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

THALIA/MARANTACEAE 737
pollen presentation—according to Kennedy (2000b), “Pollen is shed onto the back of the style
behind the stigma during the evening prior to anthesis. When the style, held under tension, is
released by the pollinator, the stigma moves forward scooping the pollen from the pollinator
and, in the same motion, depositing its own pollen in the same place.” The Marantaceae appears
monophyletic and is most closely related to the Cannaceae (CANNA family), more distantly to
the Zingiberaceae (GINGER family) and Costaceae (SPIRAL-FLAG family), and more distantly still
to other Zingiberales families, including the Heliconiaceae (HELICONIA family), Musaceae (BA-
NANA family), and Strelitziaceae (BIRD-OF-PARADISE family) (Smith et al. 1993; Chase et al. 2000;
Kress et al. 2001). Family name from Maranta, ARROWROOT or PRAYER-PLANT, a tropical American
genus of ca. 20 species. Maranta arundinacea L., WEST INDIAN ARROWROOT, has a starchy
edible rhizome, the starch (arrowroot) being easily digested and used for infants and invalids.
(Named for Bartolommeo Maranti, 16th century Venetian botanist and physician) (subclass
Zingiberidae—Cronquist; order Zingiberales—APG II)
FAMILY RECOGNITION IN THE FIELD: the only East TX species is a large rhizomatous herb with
broad, banana leaf-like leaves with a “joint” (pulvinus) where the long petiole and blade join;
inflorescences usually white-powdery; flowers purple; androecium of a single fertile stamen
and often staminodes.
REFERENCES: Andersson 1976, 1981b, 1998; Grootjen 1983; Kirchoff 1983, 1991; Rogers 1984;
Dahlgren et al. 1985; Kress 1990; Kirchoff 1991; Smith et al. 1993; Kennedy 2000a, 2000b;
Andersson & Chase 2001; Kress et al. 2001.
THALIA L. ALLIGATOR-FLAG
AA mostly tropical American (1 in Africa, presumably naturalized from the New World) genus
of 6 species of emergent aquatics (Kennedy 2000a). Fruit dispersal in Thalia is thought to
be most commonly by water—an air-filled space between the fruit wall and seed is reported to
make the fruit buoyant (Grootjen 1983; Kennedy 2000a). (Named either for Johann Thal, a German
physician and naturalist who died in 1583 or possibly for Thalia, one of the nine Greek
muses and the one who presided over comedy—Austin 2002)
REFERENCES: Davis 1987; Andersson 1981a.
Thalia dealbata Fraser ex Roscoe, (white-washed), POWDERY THALIA, POWDERED THALIA, POW-
DERY ALLIGATOR-FLAG. Perennial, emergent, aquatic herb 1–2.5 m tall from strong rhizomes, glabrous
and with whitened surfaces; leaves 2–5, long-petioled, alternate, all basal, large, banana
leaf-like; leaf blades 30–55 cm long, to 22 cm wide, ovate-lanceolate, pilose at very base on upper
(= adaxial) surface, with prominent midrib and numerous, curved side veins parallel with
each other, with a colored (yellowish brown to purple-brown to reddish) pulvinus at junction
with petiole; petioles to 80 cm long, the base winged and clasping; inflorescence a rather small
loose panicle, the axes zigzag in appearance, with whitish surfaces, with a prominent basal
bract paired with a small one, the bracts typically with conspicuously whitened surfaces; flowers
small, usually paired and enclosed by two bracts, sessile; sepals 3, 2.5 mm or less long; petals
3, unequal, purple, 5–10 mm long; fertile stamen 1; staminodes present, petal-like, purple,
united, one with cupped, projecting apex exceeding the petals; pistil 1; ovary inferior; fruit a
bluish purple, subglobose utricle 9–15 mm in diam. Shallow water, ditches, pond margins, or
other wet areas; mainly Pineywoods, Post Oak Savannah, and n Gulf Prairies and Marshes w to
Blackland Prairie (Dallas Co.—BRIT, Gonzales Co.—Turner et al. 2003); also escaping cultivation
in Tarrant Co. (Fort Worth Botanic Garden—BRIT) in the Cross Timbers and Prairies; se U.S.
from SC w to OK and TX, also IL and MO. May–Sep. This species is usually autogamous (= selfpollinating)
(Kennedy 2000a). It is sometimes grown as an ornamental. According to Kennedy
(2000a), this is “the only species of Marantaceae endemic to North America.” m/302