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A New Juncus Sect. Ozophyllum (Juncaceae) from Peninsular
Florida, U.S.A.
Edwin L. Bridges
Botanical and Ecological Consultant, 7752 Holly Tree Place, NW, Bremerton, Washington
98312, U.S.A. ebridges1@gmail.com
Steve L. Orzell
Avon Park Air Force Range, 29 South Blvd., Avon Park Air Force Range, Florida 33825, U.S.A.
steve.orzell@avonpark.macdill.af.mil
ABSTRACT . Juncus paludosus E. L. Bridges & Orzell
is described and illustrated as a new species from
peninsular Florida, U.S.A., occurring primarily in
hardwood and cypress swamps and adjacent ditches
and marshes. Although closest in diagnostic charac-
ters to J. megacephalus M. A. Curtis, it has been
confused with J. polycephalus Michaux of section
Iridifolii Snogerup & Kirschner based on its overall
size, gross morphology, and floral characteristics.
Differences between J. paludosus and other closely
related species of section Ozophyllum Dumortier are
discussed, and a key is provided to the group within
section Ozophyllum that includes J. paludosus.
Key words: Florida, Juncaceae, Juncus, Ozophyl-
lum.
The genus Juncus L. is of almost worldwide
distribution and contains about 300 species, with 95
species occurring in North America (Brooks &
Clemants, 2000; Kirschner, 2002). Within Florida,
the genus is represented by 21 species (Wunderlin &
Hansen, 2003), 13 of which are found in central
Florida (Wunderlin, 1982). Most of the Juncus species
of the southeastern U.S.A. are clearly differentiated
and not particularly difficult to identify in contrast
with the more complex Juncus taxonomy of northern
climates. Therefore, it was a surprise to the senior
author to uncover—in the course of his work on the
Flora of Florida (Wunderlin et al., 1996; Wunderlin
& Hansen, 2008)—a large number of Juncus
specimens from peninsular Florida. The specimens,
which were mostly labeled as J. polycephalus
Michaux, could not be accommodated within the
species concepts of any known Florida species. At
first, the author suspected a hybrid origin, perhaps
between J. polycephalus and J. megacephalus M. A.
Curtis. Both of these have been reported as growing
intermixed in Florida (Godfrey & Wooten, 1979), and
the uncovered specimens at first appeared to have
some characters of each taxon. However, subsequent
collecting at numerous sites, coupled with detailed
study of the variations present within populations,
revealed unique characters not present in either of the
above species.
Juncus paludosus E. L. Bridges & Orzell, sp. nov.
TYPE: U.S.A. Florida: Highlands Co., moist,
sandy stream banks & adjacent overflow ditch on
S side of Morgan Hole Creek bridge at
Kissimmee Rd., Avon Park Air Force Range,
15 May 2003, S. L. Orzell 26085 (holotype, USF;
isotypes, BRIT, FLAS, FSU, GA, MO, NCU, NY,
TEX, US). Figure 1.
Junco megacephalo M. A. Curtis affinis, sed differt culmis
4–8 mm diam. plus quam 80–150 cm altis, foliis amplissimis
3–7(–8) mm diam., (24–)40–80(–108) cm longis, cataphyllis
et vaginis foliorum caulinorum tepalisque pigmento roseo-
purpureo carentibus, et inflorescentia ex capitulis plus quam
25 composita.
Robust perennial, from short, hard, knotty rhi-
zomes, forming small clumps; culms erect, stiff, terete,
80–150 cm, 4–8 mm diam. near the base, smooth.
Cataphylls 1 to 3, straw-colored to dark brown, apex
rounded; basal leaves 1 or 2 per culm, cauline leaves
2 to 4 per culm; basal leaf sheaths reddish purple at
base, noticeably expanded, with a central spherical
septate zone and broad membranaceous margins, all
other leaf sheaths and blades green; leaf blades terete,
septae drying prominently nodose-septate; leaf sheath
with a prominent membranaceous, short, auriculate
ligule, 1–3 mm; largest leaves (24–)40–80(–108) cm,
3–7(–8) mm diam., straight, not arcuate. Inflorescence
an erect to slightly spreading, terminal, many-branched
cyme, from (10–)15–25 cm, primary branches usually
ascending at angles of 25u–50u, with (15 to)25 to 55(to
80) heads per inflorescence. Heads 20- to 60-flowered,
spherical, 8–12 mm diam., at maturity reddish brown
or brown. Tepals 6, 3.0–4.0 mm, lanceolate-subulate,
tapering to a stiff acuminate reddish brown tip,
NOVON 18: 294–297. PUBLISHED ON 2SEPTEMBER 2008. doi: 10.3417/2006124
subequal, at anthesis with a green zone on each side of
the pale midrib and a hyaline margin, becoming straw-
colored to yellowish brown at maturity. Capsule
lanceolate to subulate, light yellowish brown, 4–
5 mm, tapering gradually to the long subulate beak,
the beak exserted from the tepals at maturity, the valves
remaining attached at the beak after dehiscence,
capsule 1-locular, fertile throughout or only near the
base; seeds ellipsoid to ovoid, 0.3–0.5 mm, finely
reticulate, with prominent longitudinal ridges and
much finer cross-striations, the seed body clear
yellowish brown, abruptly tapered at each end to short
dark brown tips, not tailed.
