium #HBRA #BragançaPA #wetlands

Helanthium tenellum (Mart.) Britton is a widespread, small aquatic plant of seasonal ponds. It should be well-known to aquarium enthusiasts. Like many other plants in this type of habitat, it spreads vegetatively while covered by water and starts to flower when the pond dries out. Here along the Amazon coast, we find this species in coastal dune areas and white sand, savanna-like habitats.
#Alismataceae #aquaticPlants #Amazonas #aquarium #botany #flowers