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BOTANICAL EXPLORATION IN VENEZUELA - I 171
This species appears to be similar to Pogonia tenuis Reichb. f.,
but differs in having longer floral bracts, larger rose-colored (not
white) flowers and acute (not acuminate) sepals.
It seems to be
allied to P. elegantula Schltr., but has much smaller, narrower
leaves.
Pogonia unifoliata C. Schweinfurth, sp. nov.
Herba terrestris, minor. Caulis gracilis, ima basi dense villosus,
supra glaber, unifoliatus. Folium anguste ellipticura, acutum, sessile,
amplectens, erectum. Flos singulus, bracteatus. Sepala
lanceolato-oblonga, acuta, tubulari-involuta. Petala ellipticooblonga,
paulo breviora, tenuiora. Labellum ezpansum oblongoellipticum,
prope apicem profunde trilobatum; lobi laterales involuti,
cum apice libero brevi rotundato vel obtuso; lobus medius comparate
parvus, in circuitu natural! triangularis, ezpansus suborbiculariobovatus;
discus basi minute bicallosus, fascia mediana late percursus.
Columna brevis, supra sensim dilatata.
Plant terrestrial, rather small. Stem slender, up to about 20 cm.
long, densely brown-villous at the base (doubtless where in contact
with the soil), glabrous above, blue-gray and glaucous, furnished in
the lower third with a minute ovate-lanceolate amplexicaul sheath
and in the upper third with a single leaf. Leaf erect, narrowly
elliptic, acute, sessile, amplexicaul, blue-gray, glaucous, about 2.8
cm. long and 8 mm. wide. Inflorescence 1-flowered, leafy bracted.
Bract similar to the leaf, ovate-elliptic, amplexicaul, acute, deeply
concave and clasping the flower, about 2.5 cm. long, with the tip
little shorter than the floral segments. Ovary slender, plurisulcate,
glabrous. Flower small, apparently a bud. Sepals parallel, fleshy,
pale yellow-green, glaucous, tubular-involute. Dorsal sepal lanceolate-oblong,
acute, 7 -nerved, about 14.5 mm. long and 4 mm. wide
when expanded. Lateral sepals similar, slightly shorter and narrower,
slightly oblique, 5-nerved. Petals elliptic-oblong, acute or subacute,
about 13 mm. long and 4 mm. wide, thinner than the sepals,
pale green, 3-nerved through the middle with lateral nerves branching.
Lip oblong-elliptic in natural poskion, deeply 3-lobed near the
apex, about 12.5 mm. long and 5.8 mm. wide when expanded, pale
greenish white with purple lines; lateral lobes inrolled with short
rounded or obtuse free apex; mid-lobe very small, triangular in
natural position with involute sides, when expanded suborbicularobovate
with crenate margins; disc through the middle with a broad
fleshy band (longitudinally divided above) extending from near the
base about to the middle of the mid-lobe, minutely bicallose at the
base. Column short, gradually dilated upward, white at base with
wine-purple near tip, about 7.1 mm. tall at the back including the
large erect anther (Fig. 27).
Type in herb. Chi. Nat. Hist. Mus., no. 1203948, scrubby forest on
rocky open portion of plateau on southeast-facing slopes, Ptari-tepui,
state of Bolivar, alt. 1600 m., November 1, 1944, Julian A. Steyermark
59630.