Distribution and habitat. Juncus paludosus occurs
nearly throughout peninsular Florida south to Monroe
and Broward counties, north to Nassau County, and
west near the coast to Franklin County in the eastern
Florida Panhandle. It is common in forested wetlands
(hardwood swamps, cypress swamps, and hydric
hardwood-palm hammocks) and occasionally in road-
side ditches and freshwater marshes adjacent to these
habitats. While J. paludosus seems to favor seasonally
flowing water and cypress-dominated strand swamps
or sloughs, it is noticeably absent from still-water,
cypress dome depressions. The lack of collections
from the Florida Everglades region is likely explained
by the absence of acidic forested wetlands, in contrast
to the Big Cypress region of southwestern Florida,
where such habitats are prevalent and J. paludosus
has been collected. Juncus paludosus is apparently
endemic to Florida. The authors have not seen or
collected any specimens from outside of Florida,
although it is expected in adjacent southeast Georgia.
IUCN Red List category. Our preliminary conser-
vation assessment is based on the abundance,
distribution, and habitat preference of Juncus palu-
dosus. We recommend that J. paludosus be classified
as a taxon of Least Concern (LC) as set forth in the
IUCN Red List Categories and Criteria (IUCN, 2001).
Juncus paludosus is widespread and is currently
known from 29 Florida counties. It is often locally
abundant and displays considerable habitat breadth,
occurring in both natural and human-altered (roadside
ditches, drainageways, etc.) wetlands.
Phenology. In south and south-central Florida,
Juncus paludosus typically reaches anthesis from
April to May between the winter dry season and the
onset of the summer wet season. Mature capsules can
be found from May to July, but fruiting is somewhat
sensitive to changes in El Nin
˜
o-Southern Oscillation
(ENSO) since ENSO influences winter and spring
rainfall in peninsular Florida (Beckage et al., 2003).
During the La Nin
˜
a phase of ENSO, the dry conditions
make it more difficult to locate fruiting plants, and
capsules may abort or fail to reach maturity.
Relationships. Juncus paludosus, a species of
section Ozophyllum Dumortier, has flowers borne in
heads and leaves that are terete and completely
septate. It is therefore notable that many south Florida
specimens (Austin et al., 1990; Huffman & Judd,
1998; Muss et al., 2003) have been previously
identified as J. polycephalus. Juncus polycephalus is
a member of section Iridifolii Snogerup & Kirschner, a
group characterized by flattened leaves with incom-
plete septae. In general inflorescence morphology, J.
paludosus does resemble J. polycephalus, and many
floral and fruit characters are similar between the two
species. However, J. polycephalus has laterally
Figure 1. Juncus paludosus E. L. Bridges & Orzell. —A.
Base of plant. —B. Inflorescence. —C. Perianth and
capsule. —D. Seed.
Volume 18, Number 3 Bridges & Orzell 295
2008 Juncus paludosus (Juncaceae)
flattened, slightly arcuate, incompletely septate leaf
blades and lacks a membranaceous ligule at the apex
of the leaf sheath. In contrast, J. paludosus has terete,
stiff and straight, strongly completely septate leaf
blades and a prominent 1–3 mm long membranaceous
auriculate ligule. In fact, the leaf blades of J.
paludosus are among the most strongly nodose-septate
in the genus, with the septae evident on dried leaves
as hardened, ring-like bands. In central Florida and
northward, both species are known to occur, although
there are very few specimens of J. polycephalus south
of Gainesville, Florida. This is reflected in the
distribution map in Brooks and Clemants (2000), with
the dot in peninsular Florida representing a Polk
County record.
