Ludwigia L. sect. Jussiaea (L.) Hoch, W.L.Wagner, & P.H.Raven 2015

Hoch, Peter C., Wagner, Warren L. & Raven, Peter H., 2015, The correct name for a section of Ludwigia L. (Onagraceae), PhytoKeys 50, pp. 31-34 : 33-34

Ludwigia L. sect. Jussiaea (L.) Hoch, W.L.Wagner, & P.H.Raven comb. nov.

Jussiaea L., Sp. pl. 1: 388. 1753. [ Jussia Adans., Fam. 2: 85, 565. 1763, orth. var.]; Jussiaea L. sect. Eujussiaea Munz, Darwiniana 4: 184. 1944. Type. Jussiaea repens L. [= Ludwigia adscendens (L.) H.Hara] (Lectotype, designated by Hitchcock & Greene, Prop, Brit. Bot. 153. 1929).

Jussiaea L. sect. Oligospermum Micheli in Martius, Fl. bras. 13(2): 149, 162. 1875. Ludwigia L. sect. Oligospermum (Micheli) H.Hara, J. Jap. Bot. 28: 290. 1953. Type. Jussiaea hookeri Micheli [= Ludwigia hookeri (Micheli) H.Hara] (Lectotype, designated by Raven, Reinwardtia 6: 335. 1963).

Cubospermum Lour., Fl. Cochinch. 258, 275. 1790. Type. Cubospermum palustre (L.) Lour. [= Ludwigia adscendens (L.) H.Hara].

Adenola Raf., Aut. Bot. 36. 1840. Type. Adenola grandiflora (Michx.) Raf. [= Ludwigia grandiflora (Michx.) Greuter & Burdet]. (Lectotype, designated by Pennell, Bull. Torrey Bot. Club 48: 93. 1921).

Oocarpon Micheli, Flora 57: 303. 1874. Ludwigia sect. Oocarpon (Micheli) P.H.Raven, Reinwardtia 6: 336. 1963. Type: Oocarpon jussiaeoides Micheli [= Ludwigia torulosa (Arn.) H.Hara].

Description.

Perennial herbs, stems creeping, floating, or emergent and ascending to erect, rooting at nodes, when floating often forming spongy white pneumatophores at nodes, when erect with spongy base, terete. Leaves alternate; blades with one submarginal vein. Flowers 5(6)-merous; petals present, yellow or white; stamens twice as many (rarely as many) as sepals, pollen shed in monads. Capsules cylindrical, terete, often curved up, woody with thick walls, irregularly and tardily dehiscent. Seeds in one row per locule, pendulous, and firmly embedded in a woody coherent segment of endocarp, with inconspicuous raphe. 2n = 16, 32, 48, 80, 96.

Taxa included.

Ludwigia adscendens (L.) H.Hara, Ludwigia grandiflora (Michx.) Greuter & Burdet, Ludwigia helminthorrhiza (Mart.) H.Hara, Ludwigia hexapetala (Hook. & Arn.) Zardini, H.Y.Gu & P.H.Raven, Ludwigia hookeri (Micheli) H.Hara, Ludwigia peduncularis (C.Wright ex Griseb.) M. Gómez, Ludwigia peploides (Kunth) P.H.Raven subsp. glabrescens (O. Kuntze) P.H.Raven, Ludwigia peploides subsp. montevidensis (Sprengel) P.H.Raven, Ludwigia peploides subsp. peploides , Ludwigia peploides subsp. stipulacea (Ohwi) P.H.Raven, Ludwigia stolonifera (Guill. & Perr.) P.H.Raven, Ludwigia torulosa (Arn.) H.Hara.