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BOTANICAL EXPLORATION IN VENEZUELA - I 43
original publication by Clarke 6 who
,
based his description on Spruce
3614 from "Maypures; in Upper Orinoco", a locality on the Colombian
side just south of the present collection, which is the first record for
Venezuela.
Clarke's original description of the achene as "levi, papillosa,
fusca" is both inadequate and misleading, especially as regards the
use of the word "levi". The rows of tooth-like projections or
papillae on one face certainly belie this part of Clark's description.
As far as the achene is concerned, this species is one of the most
distinct in the entire genus. There is no doubt, however, what
Clarke had in mind about the peculiar markings, since, near the end
of his description, he states that the achene is "praesertim in parte
superiore a papillis erecta ornata. Ceteroquin fere ut R. Trichochaeta".
Both R. Trichochaeta and the Mexican R. mexicana have
markings on the achene similar to those found in R. den tin ux.
The following is a description of the achene based on the present
collection: body blackish, 3 mm. long, both surfaces minutely
granulose-puncticulate, but marked on the inner surface with 2 rows
of 10-12 ridges and depressions, the ridges curved, a longitudinal
ridge running down the center between these ridges; beak prominent,
tawny, bidentate, 2 mm. long, 0.5 mm. wide, antrorsely setulose;
awns 5-6, buff-tawny, antrorsely scabrous, surrounded at base by 5
buff-stramineous tufts of hispidulous hairs, 4.5-5 mm. long (Fig. 5, d).
Rhynchospora duidae Steyermark, sp. nov.
Perennis caespitosa; foliis 15-50 cm. longis, 6-7 mm. latis, planis
laevibus, marginibus serratis; culmis erectis trigonis laevibus, 6-7
dm. altis; corymbis pallido-stramineis axillaribus terminalibusque
contractis, 2-2.5 cm. longis, 1-2.5 cm. latis; involucri bracteis 1-2,
2-3 cm. longis, 1.5-2 mm. latis; spiculis lanceolatis (immaturis)
6.5 mm. longis, 3-4-carpis; setis 6 antrorse hispidulis, 4.5-5 mm.
longis (immaturis ?); stylo profunde diviso, ramis longis; tuberculo
lanceolate.
Type in herb. Chi. Nat. Hist. Mus., collected on summit of Cerro
Duida, Savanna Hills, Territorio Federal Amazonas, alt. 1065-1220
m., September 2, 1944, Julian A. Steyermark 58254.
Rhynchospora karuaiana Steyermark, sp. nov.
Perennis; culmis trigonis glabris, foliis excedentibus, 10.5 dm.
altis vel altioribus; foliis paucis glabris, 60-70 cm. longis, 2.5-3.5
ram. latis; fasciculis 4, subcapitatis, remotis longe-pedunculatis
axillaribus terminalibusque, 1-2 cm. longis, 1.5-2 cm. latis; pedunculis
usque ad 7.5 cm. longis; bracteis infimis erectis scabridulis,
10 cm. longis, 1-2 mm. latis; spiculis 3-6 lanceolato-ellipticis,
6
Clarke, C. B. New Gen. & Sp. Cyp., Kew Bull. Add. Ser. VHI:
33. 1908.