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BOTANICAL EXPLORATION IN VENEZUELA - I 127
apex, lighter or even subhyaline toward the base, closely appressed
to the staminate florets, 1.5-2.1 mm. long, 0.4-0.6 mm. wide, obtuse
at the apex, densely villous on the back from about the middle to the
apex and on the margins often to the base, densely bearded at the
apex, or glabrous except for the bearded apex; staminate florets:
sepals 3, separate to the base, subhyaline or stramineous, narrowly
elliptic-oblanceolate, sometimes brownish toward the apex, 0.7-1.5
mm. long, 0.2-0.4 mm. wide, acute at the apex, densely bearded at
and near the apex; petals 3, reduced to tiny suborbicular scales about
0.2 mm. long or less, hyaline, separate to the base, opposite the
filaments and barely reaching the base of the anthers, appressed;
stamens 3, tiny erect, included; filaments about 0.3 mm. long, glabrous;
anthers oblong, white, about 0.3 mm. long, dorsifixed, composed
of 2 parallel more or less versatile thecae, each opening by
longitudinal slits; among the staminate florets are similar ones with
more or less effete anthers, but otherwise identical; pistillate
florets not seen.
Type in herb. New York Botanical Garden, collected on ascent of
ledge along southwest-facing side of Mount Roraima, from beginning
of sandstone bluffs to summit, state of Bolivar, alt. 2255-2620 m.,
September 27, 1944, Julian A. Steyermark 58777. In the absence of
pistillate florets the generic position of this curious species is
uncertain. It is placed tentatively in Rondonanthus because of its
separate petals in the staminate florets and its apparently dioecious
habit. It differs pronouncedly from the only other known species of
the genus, R. roraimae (Oliv.) Herzog, which has the petals of the
staminate florets as long as the sepals and very different involucres.
It
may possibly represent an undescribed genus.
Syngonanthus duidae Moldenke, sp. nov.
Herba acaulescens; foliis rosulatis recurvis usque ad 1 cm. longis
non fenestratis glabratis, ca. 0.5 mm. latis, obtusis; vaginis arete
adpressis ca. 1.5 cm. longis glabris, apice ciliato; pedunculis
solitariis gracillimis 8-15 cm. longis 3-costatis tortis basin versus
breviter pilosis, apicem versus glabris.
Acaulescent herb, or with extremely abbreviated stems; leaves
basal, rosulate, recurved, firm-textured, dull-green, tinted with brickred
or brown, 1 cm. long or less, not fenes trace, the venation indiscernible,
essentially glabrous, 0.5 mm. wide or less, blunt at the
apex; sheaths surpassing the leaves, closely appressed to the
peduncles, about 1.5 cm. long, essentially glabrous except for the
ciliate apex, obliquely split at the apex; peduncles solitary, very
slender, 8-15 cm. long, lightly 3-costate, twisted, short-pilose on the
lower half, glabrous above; heads hemispheric, 3*5-6 mm. in diameter,
white; involucral bracelets lanceolate, about 3-2 mm. long, about 0.6
mm. wide at the base, regularly attenuate to the sharply subacuminate
apex, stramineous or white, glabrous throughout; receptacle densely
white-pilose with rather long hairs; receptacular bractlets oblong or