A NEW SPECIES OF CAREX (CYPERACEAE) FROM URUGUAY AND A NEW NAME IN THE GENUS

7 Pages·1996·3.4 MB·English

by  Gerald A Wheeler

NEW
FROM
A OF CAREX (CYPERACEAE)
SPECIES
NEW
URUGUAY AND A NAME THE GENUS
IN
WHEELER
GERALD
A.
Department Plant Biology
oj
Minnesota
University
of
MN
33108-1095,
U.S.A.
Paul,
St.
newly described from the Department of Flo
is
)
from the holotype. This very distinctive, bi
ily
/ing large, glabrous perigynia that are distinctl;
srican plants previously called C. phalaroides
'
IDepartamentodeFlo,
Digitatae) se elevan aqui al range
estimated that ovet 200 species of Cay
It is
Of
South Ametica (Wheeler 1996). those gtov
Uruguay
under 20 have been reported from (Osten
the continent, slightly
Wheeler
1931; Chebataroff 1942; Herter 1953; Pedersen 1969; 1987,
new from Depart-
1988). In this paper, a species oi Carex reported the
is
new name
ment of Florida in southern Uruguay. In addition, a is offered
Kunth
Kuk.,
here for plants previously called C. phalaroides var. crassiflora
which South America.
occur southeastern
in
G. A.Wheeler,
i
:
mts from
loosely cespitose short rhizomes, low-growing. culms
Fertile
cm
with brownish
tall, glabrous, basal sheaths. Leaves
ca. 7, basal,
mm
dmg
cm
the culms; blades 1.5-4 0.8-2
long, wide,
ca. or
flat
lelled proximally, the margins ciliate (but only sparingly so near the
leaf sheaths very short, glabrous; inner band of leaf sheaths hyaline
;
mm
brown,
glabrous; ligules 0.5-1 long, rounded. Inflorescences
le
cm
5 long, the terminal spike slightly larger than the lateral ones.
mm
werm
spikes strongly oveidapping; lo ost bract scale-like, 3.5-5 long,
mm
mm
thac awn wide and up
ca. 2.5 wide, sheathless, wi iliate ca. 0.8 to
cm
androgynous.
2.5 long, the upper ones sonlewht reduced. Spikes ca. 3,
It
.
mm
cm
Termii spikes long; stam inate portion 8 long and 2.5
lal ca. 1 ca.
mm mm
mm
w
7-flowered; Hate portion 6 long and 4.5
ide, ca. pisti ca.
mm
3-flowered Lateral spi kes5--7 long, on smooth peduncles up
:a.
.
m
m
to 4 long; staniinate portK3n inc:onspicuous, ca. 2-3-flowered; pistU-
mm mm
4-6 nd4-5
portion long wide, 3-4-flowered. Pistil-
late ca. ca.
a:
late scales exceeding the perigy nia(a least the prolonged tips), the bodies
y
t
mm mm
green
3.6-5 long, 1.8-2.6 wide, Dvate-lanceolate, glabrous, pale
c
wh brown
mineous with broad, hyaline or pale margins, 3-
or strai cent-er lite
up
veined the midvein prolonged into a cuspidate or sparingly aristate tip
, .
mm
green stramineous
1.3-1.9 wide, ovate-lanceolate, glabrous, pale or
brown
center with broad, white hyaline or pale margins, 3-veined, the
mm
up 4
midvein prolonged into a cuspidate or sparingly aristate tip to
mm mm
somewhat
long. Perigynia 4.4-4.8 long, 2-2.3 wide, erect or
rhombic
spreading, strongly trigonous with slightly concave, elliptical to
and
glabrous, pale green or stramineous, 2 distinct veins the rest
sides,
obscure (however, several short veins are usually visible near the base), not
the margins sharply angled and smooth, tapered to a stipitate-like
inflated,
mm
base 0.6-1.2 long), more or less abruptly contracted into a broad
(ca.
mm
apex
beak; beaks 0.8-1.2 long, whitish green (especially distally), the
weak up
(when and
minutely bidentulate, the teeth present) to
entire or
mm mm
mm
long. Achenes 3-3-3.5 long, 1.8-2 wide, sharply trigonous
0.
1
with slightly concave, rhombic sides, closely enveloped by the perigynium,
brown with yellowish angles, apiculate, sessile or nearly so. Stigmas 3.
unknown.
Anthers
Serendipity undoubtedly plays a role in scientific discovery. For instance,
new
W. G. Herter apparently was not aware that he had discovered a spe-
when commonly-occurring Carex
collecting plants of the phalaroides.
cies
On
the herbarium sheet containing the holotype of C. herten are seven plants
new
and
of C, phalaroides a single plant of the species (Fig. 1).
m
URUGUAY. W.
Type: Dept. Florida: Escancia SanraCruz, campis, Sep 1926, legit.
known The was
Carex herten only from the type locality (Fig. 2), plant
is
collected "in campis" (on a plain) and has fully-developed perigynia and
The new named honor Wilhelm G. Herter
of
ripe achenes. species in
is
who
who made and was an
(1884-1958), the type collection also indefati-
worker on Uruguay.
gable the of
flora
•
C.
gibertii
O
C.
herteri
f^
As
evident
in Fig. the perigynia o( Carex appear be ove
IS 1, herteri to
diminutive
sized for the stature of the plant. Indeed, the combination
i
large perigynia with few of them per spike, large achenes that are strong
and with
apiculate, leaves ciliate margins, readily separates
this specii
from Uruguayan
all other carices. It appears to be most closely related
i
Wheeler, Carex (Cyperaceae) from Uruguay 4/5
members
complex