Within section Ozophyllum, Juncus paludosus falls
within a small group having many-flowered spherical
heads, capsules exserted beyond the perianth, and
seeds without membranaceous tails. This group
consists of J. validus Coville, J. nodatus Coville, J.
scirpoides Lamarck, and J. megacephalus. Juncus
validus has leaves that are often laterally com-
pressed (as in J. polycephalus) but with complete
septae. It further differs from J. paludosus in its
widely spreading, relatively few-headed inflores-
cence, lack of basal cataphylls, and capsules with
valves usually separating at dehiscence. Juncus
nodatus, a much smaller plant of northern and
western North America, does not occur in Florida.
Juncus scirpoides is a smaller plant than J.
paludosus, with shorter leaves and a more compact
inflorescence of fewer heads, which are usually
lobed rather than spherical.
The remaining species in this group, Juncus
megacephalus, is perhaps the closest to J. paludosus
in overall morphology, but with many important
differences. It is typically a smaller-statured plant,
rarely to 1 m tall, with culms 3–4 mm wide, leaf
blades less than 25 cm long, and rather compact
inflorescences, usually with fewer than 20 heads.
Juncus megacephalus is suffused with more reddish
purple pigment than J. paludosus, particularly in the
cataphylls, leaf sheaths, and tepals. Live material of J.
megacephalus is easily recognized by its deep wine-
red lower leaf sheaths and cataphylls, the bluish cast
of the culms and leaf blades, and dark reddish black
flowering heads. In contrast, the prominent hues in J.
paludosus are yellowish green and stramineous to light
brown, with little reddish purple pigment.
Paratypes. U.S.A. Florida: Brevard Co., 27 Jan. 1992,
Grey s.n. (USF), open roadside, US 192, 12 mi. W of
Melbourne, Baltzell 8053 (FLAS); Broward Co., Hwy. 441 W
of Deerfield Beach, Atwater #GS-42 (FLAS); Charlotte Co.,
dry cypress swamp, 7 May 1947, Frye s.n. (FLAS); Citrus Co.,
Withlacoochee River, Hartman 72A (FLAS), Woodward Park
Inlet, Kings Bay, Crystal River, Hartman 42 (FLAS); Collier
Co., trailside swamp, Big Cypress, W of FL 29, Lakela &
Almeda 29960 (USF), Scenic Dr., vic. Fakahatchee, Lakela &
Almeda 30007, 30740 (USF), Everglades, along Rte. 94, 21
Apr. 1936, McDaniel s.n. (FSU), cypress swamp, bridge 121,
6 Apr. 1942, Davis s.n. (FLAS), ditch beside Janes Hwy.,
Fakahatchee Strand, Avery & Churchill 2058 (FLAS), swamp
forest E of Janes Mem. Scenic Dr., Fakahatchee Strand St.
Pres., Bridges 23510 (BRIT, FLAS, FSU, GA, NCU, NY,
USF), 23511 (FLAS, USF); Dixie Co., 15 mi. NW of Cross
City, Kral & Redfearn 2677 (FSU); Duval Co., Jacksonville,
Curtiss 2981 (FLAS); Franklin Co., Apalachicola River, NW
of Apalachicola, Kral & Redfearn 2741 (FSU); Gilchrist Co.,
4 mi. E of Trenton, 5 Oct. 1940, West & Arnold s.n. (FLAS);
Hendry Co., Big Cypress Indian Reservation, 8 May 1961,
Jennings s.n. (FLAS); Highlands Co., natural drainage E side
of Morgan Hole Rd., Avon Park Air Force Range (hereafter
APAFR), Orzell 25278 (BRIT, FLAS, FSU, GA, NCU, NY,
USF), Orzell 25280 (BRIT, FLAS, FSU, GA, NCU, NY, USF),
N side of Morgan Hole Creek bridge, APAFR, Orzell 25281
(BRIT, FLAS, FSU, GA, NCU, NY, USF); Hillsborough Co.,
N of Tampa, Crewz 1590, 1600 (USF), along Morris Bridge
Rd., Burch 6827 (USF), Morris bridge wellfield, 29 May
1985, Lopez s.n. (USF), bank of Cypress Creek, Lakela 26057
(USF); Jefferson Co., ca. 4 mi. E of Newport, Godfrey 75147
(FSU); Lee Co., swamp edges W of headwaters of Halfway
Creek, ca. 1 air mi. NE of Coconut on Estero Bay, Orzell &
Bridges 19385 (FLAS, USF); Levy Co., both sides of FL 24 at
E end of Waccasassa River bridge, Cochrane 8883 (USF), N
side of rd., Otter Creek, Gunter & Horsburgh 45 (FLAS),
6 mi. W of Otter Creek, Dunevitz 38 (FLAS); Manatee Co.,
along FL 70, 6 mi. E of the Braden River, 12 Mar. 1969,
Burgis s.n. (FLAS); Monroe Co., FL Rte. 94, SE of Monroe
Station, Godfrey, Ward & Burch 63552 (FLAS, FSU); Nassau
Co., vic. of O’Neil, Godfrey 64113 (FSU); Orange Co., ca.
