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

558 CYPERACEAE/CYPERUS
sexual (seed producing) and asexual (reproducing by rhizome propagation or formation of vegetative
plantlets in the spikelets) reproduction is known in the species (Miao et al. 1998). This
species has often been treated as a subspecies of the Old World C. mariscus (e.g., Kartesz 1999).
However, we are following Hatch et al. (1990), Jones et al. (1997), and Tucker (2002c) in treating
it as a distinct species. Tucker (2002c) recognized it as such “with some trepidation.”
Cladium mariscoides (Muhl.) Torr., (resembling Mariscus, a segregate now included in Cyperus),
SMOOTH SAW-GRASS, TWIG-RUSH, SWAMP SAW-GRASS. Plant 0.3–1 m tall; rhizomes ca. 2 mm in
diam.; leaf blades involute, with scaberulous margins; inflorescences 5–30 cm long, slender, ca.
2–5 cm wide, usually of relatively few cymes, the inflorescences much smaller than in C.
jamaicense, ca. 15–25 mm long, with spikelets in groups of 3–10 at the ends of short, erect
branches; spikelets 3–6 mm long; achenes smooth, short-cylindric, apiculate-pointed, truncate
basally, 2.5–3.5 mm long. Seepage-fed peat bogs, wet areas; Anderson (McRoberts & McRoberts
3990—BRIT), Smith (Bridges & Orzell 1989a), and Henderson (Turner et al. 2003) cos. in the nc
part of East TX; very rare in the state; mainly se Canada and ne U.S., disjunct s to FL and TX.
Jul–Sep. [Mariscus mariscoides (Muhl.) Kuntze] First reported for TX in 1989 (Bridges & Orzell
1989a) from bogs associated with Queen City Sand (Eocene) and an adjacent terrace. While not
officially designated as such (e.g., TOES 1993; Carr 2002d; Poole et al. 2002), given its limited
distribution in the state, we consider this species to be of conservation concern in TX. It is possibly
a glacial age relict—surviving in a specialized microhabitat, long after the general climate
of the area is no longer appropriate (Kral 1966; MacRoberts & MacRoberts 1997; Diggs 2002;
Diggs & O’Kennon 2003). �
CYPERUS L. FLAT SEDGE, UMBRELLA SEDGE, SEDGE-GRASS
Annuals or usually perennials; plants largely glabrous except for scabrous-margined leaves;
culms (= stems) triangular in cross section; leaves basal or nearly so; inflorescences terminal,
head-like or umbel-like, often conspicuously branched, leafy-bracted at base; scales of spikelets
usually 4–many, usually visibly 2-ranked (= in two distinct rows), the spikelets � flattened or
square in cross section, usually with 3–many bisexual flowers; perianth bristles absent; style
branches 2 or 3; achenes � 1 per spikelet, trigonous or lenticular, without a tubercle.
AA genus of ca. 600 species of annual or perennial herbs of pantemperate and tropical distribution
(Tucker et al. 2002); as such it is the second largest genus in the Cyperaceae following
Carex (Tucker 1987). The spikelet scales in two vertical rows or ranks (not spirally arranged)
makes Cyperus species easily recognized. Recent phylogenetic analyses suggest that the genus
is paraphyletic with a number of genera embedded within it, including Kyllinga and Lipocarpha
(Muasya et al. 2000a, 2000b, 2002). Cyperus is a taxonomically difficult genus with a number
of taxa apparently hybridizing and intergrading morphologically. Intermediates between C.
croceus, C. echinatus, C. retroflexus, and C. retrorsus are frequently seen. Similar problems occur
within other species complexes. Both C3 and C4 photosynthesis are known in the genus
(Tucker 1987; Li et al. 1999). Some species are problematic weeds while others are cultivated as
ornamentals. The pith from the culms of the commonly cultivated Old World Cyperus papyrus
L. (PAPYRUS, PAPER-REED) was used by the Egyptians to make paper at least 5,500 years ago
and later by the Greeks and Romans (Tucker et al. 2002); the Greek word for the plant was
papyros from which our word paper is derived (Hepper 1992). This species was also used to
make sandals, ropes, and boats (e.g., Moses in the bulrushes). The Greek word byblos was the
name for the white pith of PAPYRUS used in making paper (the pith was cut into strips, glued
together, and then pressed and dried—Zohary 1982); the word byblos became modified into
biblion and was applied to all scrolls or books and eventually to the Bible (Hepper 1992). (Greek,
kupeiros or cypeiros, ancient name for the Eurasian species, Cyperus longus L.—Tucker et al. 2002)
REFERENCES: Kükenthal 1935–1936; McGivney 1938, 1941a, 1941b; Corcoran 1941; Marcks 1972,