Saururaceae - Species Plantarum Programme

SPECIES PLANTARUM —FLORA OF THE WORLD 2005
1. SAURURUS
Saururus L., Sp. Pl. 1: 341 (1753)
Type: Saururus cernuus L.
Spathium Lour., Fl. Cochinch. 217 (1790). T: Spathium chinense Lour.
Mattuschkia J.F.Gmel., Syst. Nat., 13th edn [bis] 2: 589 (1791), non Mattuschkaea Schreb. (1791).
T: Mattuschkia aquatica (Walter) J.F.Gmel.
Saururopsis Turcz., Bull. Soc. Imp. Naturalistes Moscou 21(1): 589 (1848). T: Saururopsis chinensis
(Lour.) Turcz.
Herbs, erect or ascending, rhizomatous. Stems longitudinally ridged and sulcate. Leaves:
stipules membranous; petiole shorter than lamina; lamina entire, with 5–7 basal nerves.
Inflorescence a raceme, leaf-opposed and/or terminal, without involucral bracts; rachis
pubescent. Flowers 100–350, small, white when mature, with elongate flower-bract stalk
(“pedicel” see Liang & Tucker, 1990). Stamens usually 6, sometimes 8, rarely 3, free, longer
than styles; filaments c. as long as or slightly longer than anthers; anthers oblong. Pistils 4 or
1, 3 or 4 (–7)-carpellate, with carpels distinct or connate at base; ovary superior; each carpel
with 2–4 ovules; styles 4 or 1, recurved. Fruit a schizocarp; mericarps 3 or 4, indehiscent.
Seed 1 per mericarp.
Two species, distributed disjunctly in E North America and E Asia.
T.Holm, Saururus cernuus L. A morphological study, Amer. J. Sci., ser. 5, 12: 162–168
(1926); S.C.Tucker, Floral development in Saururus cernuus (Saururaceae). 1. Floral
initiation and stamen development, Amer. J. Bot. 62: 993–1007 (1975); S.C.Tucker, Floral
development in Saururus cernuus (Saururaceae). 2. Carpel initiation and floral vasculature,
Amer. J. Bot. 63: 289–301 (1976); S.C.Tucker, Ontogeny of the inflorescence of Saururus
cernuus (Saururaceae), Amer. J. Bot. 66: 227–236 (1979).
Racemes nodding to erect; floral bracts green; leaf petioles to 10 cm long;
stamens hypogynous, filaments 3–4 mm long (North America)
Racemes not nodding, floral bracts white; leaf petioles to 3 cm long; stamens
epigynous, adnate to lower part of ovaries, filaments c. 1 mm long (Asia)
1. Saururus cernuus L., Sp. Pl. 1: 341 (1753)
1. S. cernuus
2. S. chinensis
T: [U.S.A., Virginia], "Habitat in Marilandia, Virginia"; lecto: Herb. Linn. 478.1, LINN, fide J.L.Reveal et al.,
Huntia 7: 234 (1987).
Mattuschkia aquatica (Walter) J.F.Gmel., Syst. Nat., 13th edn [bis] 589 (1791); Saururus aquaticus Walter,
Fl. Carol. 127 (1788). T: not designated.
Saururus lucidus Donn, Hortus Cantabrig., 3rd edn 66 (1804). T: [U.S.A.], Sep. 1791, s.coll.; holo: n.v.
Saururus cernuus L. f. submersus Glück, Biol. Morphol. Untersuch. Wasser-Sumpfgewächse 3: 69, t. 3 (1911).
T: not designated, cultivated.
Illustrations: H.X.Liang & S.C.Tucker, Amer. J. Bot. 77: 609, 612 (1990); L.Watson & M.J.Dallwitz, Fam. Fl.
Pl., http://delta-intkey.com (1992–).
Map: G.F.Buddell & J.W.Thieret, Saururaceae, in Fl. N. America N. Mexico 3, Magnoliophyta: Magnoliidae
and Hamamelidae 38 (1997).
Herbs 15–120 cm high, mostly pubescent when young, often glabrate; rhizome extensive,
stout, whitish, often with adventitious roots. Leaves: stipule sheath 2–10 mm long, slightly
clasping; petiole 1–10 cm long; lamina ovate or cordate, 2–18 × 1–10 (–15) cm, cordate
at base, acuminate, papery, with 5–7 nerves. Racemes terminal and/or leaf-opposed, nodding
to erect, narrow, (4–) 5–35 cm long; peduncle 2–15 mm long. Bract beneath each flower
adnate to pedicel, navicular, 1.5–3 mm long (distinct portion), green. Stamens hypogynous,
3–4 mm long. Fruit 1.5–3 mm long, rugose. 2n = 22, fide H.Okada, Bot. Mag. (Tokyo) 99:
289–299 (1986).
Eastern Canada to C and E USA; introduced in Germany and Italy. 11: GER. 13: ITA.
72: ONT, QUE. 74: ILL, KAN, MSO, OKL. 75: CNT, INI, MIC, NWJ, NWY, OHI, PEN,
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