James L. Luteyn and Paola Pedraza-Peñalosa
The New York Botanical Garden
TEPUIA
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Tepuia Camp (Ericaceae: Vaccinioideae:
Andromedieae) is a genus of terrestrial, woody rhizomatous, thin-stemmed
shrubs to subshrubs endemic to the open, low-shrub savannas on the tepuis
of the Guayana Highlands of southeastern Venezuela. It is characterized
by leaf margins with 1-4 pairs of round, sessile to short-stipitate, pustular
glands at the base and sometimes also on the petiole, racemose inflorescences,
connate and apical bracteoles, sympetalous corollas, anthers with tubules,
and baccate fruit. I have noted in the field
that the roots of both T. venusta and T. tatei have a
strong wintergreen odor when crushed which would indicate the presence
of the methyl ester of salicylic acid. Apparently all species of Tepuia reproduce vegetatively by rhizomes. Seven species are
here recognized, and all should be considered rare and threatened.
The genus is a homogeneous group placed within Andromedeae (Vaccinioideae), but having affinities with the Vaccinieae
(see Stevens, 1995). Tepuia was previously reviewed by Steyermark (1967) and Maguire, Steyermark and Luteyn (1978). Luteyn (1995c) again revised the genus from which this treatment is taken. There are very few herbarium collections of the genus and much additional field work is needed for a complete understanding of its variation and relationships. |
Erect, terrestrial, shrublets to shrubs with bark thin, longitudinally cracking; indumentum consisting of simple, glandular and eglandular hairs. Leaves alternate, petiolate; blades entire, flat to revolute, coriaceous, glabrous to densely tomentose, bearing at base along margin and sometimes onto petiole 1-4 pairs of ± circular, sessile (flat) to stipitate, pustular glands; venation pinnate. Inflorescence axillary, racemose (very rarely weakly branched near base); floral bract one, small; bracteoles two, connate basally, located at apex of pedicel and subtending flower, persistent. Flowers perfect, 5-merous with imbricate aestivation; calyx articulate with the pedicel, often short-stipitate, rotate-campanulate, deciduous with fruit, lobes distinct nearly to base; corolla sympetalous, ± urceolate to campanulate-urceolate, bluntly 5-angled (bluntly plicate or somewhat pouched), pink to red, lobes reflexed, glabrous to short-tomentose; stamens 10, included; filaments distinct, flat, base dilated, long-pilose, unappendaged, attached dorsally near base of anther; each anther divided into a basal, weakly papillate theca with short-mucronate bases and two terminal tubules, unappendaged, dehiscing introrsely by oblique (flaring) pores; pollen without viscin threads; ovary superior, depressed-globose, bluntly pentagonal, 5-locular, smooth, glabrous to densely tomentose, placentation axile, nearly basal; ovules numerous, anatropous (fide Camp, 1939); nectariferous disc surrounding base of ovary, 10-lobed with tiny, finger-like projections alternating with filaments; style impressed, cylindric, elongate, inserted; stigma truncate to depressed-capitate, ± lysigenous. Fruit a berry, spherical, basically glabrous, smooth, probably always red; seeds numerous, trigonous to ± trapezoid and flattened, 1.4-1.7 mm long, without wings or tails, orangish-brown, testa reticulate to reticulate-foveolate, the cells ± isodiametric to elongated, thin-walled; embryo white; chromosome number unknown.
Key to Neotropical Species Back to Top
1. Ovary densely ferruginous-tomentose, the surface obscured;
corolla densely
pilose along angles and glabrous between;
rachis, pedicels, bracteoles
densely grayish- to ferruginous-tomentose.
2. Lamina 1.5-3 x 0.7-1 cm, strongly
concave, margins revolute, venation
obscure;
rachis 0.2-0.8 cm long .............................................. T. vareschii.
2. Lamina (1.5-)3-7.5 x (0.8-)1.3-4
cm, basically flat, margins only
narrowly revolute,
venation ± conspicuous; rachis 1-7.5 cm long.
3. Calyx
densely ferruginous-tomentose on all external surfaces;
petioles (5-)7-13 mm long; pustular glands 3-4 pairs .......... T. speciosa.
3. Calyx
glabrous on external surfaces or only pilose along the lobes;
petioles 3-7 mm long; pustular glands 1-2(-3) pairs.
4. Mature stems and twigs bearing gland-tipped, hispid hairs;
calyx usually glabrous on external surfaces ..................... T. cardonae.
4. Stems and twigs without hispid hairs; calyx lobes
ferruginous-pilose along middle portion ........................ T. intermedia.
1. Ovary glabrous or sparsely to moderately pilose, the actual
surface
obvious, not obscured; corolla glabrous
or only sparsely pilose along
angles distally; rachis, pedicels, and
bracteoles moderately grayish-
or whitish-tomentose or pilose, or glabrous.
5. Stems, twigs, and petioles bearing
tiny, pustular glands on surface .....
....................................................................................... T. multiglandulosa.
5. Stems, twigs, and petioles without
tiny, pustular glands on surface.
6. Lamina
0.3-0.7 cm broad, oblong-elliptic, apex rounded, very
strongly concave with margins deeply and broadly revolute
including apex ...................................................................... T. venusta.
6. Lamina
(0.3-)0.6-1(-1.3) cm broad, ovate-elliptic, apex acute
with actual apex conspicuous and bluntly mucronate, lamina
basically flat to revolute, but not apex ......................................... T. tatei.
This is a version of the taxonomic treatment of Tepuia by James L. Luteyn, modified from "Ericaceae--Part II. The Superior-Ovaried Genera (Monotropoideae, Pyroloideae, Rhododendroideae, and Vaccinioideae p.p.)." The full treatment including specimen citations may be seen in Flora Neotropica Monograph 66: 351-364 (Luteyn, 1995c). This on-line synthesis is published with permission of The New York Botanical Garden.