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

784 ORCHIDACEAE/SPIRANTHES
persisting until flowering but sometimes withering, usually short-petioled; leaf blades oblanceolate,
1–5.5 cm long, 0.75–1 cm wide; inflorescence with flowers single-ranked (sometimes 1sided)
to tightly spiraled and multi-ranked, essentially glabrous (when viewed with a hand
lens; when a dissecting scope is used, sparse, scattered capitate glands can be seen); perianth
white, 3–5 mm long; lip white with green center, without lacerate apex. Dry sandy pine barrens,
roadsides, cemeteries, dry pine flatwoods; Jefferson Co. (BRIT) near s margin of the
Pineywoods; se VA s to FL w to TX. Feb–May. This species was recently described as a new species
by Brown (1999) and, as such, is one of the more recent additions to the flora of East TX.
According to Sheviak and Brown (2002), this “is the only white-flowered, basal-leaved
Spiranthes within its range to bloom at that time of year [late winter to spring].” The “narrow
oblanceolate leaves” are also “distinctive.” Known from only one county in TX, this species is of
conservation concern. � m/300
Spiranthes floridana (Wherry) Cory, (of Florida), FLORIDA LADIES’-TRESSES. Plant similar to S.
brevilabris, 7–40 cm tall; leaves 3–5, basal, present at flowering time; leaf blades usually ovate,
2–6 cm long; inflorescence 1-sided (= secund) to loosely spiraled, glabrous or with only sparse
hairs; perianth cream to yellowish white or yellowish green, to ca. 5 mm long; lip with yellow
center. Open pinelands and meadows; Hardin, Jefferson, and Tyler (Liggio & Liggio 1999) cos. in
the Pineywoods; also Harris Co. (Liggio & Liggio 1999) in the Gulf Prairies and Marshes; Liggio
and Liggio (1999) indicated that this taxon is known from only five herbarium collections from
TX; AL, FL, GA, MS, NC, SC, and TX. Feb–May. [Imbidium floridanum Wherry, S. brevilabris
Lindl. var. floridana (Wherry) Luer, S. gracilis (Bigelow) L.C. Beck var. floridana (Wherry)
Correll] This species has sometimes been treated as a variety of S. brevilabris (e.g., Hatch et al.
1990; Liggio & Liggio 1999) or not recognized as distinct from that species (Turner et al. 2003),
and the two “are often and easily confused, although the degree of pubescence is an excellent
diagnostic tool in the field” (Sheviak & Brown 2002)—S. brevilabris has the inflorescence
densely pubescent, while in S. floridana it is glabrous or with only sparse pubescence. While
we are following Sheviak and Brown (2002) in treating this taxon as a distinct species, further
research is warranted to determine the most appropriate rank at which to recognize the variation
present. As with S. brevilabris, Sheviak and Brown (2002) reported that “This species has
become very uncommon, with only a single extant population known in 1998–2000.” However,
J. Liggio (pers. comm.) is aware of populations in two units of the Big Thicket National Preserve.
Nevertheless, while not officially recognized as such (e.g., TOES 1993; Carr 2002d; Poole et al.
2002), we consider this rare species to be of conservation concern. � m/300
Spiranthes lacera (Raf.) Raf. var. gracilis (Bigelow) Luer, (sp.: torn; var.: graceful), SOUTHERN SLEN-
DER LADIES’-TRESSES, SLENDER LADIES’-TRESSES, GREEN-LIP LADIES’-TRESSES, AUTUMN TRESSES. Plant
essentially glabrous, 20–60 cm tall; leaves all basal, usually not persisting until flowering, short
petioled; leaf blades ovate, 1.5–6.5 cm long, 10–25 mm wide; inflorescence with flowers singleranked,
1-sided to loosely or � densely spiraled; perianth white, ca. 5 mm long; lip white
marked with broad green or yellow-green stripe or spot in center, the apex finely lacerate.
Sandy woods, prairies, often as a “pioneer” species in abandoned farmland and old fields (Liggio
& Liggio 1999); widespread in East TX; also Denton Co. (Liggio & Liggio 1999) in the East Cross
Timbers and n Gulf Prairies and Marshes; se Canada (Ont.) and throughout e U.S. w to MI and
TX. Sep–Nov. [S. gracilis (Bigelow) L.C. Beck] Hybrids are known between this taxon and S.
vernalis (Sheviak & Brown 2002). The more n S. lacera var. lacera, which does not reach TX,
can be distinguished by the inflorescence with capitate pubescence and the leaves usually persisting
through flowering time (Sheviak & Brown 2002). m/300
Spiranthes laciniata (Small) Ames, (laciniate, torn, in reference to the edge of the lip), LACE-LIP
LADIES’-TRESSES, FRINGE-LIP LADIES’-TRESSES, LACE-LIP SPIRAL ORCHID. Plant 20–60(–100) cm tall;
leaves persisting through flowering time, linear-lanceolate, 5–25(–40) cm long, to 1(–1.7) cm
wide; inflorescence pubescent with capitate hairs, the flowers single-ranked, loosely spiraled to