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

748 NARTHECIACEAE
REFERENCES: Preece 1956; Kupchan et al. 1961; Zomlefer 1997a; Frame et al. 1999; Zomlefer et al.
2001; Schwartz 2002; Zomlefer & Judd 2002.
1. Plant from thickened, twisted rhizome; tepals (9–)10–16 mm long, each with 2 glands above
base ________________________________________________________________________ Z. glaberrimus
1. Plant from a bulb (this sometimes slender); tepals 3–8(–9) mm long, each with 1 gland at base or
gland lacking (species previously treated in Zigadenus)
2. Tepals 3–5 mm long, narrowed but not so abruptly as to be claw-like at base; filaments slender
their whole length; bracts 2–5(–12) mm long; plants of wet areas, damp pinelands, and
bogs ______________________________________________________________ see Stenanthium densum
2. Tepals usually (5–)6–8(–9) mm long, at least the inner ones abruptly narrowed and claw-like
at base; filaments widened at base; longest bracts usually 10–20 mm long; plants of drier
habitats, prairies and open woods, often on calcareous substrates ____________ see Toxicoscordion nuttallii
Zigadenus glaberrimus Michx., (very smooth, bare), SANDBOG DEATH-CAMAS, ATLANTIC DEATH-
CAMAS, SNAKE-ROOT, was apparently erroneously reported for “Tex. (?)” by Correll and Johnston
(1970) and for East TX (no county specified) by Nixon and Kell (1993). However, according to
Schwartz (2002), this species of the far se U.S. occurs in neither TX nor any adjacent state, and
she considers its closest occurrence to TX to be in MS. Likewise, we have seen no specimens
from TX and thus do not consider it to be a member of the East TX flora. It is included here to
clarify confusion and to alert collectors to its possible, but unlikely, occurrence in the state.
Bogs, savannahs, sandy pinelands; AL, FL, GA, MS, NC, SC, VA. Mid-Jul–Sep. This species, now
recognized as a monotypic genus, has long been recognized as unusual. For example, Radford et
al. (1968) suggested that it was unusual in having rhizomes, was “perhaps generically distinct”
from the other members of the genus, and was in “many respects very closely related to
Melanthium.” As with many other members of the Melanthiaceae, this species should be considered
toxic (Burrows & Tyrl 2001). �
NARTHECIACEAE Fr. ex Bjurzon
BOG ASPHODEL FAMILY
AA small family (4–5 genera, ca. 21–28 species) of perennial herbs, generally of temperate climates
from e Asia and Indomalaysia to e North America and n South America; a few have been
cultivated as ornamentals (Zomlefer 1997c; Caddick et al. 2002b). The genera have been variously
treated in terms of family affiliation. Many authorities (e.g., Correll & Johnston 1970;
Cronquist 1988; Diggs et al. 1999) have put them in a broadly defined and clearly polyphyletic
(but practical) Liliaceae, based on superficial similarities in flower structure to the genus
Lilium, while others have put them in a polyphyletic Melanthiaceae (e.g., Dahlgren et al. 1985).
We are using a narrower and presumably monophyletic circumscription following Zomlefer
(1997c) and Caddick et al. (2002b). Tamura (1998c) recognized the Nartheciaceae but treated
the family more broadly (10 genera and ca. 72 species), including genera here considered to
comprise the very distantly related Tofieldiaceae. Some authorities have recognized the family
in the order Nartheciales (Reveal & Zomlefer 1998). Preliminary molecular/cladistic evidence
suggested that the order Nartheciales (excluding the Tofieldiaceae) was in an isolated position
and appeared to be the sister group of the Dioscoreales (Chase et al. 1995a; Zomlefer 1999; Fuse
& Tamura 2000). Subsequently, a number of authorities (e.g., Caddick et al. 2000, 2002a,
2002b; Chase et al. 2000; APG II 2003) have placed the family in the Dioscoreales (the classification
we are following here). However, a very recent molecular study (Davis et al. 2004) suggests
that the Nartheciaceae is the sister group to the Pandanales. Whichever ordinal designation
is chosen, members of the Nartheciaceae are not closely related to other taxa often put in a
broadly defined Liliaceae. In addition, the Nartheciaceae are only distantly related to the