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

ORONTIUM/ARACEAE
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down the inside of the [tubular] spathe, where they become trapped and pollinate the female
flowers” (Brickell & Zuk 1997). Ørgaard and Jacobsen (1998) have studied pollination in the
group and determined that the pollinators (flies) are attracted by a carrion-like odor. A further
elaboration of this “trap-escape mechanism” are down-pointing hairs inside the spathe which
prevent insects from climbing out before they have collected pollen from the later-maturing
male flowers. After the male flowers mature and the pollen is released, the hairs collapse, permitting
the insects to escape and thus carry out the pollen. Additionally, a thin layer of mucilage
on the inner surface of the lower part of the spathe (“kettle”) has been suggested as a food
source/reward for pollinators. Many species are cultivated as ornamental aquarium plants,
some are grown on a large scale for this purpose, and Cryptocoryne is one of the best known
aroid genera from an aquarist’s viewpoint (Bown 2000). The following description is slightly
modified from Nicolson (1987a) and Rosen (2000). (Greek: kryptos, hidden, and korynê, club,
the spadix being hidden from view inside the spathe—Mayo et al. 1997)
REFERENCES: Jacobsen 1976, 1977; Reumer 1984; Graaf & Arends 1986; Nicolson 1987a; Ørgaard
& Jacobsen 1998; Rosen 2000; Doyle 2001; Bastmeijer 2003.
Cryptocoryne beckettii Thwaites ex Trimen, (for T.W. Beckett, 1839–1906, a coffee planter who
collected plants in Sri Lanka), WATER-TRUMPET. Perennial, rhizomatous, emergent-submerged,
evergreen herb; leaves basal, with elongate sheathing petioles to 15 cm long; leaf blades glabrous,
ovate to narrowly ovate, 3–10(–15) cm long, (1–)1.5–3.5(–4) cm wide, the upper surface
green to dark green to brown and marbled to red-brown, the lower surface red-tinged to more
or less brownish or green, the veins usually conspicuously red or purplish, the apex acute to
acuminate, the base obtuse to cordate, the margins entire, sometimes undulate; submerged
specimens mostly with larger, thinner leaves, often brownish marbled; inflorescence (not seen
in TX material) short peduncled; spathe 4–13(–20) cm long, the limb greenish brown, narrowly
ovate, 0.5–1.2 cm wide, 1.5–3 cm long, upright to somewhat recurved and twisted; spadix 1 cm
long; 2n = 28, 42 (Reumer 1984). Exposed bottom in open shallow riffles and shaded deep pools
of the San Marcos River in the city of San Marcos; in TX known only from Hays Co. at extreme
w edge of East TX; reported as first collected in TX in 1996 (Rosen 2000); no other North
American records were reported by either Kartesz (1999) or Thompson 2000b—except for this
TX locality, the species is apparently unknown from North America. Data not available on
flowering in TX. Native of Sri Lanka (Jacobsen 1976). Rosen (2000) suggested that the occurrence
in the San Marcos River is probably the result of escape from cultivation or the dumping
of aquaria. This species has the potential to spread rapidly, and it poses a threat to Zizania
texana (TEXAS WILD RICE) (Doyle 2001), an endangered species which is known only from the
upper San Marcos River. Cryptocoryne beckettii should be designated as a noxious weed and is
symbolized as such here; Doyle (2001) recommends eradication while it is still possible. � I
ORONTIUM L. GOLDEN-CLUB
AA monotypic genus endemic to e North America. The common name derives from the golden
yellow spadix borne at the end of a scape. (Classical name for a water plant growing in the
Syrian river Orontes)
REFERENCES: Wilson 1960; Grear 1966; Klotz 1992.
Orontium aquaticum L., (growing in or under water), GOLDEN-CLUB. Aquatic perennial herb
with thick rhizomes buried in mud; leaves all basal, long-petioled (petioles to 40+ cm long); leaf
blades simple, oblong-elliptic, 6–30(–45) cm long, 3–16 cm wide, bluish green with distinctive
velvety sheen, cuneate at base, prominently parallel-veined, entire, emergent or often floating
(waxy and readily shedding water and with large intercellular air spaces); spadix on an elongated
scape, bright golden yellow, oblong, 2–5(–10) cm long, with a band of white below the
flowers; spathe apparently absent (actually a very small spathe is present at the insertion of