Sagittaria

  • Authority

    Haynes, Robert R. & Holm-Nielsen, Laurtiz B. 1994. The Alismataceae. Fl. Neotrop. Monogr. 64: 1-228. (Published by NYBG Press)

  • Family

    Alismataceae

  • Scientific Name

    Sagittaria L.

  • Type

    Type species. Sagittaria sagittifolia L. Name from the Latin, sagitta, an arrow.

  • Synonyms

    Lophotocarpus, Lophotocarpus guayanensis (Kunth) Griseb., Sagittaria guayanensis Kunth

  • Description

    Genus Description - Plants monoecious or rarely dioecious, perennial or rarely annual, glabrous to sparsely pubescent, submersed, floating-leaved, or emersed in fresh or brackish waters. Roots septate. Stems often with rhizomes, the rhizomes occasionally terminated by tubers, the tubers brown, smooth. Leaves submersed, floating, or emersed, entire, sessile or petiolate, the petioles terete to triangular, the blades present or absent, with or without basal lobes, without pellucid markings. Inflorescence a racemose, paniculate, or rarely umbelliform scape of 1-17 whorls, the whorls with 2-3 flowers, erect, emersed or floating, rarely submersed, the bracts coarse or delicate, smooth to papillose, obtuse to acute, the flowers staminate above and carpellate below. Flowers imperfect, rarely the lower with a ring of sterile stamens, pedicellate; pedicels elongating after anthesis, ascending to recurved; sepals herbaceous to coriaceous, often sculptured, reflexed in staminate flowers, reflexed to appressed in carpellate flowers; petals white or rarely with a pink to purple spot or tinge; androecium of 7-many stamens, the anthers basifixed, linear to orbicular, the filaments linear to dilated, glabrous to pubescent; gynoecium of many carpels, the carpels spirally arranged, 1-ovuled, the styles terminal. Achenes compressed, numerous, often laterally winged, ecostate, glandular, with a conspicuous dorsal wing.

  • Discussion

    Bogin (1955) combined Sagittaria and Lophotocarpus, recognizing 2 subgenera, subgenus Sagittaria and subgenus Lophotocarpus. The two subgenera can be separated by subgenus Sagittaria having ascending to reflexed sepals and mostly spreading to ascending pedicels in fruit, and all flowers imperfect, whereas subgenus Lophotocarpus has appressed sepals and recurved pedicels in fruit, and the upper flowers perfect.

  • Distribution

    A predominantly Western Hemisphere genus of approximately 25 species, distributed from Canada south to Argentina and Chile. Three or four species also occur in Europe and Asia.

    North America| Central America| South America| Europe| Asia|