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BOTANICAL EXPLORATION IN VENEZUELA - I 41
Rhynchospora culmenicola Steyermark, sp. nov.
Perennis caespitosa; culmis supra foliatis, 25-30 cm. altis, 0.75-
1 mm. latis; foliis erecto-adscendentibus, supra aggregatis, infra
fere glabris vel parce adpresso-pilosulis, supra magis pubescent! bus,
pilis rainutis adpressis, marginibus incurvatis, costa manifesta carinata;
vaginis puberulis vel glabrescentibus; paniculis 4-8, laxe
racemosis, 0.5-1.5 cm. longis, axillaribus terminalibusque; pedunculis
filiformibus flexuosis, 3-5-5 cm. longis, 1.5-4.5 cm. longis; spiculis
1-3 fusiformi-ellipticis, 5.5-6 mm. longis, 1-1.2 mm. latis, 2-floris,
2-carpis, subsessilibus, pedicellis glabris, 0.5-1.5 mm. longis;
squamis ovatis vel ovato-lanceolatis breve aristatis castaneis; setis
nullis vel 2-3 rudimentariis; achaenio subrhomboideo-oblongo,
1 mm.
longo, subtilissime areolato, transversim striolulato stramineo; tuberculo
triangular i-lanceolato, fructu longiore 1.6 mm. longo; stylo
ramis brevibus.
Leaves more prominently pubescent with minute appressed hairs on
upper surface, these lying on surface enclosed by incurved margins,
midrib prominent and keeled on one side, 12-15 cm. long, 1-1.5 mm.
wide; panicles loosely racemosely scattered in the upper half of the
culm; uppermost bract exceeding inflorescence; spikelets with 5-6
scales; scales 1-6 mm. long; bristles none, or 2-3 short processes
at very base of achene with or without serrulations; achene biconvex,
stramineous, abruptly narrowed below, rounded or subtruncate above,
finely and shallowly areolate with transverse reticulations, the cells
broader than high (Fig. 6, b).
Type in herb. Chi. Nat. Hist. Mus., collected around summit of
Cerro Negro, above La Sabana de las Piedras, northwest of Caripe,
state of Monagas, alt. 2180 m., April 15 f 1945, Julian A. Steyermark
62110. Also collected in shady, moist, bamboo thickets, Cerro
Tururaiquire, between headwaters of Rio Colorado and summit of
southern peak, state of Sucre, alt. 2200-2400 m., May 7, 1945,
Steyermark 62635.
This species belongs to Series Haplostyleae, Div. Calyptrostylis,
Sect. Racemosae (following Clark's divisions). It is related to /?.
cryptantha C. B. Clarke, R. Edwalliana Boeckl., R. racemosa C.,
Wright, R. elongata Boeckl., R. Lechleri Steud., R. uniflora Boeckl.,
and R. Gollmeri Boeckl. From all of these it differs in its combination
of the following characters: ferruginous or castaneous spikelets,
relatively smooth achenes, long beak, no setae or with 2-3 rudiments,
foliose culms 30 cm. or less tall, several sparsely simple racemose
inflorescences, glabrous pedicels, elongate flexuous peduncles,
leaves 1-1.5 mm. wide, and appressed-pilosulous blades and sheaths.
Rhynchospora dentinux C. B. Clarke
Open savanna and igneous rock outcrops, Puerto Ayacucho, Territorio
Federal Amazonas, alt. 200 m., Steyermark 58512, This is
apparently the first recorded collection of the species since its