keys to the vascular plants of east texas - Botanical Research ...

740 MELANTHIACEAE/SCHOENOCAULON
5. Tepal bases not clawed, only gradually and slightly narrowed at base; gland at tepal
bases lacking or obscure; bracts 2–5(–12) mm long; bulb slender, � cylindrical; filaments
slender their whole length or nearly so; plants of forests, forest margins, damp pinelands,
and bogs _______________________________________________________________ Stenanthium
5. Tepal bases (at least the inner ones) abruptly narrowed and claw-like at base; gland at tepal
bases present; longest bracts usually 10–20 mm long; bulb ovoid; filaments widened at
base; plants of prairies and open woods, often on calcareous substrates ___________ Toxicoscordion
SCHOENOCAULON A. Gray
SABADILLA, FEATHER-SHANK, GREEN-LILY, CEBADILLA
Herbaceous, scapose perennials with a much reduced rhizome terminating in a fibrous-tunicate
bulb (with dark scales and fibers); leaves all basal, grass-like, glabrous, marginally serrulate;
scapes naked, erect, unbranched; inflorescences spicate, terminal, many-flowered (bottlebrush-like);
flowers sessile or sub-sessile, perfect (staminate at apex of inflorescence), each
subtended by a small bract; tepals 6, � equal, essentially free, pale green or greenish white, persistent;
stamens 6 in 2 whorls, 2–2.5 times as long as perianth; styles 3, distinct; ovary superior;
fruit a 3-celled capsule, ca. 1–2 cm long.
AA New World genus of 10–25 species (Frame 2002) native from the s U.S. to Peru, with most
species endemic to Mexico (Frame 1989). It is distinguished from related genera by its spikelike,
racemose inflorescence of small flowers with exserted stamens (Frame 2001). Delimitation
of species has been difficult (Zomlefer 1997a), and the exact number of species has been
variously estimated to be 10–25 (Frame 1989, 2002; Zomlefer 1997a; Tamura 1998b); Zomlefer
and Judd (2002) estimated 24 species. Recent molecular as well as morphological evidence suggests
the genus is monophyletic (Zomlefer et al. 2001). According to Frame (2002), “Schoenocaulon
has rarely been collected in the United States in recent times; all three [U.S.] species are
possibly threatened.” However, Zomlefer (pers. comm.) notes that S. dubium (Michx.) Small of
FL is common. Frame (1989) indicated that “… the perianth more or less i[e]ncloses the
androecium at anthesis. After anthesis, the perianth opens and elongates somewhat, and the
filaments elongate relatively more than the perianth.” � Some species have Veratrum-type
cerveratrum alkaloids (e.g., sabadine and veratradine); S. officinale A. Gray (SABADILLA, CEVA-
DILLA) has seeds that are insecticidal and have been used by humans (e.g., louse powder) and in
veterinary medicine as a topical pesticide (Kupchan et al. 1961; Mabberley 1997; Zomlefer 1997a;
Frame 2002). “An extract of sabadilla reportedly was one of the ingredients in the asphyxiating
gases used by the Germans in chemical warfare of World War I” (Zomlefer 1997a). (Greek:
schoeno, reed or rush-like, and caulos, a stalk, in reference to the naked scape—Frame 1989, or
the rush-like appearance of the inflorescence of tiny flowers—Zomlefer 1997a)
REFERENCES: Brinker 1942; Frame 1989, 1990, 2001, 2002; Frame et al. 1999; Zomlefer et al. 2001.
1. Plants usually (but not always) flowering in autumn (Sep–Oct); tepals usually elliptic to ovateelliptic,
submembranous to slightly fleshy, with thin crenulate to minutely denticulate margins;
inflorescences 15–20 mm in diam. _______________________________________________ S. ghiesbreghtii
1. Plants flowering in spring and summer (Mar–Jul, rarely later after unseasonable rainfall); tepals
linear-oblong, fleshy-thickened or almost leathery, with thickish entire margins; inflorescences
10–15 mm in diam. _______________________________________________________________ S. texanum
Schoenocaulon ghiesbreghtii Greenm., (for A.B. Ghiesbreght, 1810–1893, who collected the type
in Chiapas, Mexico), GREEN-LILY, DRUMMOND’S SABADILLA, GREEN FEATHER-SHANK. Plant to ca. 90
cm tall; leaves to 50(–75) cm long, to 7(–11) mm wide; tepals ca. 2.5–4.7 mm long, pale green; 2n
= 16 (Frame 2002). Sandy or gravelly soils, roadsides, arroyos, prairies, forest margins, caliche;
Bastrop, Colorado, Gonzales, Guadalupe (BRIT), Bexar, Caldwell, DeWitt, Fayette, and Wilson
(Turner et al. 2003) cos. in s part of Post Oak Savannah; also Gulf Prairies and Marshes and