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

494 COMMELINACEAE/TINANTIA
TINANTIA Scheidw. FALSE DAYFLOWER, WIDOW’S-TEARS
AA genus of ca. 14 species (Faden 2000b) from TX to the American tropics; some are cultivated
as ornamentals. Two of the species (including T. anomala) were previously treated as
Commelinantia. Faden (2000b) suggested that “…although some attributes, including pollen
and chromosome number, can still be used to separate Commelinantia from Tinantia, these
characters are not of sufficient import to merit separate generic status.” (Named for François A.
Tinant, 1808–1858, a forester in Luxembourg—Faden 2000b)
REFERENCES: Tharp 1922, 1956; Woodson 1942; Castro 1978; Simpson et al. 1986.
Tinantia anomala (Torr.) C.B. Clarke, (anomalous), FALSE DAYFLOWER, WIDOW’S-TEARS. Tufted
glabrous annual with erect or spreading stems 2–80 cm long, becoming freely branched, the
branches emerging through the back of the leaf sheaths just above the nodes; basal leaves tapered
to a long petiole; upper stem leaves sessile or short petioled, the blades � lanceolate, often
somewhat cordate and clasping basally; flowers in elongate cymes; bract subtending inflorescence
flat, not folded, 4–8 cm long, similar to upper stem leaves but shorter and wider; petals
not clawed, the 2 upper and larger ones 15–18 mm long, lavender-blue, the much smaller lower
1 white; stamens 6, all fertile, very polymorphic; upper 3 stamens with filaments conspicuously
bearded with yellow-tipped hairs and with small anthers, the 2 lateral upper stamens upright,
the middle upper stamen less upright; lower 3 stamens curved downward, with larger anthers,
the filaments of lateral 2 lower stamens with purple hairs, the filament of middle lower stamen
glabrous; capsules 6–8 mm long. Limestone gravel or rocky crevices, often in some shade; Edwards
Plateau and Gulf Prairies and Marshes n to s part of Cross Timbers and Prairies and e to
Burleson Co. (along Koontz Bayou, near the Brazos River—TAMU); endemic to TX or nearly so (1
record from Durango, Mexico—R. Faden, pers. comm.). Apr–Jun, rarely later. [Commelinantia
anomala (Torr.) Tharp] Simpson et al. (1986) gave detailed information on the reproductive biology
of this apparently largely self-pollinating species. Nonetheless, Faden (2000c) reported
that the pollen sacs and hairs of the upper stamens absorb UV light, in contrast to the rest of
the flower. The anthers of these stamens have only half as much pollen as those of the other
stamens (Simpson et al. 1986). Pollinators (bees) are thus potentially deceived—they would obtain
less reward from the more attractive stamens (Faden 2000c). E? m/303
TRADESCANTIA L. SPIDERWORT, WANDERING-JEW
Perennial subsucculent herbs; leaf blades linear to oblong-elliptic; inflorescences subtended by
a usually leaf-like bract; petals equal, usually not clawed, blue to rose, magenta, purple, or
white; stamens 6, all fertile and equal; filaments long-pilose with colored hairs (glabrous in 1
species); anthers dumbbell or bow-tie shaped.
AAn American genus of ca. 70 species (Faden 2000b). A number are cultivated as ornamentals,
including species previously treated in Rhoeo (BOATFLOWER, OYSTERPLANT), Setcreasea, and
Zebrina (WANDERING-JEW). The staminal filaments of most species have long moniliform (=
made up of a row of single cells, like the beads of a necklace) hairs and were used by Robert
Brown in 1828 to observe and describe protoplasmic streaming (= the active flowing of cytoplasm
in the cell), which is easily observed under a microscope (Cochrane & Iltis 2000). Hybridization
and introgression are well known in Tradescantia and complicate the taxonomy of
the genus (Anderson & Woodson 1935; Anderson & Hubricht 1938; Faden 2000b). We are in
general following the traditional delimitation of species formulated by Anderson and Woodson
(1935) and followed by most authors since that time. Faden (2000b) indicated that, “The species
described by E. Anderson and R.E. Woodson Jr. (1935) are narrowly defined and typological.
Nevertheless, they are recognizable entities even if some of them may prove eventually unworthy
of specific rank.” The common name is possibly derived from the long slender leaves which
clasp the stem and dangle like spider legs or from the mucilaginous sap stringing out of a broken
stem to resemble a spider’s web, and “wort,” from Anglo-Saxon, wyrt, a plant or herb (Tveten