2.5 mi. N of FL 50 at Christmas, Orlando Wild. Park, Orzell
& Bridges 21681 (FLAS, FSU, USF), Tosohatchee St.
Reserve, Bridges 24520 (BRIT, FLAS, FSU, GA, NCU,
NY, US, USF); Osceola Co., along US 192, 13.4 mi. SE of
Holopaw, Baltzell 8055 (FLAS), Crabgrass Creek, Bull Creek
WMA, Hall 567 (FLAS); Pasco Co., pond S of SR 54, Genelle
& Fleming 99 (USF), 9 June 1961, Riegler s.n. (USF);
Pinellas Co., Brooker Creek Preserve, Hansen, Wunderlin &
Douris 12081 (USF); Polk Co., Hard Luck Hammock,
APAFR, Lindsey & Upchurch 778 (USF), N of Tick Island,
APAFR, Orzell 23713 (USF), Tick Island Slough, APAFR,
Orzell 25285 (FLAS, FSU, USF), SE of sewage disposal plant,
APAFR, Orzell 25287 (BRIT, FLAS, FSU, GA, NCU, NY,
US, USF), 12 mi. NNW of Lakeland, Kral 7282 (FLAS, FSU,
USF); Putnam Co., Sweetwater Creek, Martin & Cooper 624
(FLAS, FSU); Seminole Co., near Little Wekiva River, 2 mi.
W of Altamonte Springs, Baltzell 3924 (FLAS), Wekiva River
at FL 46, Myint 941 (FLAS); Sumter Co., 0.5 mi. W of
Tarrytown, Kral 6860 (FLAS, FSU, USF); Taylor Co., 4 mi. S
of Salem, Kral & Redfearn 2683 (FSU); Volusia Co., E side of
Rte. 3, 24 May 1975, Poppleton & Shuey s.n. (USF), Maytown
Rd., 1.9 mi. W of Cow Creek, Robinson & Hansen 189 (USF);
Wakulla Co., ca. 5.5 mi. WSW of Newport US 98 at bridge
across Wakulla River, Hansen & Richardson 5865 (USF),
along US Hwy. 98, 1 mi. E of Newport, Wiggins 20034
(FLAS).
The following key (modified from Brooks &
Clemants, 2000) distinguishes Juncus paludosus from
other members of section Ozophyllum (subgenus
Septati Buchenau, as used in Brooks & Clemants,
296 Novon
2000) with three stamens, flowers borne in more or
less spherical heads of usually more than 15 flowers,
and without tailed seeds. This key should be inserted
at couplet 16 in Brooks and Clemants (2000: 241). Of
the species included in this key, only J. acuminatus
Michaux, J. scirpoides, J. megacephalus, and J. validus
var. validus are found within any part of the known
range of J. paludosus.
SUPPLEMENTAL KEY TO PART OF JUNCUS SECTION OZOPHYLLUM (SUBGENUS SEPTATI, SENSU BROOKS &CLEMANTS, 2000) IN NORTH AMERICA
1a. Plants strictly caespitose, without any short, hard, knotty rhizomes; tepals lanceolate . . . ....J. acuminatus Michaux
1b. Plants with at least some short, hard, knotty rhizomes, but sometimes appearing nearly caespitose due to very short
rhizome internodes; tepals lanceolate-subulate.................................................2
2a. Capsules shorter than the tepals, and clearly included within the tepals at maturity . . J. brachycarpus Engelmann
2b. Capsules equaling or exceeding the tepals, exserted from or only slightly included within the tepals at maturity . . . 3
3a. Capsule valves remaining united at the apex after dehiscence . . .............................4
4a. Leaves laterally compressed; heads 6- to 15-flowered ....... J. validus var. fascinatus M. C. Johnston
4b. Leaves strictly terete; heads 20- to 60-flowered ......................................5
5a. Culms 4–8 mm in diam. near the base, usually more than 80 cm tall; inflorescence usually more
than 15 cm tall, with more than 25 heads; largest leaf blades more than 25 cm long and 3 mm in
diam .........................................J. paludosus E. L. Bridges & Orzell
5b. Culms 1–3 mm in diam. near the base, usually less than 80 cm tall; inflorescence usually less
than 10 cm tall, with less than 25 heads; largest leaf blades less than 25 cm long and 1–2 mm in
diam ................................................................6
6a. Heads usually at least somewhat lobed; tepals green to straw-colored, nearly equal in length;
basal leaf sheaths and cataphylls straw-colored to brown ........... J. scirpoides Lamarck
6b. Heads strictly spherical; tepals 6 reddish brown to purplish, the inner tepals somewhat
shorter than the outer; basal leaf sheaths and cataphylls deep reddish purple........