of the C. phalaroides species (sect. Digitatae (Fries) Christ
subsect. Radicales Kuk., sensu Kiikenthal 1909), a group of mostly South
American carices characterized by having androgynous spikes, cuspidate
scales, and sharply trigonous achenes. Although the aspect of C. herteri and
C. phalaroides strikingly similar, they differ in several features. For ex-
is
ample, the former differs from the latter by having: ciliate leaf margins;
much
and
fewer perigynia per spike; larger perigynia that are glabrous
and
distinctly beaked; larger achenes that are strongly apiculate; differ-
ently-shaped Also Table
scales. see
1.
Notably, numerous sheets oi Carex phalaroides have been examined from
Argentina, southern southeastern Paraguay, and Uruguay,
eastern Brazil,
but thus only the holotype of known. seems remarkable
far C. herteri It
is
that a species with such large and distinctive perigynia as C. herteri has
hitherto been overlooked. However, the diminutive stature of both C, herteri
and phalaroides, and their physiognomic similarity to each other, un-
C.
doubtedly has contributed to the former species having been overlooked in
may The
Another
the past. factor be the early fruiting date of this species.
known
plants are to bear ripe achenes in early October, indicating that the
species probably flowers in late July and August. Also, though as yet unveri-
may
fied, C. herteri be a local endemic with only a few existing populations.
iG. A. Wheeler,
uncommonly known
from
CavLX gihertu an collected species, thus far
is
Growing
southern Hrazih UriigLiay, and northeastern Argentina. in dry
September and October and mature has been
flowers in late fruit
sites,
It
November The
collected from through March. epithet not avail-
crassiflora is
Hence,
able for use at species rank because of the earlier C. crassiflora KiAk.
name Uruguayan
here offer the C. gibertii for the species, after the bota-
1
who made The
nist Jose Ernesto Gibert (1818-1886), the type collection.
Lam. C-D).
plant has been illustrated in Chebataroff (1942,
I,
ARGENTINA.
Pr
dd. Clonal specime ns imined: {Ccv.x gibevW):
ty.i
21H3 BRAZIL. Gran
of Rio
State
(LIL).
ickert
ov 1955, 5rfa-o 404:(F). Uruguay. Depart. San Jose: Mauncio, ba
.^/,m#40/6(SI).
new member
Like the species described earlier, Carex gibertii a of die
is
C. phalarotdes species complex. Kiikenthal (1905, 1909) and subsequent
workers (Osten
1931, Chebataroff 1942) have
called these plants
C.
phalarotdes var. crassiflora, but there appears to be a real discontinuity in
morphology between
the two. Indeed, examination of type material, along
with other specimens, two
reveals that the entities are closely related yet
taxonomically distinct species. Carex gibertii differs from C. phalarotdes by
having and
larger spikes, perigynia, achenes, In Table have
scales. cal-
1, I
mean
culated values of several characters for both species, and, in each case,
the corresponding means two
are so disparate that species are strongly
stig-
gested. For example, perigynium mean length and width
in C. giberttt are
mm
mm
mm,
and
3.8 .7 respectively, whereas those in C. phalarotdes are 3
1
mm.
and Also, no intergrades between these two species have been
1.3
seen. Moreover, the two apparently grow in different habitats. Carex gibertii
has been collected "in saxosis" (rocky soil) and in "barrancas" (ravines),
whereas C. phalaroides frequents moist meadows and grasslands, pastures,
and embankments.
roadside
Carex from by having culms, leaves lacking
gibertii differs C. herteri taller
marginal hairs, more perigynia per spike, smaller achenes and scales, and
A
slightly smaller perigynia that are pubescent and shorter beaked. mor-
phological comparison of 13 characters the three species discussed in
for
paper given Table
this in
is 1.
want thank the curators and directors of the following herbaria for
to
I
BAA,
the loan of specimens of the Carex phalaroides species complex: B,
BAB, BM, GH, MICH, MIN, MO, NY, SGO, UC,
G, K,
C, LIL, P, S, SI,
F,
WIS.
UPS, us, and
guay. Comun. Bot. Mus. Hist. Nat. Montevideo 1-9-
1(3):
Herter, W.G. 1953. Flora del Uruguay V. Glumiflorae III. Revista Sudamer. Bot. 9:129-
KtJKENTHAL, G. 1905. Die von E. Uie gesammeiten brasilianischen Carices. Verb. Bot.
Das
1909. Cyperaceae: Caricoideae. Engler, A., ed. Pflanzenreich, IV.
In:
Wilhelm Engelmann. 1-824.
20, Heft 38. Leipzig: Pp.
OsTEN, C. 1931. Las Ciperaceas del Uruguay. Anaies iVIus. Hist. Nat. Montevideo (set. II)
3:109-256.
Buenos
Pedersen, T.M. 1969. Carex. In: Cabrera, A., ed. Flora de la provincia de Aires.
318-
Buenos Aires: Colec. Cient. Instituto Nacional de Tecnologia Agropecuaria. Pp.
12:97-102.
1996. Three new species oi Carex (Cypera
Hickenia 189-200.
ion for C. ecuadonca. 2(4
1):