.............................................J. megacephalus M. A. Curtis
3b. Capsule valves separating at the apex during dehiscence ...................................7
7a. Tepals 4–5 mm long; leaves laterally compressed ..................J. validus Coville var. validus
7b. Tepals 2.9–4.0 mm long; leaves terete ............................................8
8a. Capsules 3.5–5.0 mm long, exserted; culms 0.4–3 dm tall....................J. nodosus L.
8b. Capsules 3.0–3.5 mm long, equaling perianth or slightly included; culms 2.5–8.5 dm tall ....
....................................................J. bolanderi Engelmann
Acknowledgments. We thank Paul Ebersbach, Chief
of the Environmental Flight at Avon Park Air Force
Range (APAFR), for his continued support of scientific
research; Rebecca Yahr for production of the illustration;
Scott Penfield, retired from APAFR, for providing
funding for the illustration; and Douglas Ripley, retired
from the U.S. Air Force in Washington, D.C., who
secured funding for the manuscript. Fieldwork was
facilitated by numerous land managers at several state
and federal conservation lands. We thank Guy Nesom of
BRIT for providing the Latin diagnoses. We thank
herbarium curators, especially Richard Wunderlin and
Bruce Hansen at USF and Kent Perkins at FLAS. We
particularly thank Jan Kirschner for providing details on
the current subgeneric classification of Juncus.
Literature Cited
Austin, D. F., J. L. Jones & B. C. Bennett. 1990. Vascular plants
of Fakahatchee Strand State Preserve. Florida Sci. 53: 89–117.
Beckage, B., W. J. Platt & M. G. Slocum. 2003. Influence of
the El Nin
˜
o Southern Oscillations on fire regimes in the
Florida Everglades. Ecology 84: 3124–3130.
Brooks, R. E. & S. E. Clemants. 2000. Juncus. Pp. 211–255 in
Flora of North America Editorial Committee (editors). Flora
of North America North of Mexico, Vol. 22. Oxford
University Press, New York.
Godfrey, R. K. & J. W. Wooten. 1979. Aquatic and Wetland
Plants of Southeastern United States: Monocotyledons.
University of Georgia Press, Athens.
Huffman, J. M. & W. S. Judd. 1998. Vascular flora of
Myakka River State Park, Sarasota and Manatee counties,
Florida. Castanea 63: 25–50.
IUCN. 2001. IUCN Red List Categories and Criteria Version
3.1. Prepared by the IUCN Species Survival Commission.
IUCN, Gland, Switzerland, and Cambridge, United
Kingdom.
Kirschner, J. (editor). 2002. Species Plantarum: Flora of the
World, Pt. 7, Juncaceae 2: Juncus subg. Juncus. Australian
Biological Resources Study, Canberra.
Muss, J. D., D. F. Austin & J. R. Snyder. 2003. Plants of Big
Cypress National Preserve, Florida. J. Torrey Bot. Soc.
130: 119–142.
Wunderlin, R. P. 1982. Guide to the Vascular Plants of
Central Florida. University Press of Florida, Tampa.
——— & B. F. Hansen. 2003. Guide to the Vascular Plants
of Florida, 2nd ed. University Press of Florida, Gaines-
ville.
——— & ———. 2008. Atlas of Florida Vascular Plants.
,http://www.plantatlas.usf.edu/., accessed March 2006
[Landry, S. M. & K. N. Campbell (application develop-
ment), Florida Center for Community Design and Re-
search]. Institute for Systematic Botany, University of
South Florida, Tampa.
———, ——— & E. L. Bridges. 1996. Atlas of the Flora
of Florida. Florida Department of State, Tampa
[CD-ROM].
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