10. Ceratostema JUSSIEU Gen. Pl. 163 (1789). -- Type: Ceratostema peruvianum
GMELIN.
- Englerodoxa
HOEROLD, Bot. Jahrb. Syst. 42: 310 (1909). -- Type: Englerodoxa alata
HOEROLD.
- Periclesia
A. C. SMITH, Contr. U.S. Natl. Herb. 28(2): 357 (1932). -- Type: Periclesia flexuosa
- A. C. SMITH.
References: SMITH, A. C., Plants collected in Ecuador by W. H. Camp- Vacciniaceae.
Mem. New York Bot. Gard. 8(1): 41--85 (1952). -- LUTEYN, J. L., New species of Ceratostema
(Ericaceae: Vaccinieae) from the northern Andes. J. Arnold Arb. 67: 485--492 (1986).
Terrestrial or epiphytic shrubs to 3.5 m tall, sometimes scandent, often arising from
lignotubers. Leaves alternate, coriaceous, pinnate or plinerved, petiolate. Inflorescences
axillary, fasciculate, racemose, or flowers solitary; floral bract small to large and showy. Flowers (4-) 5 (-6)-merous, without odor; aestivation valvate;
calyx articulate with the pedicel (obscurely so or continuous in C. loranthiflorum
); hypanthium obconical or campanulate, terete, angled to costate, or winged; limb
suberect or spreading; lobes elongate-triangular or triangular, often distinctly
veined; corolla thick-carnose, often large, subcylindric but often ventricose at
base, terete or more commonly bluntly angled, usually deeply lobed, the lobes usually narrowly-elongate;
stamen (8-) 10, equal or more commonly alternately slightly unequal, nearly as long
as corolla or appearing exserted when corolla lobes become reflexed; filaments distinct or connate, equal or alternately slightly unequal, basifixed, lacking
spurs; anthers equal or alternately slightly unequal, lacking disintegration tissue;
thecae often alternately slightly unequal, usually strongly granular (papillose);
tubules often alternately slightly unequal, much thinner and often 2--5 times longer,
rarely equal to or shorter, than the thecae, flexible, distinct to base to connate
nearly to apex, dehiscing by short, oblique clefts or nearly terminal pores, these
sometimes flaring; pollen lacking viscin threads; ovary inferior; style filiform, as
long as corolla or slightly exserted; stigma truncate. Fruit a spherical, many-seeded,
dark blue-black berry.
The genus Ceratostema
contains ca 32 species ranging from Venezuela to N Peru. Twenty-six species are
endemic to eastern (Oriente) Ecuador, 1 is endemic to the Guayana Highland of Venezuela,
and 3 to northern Peru. Two species are common to southern Colombia and eastern
(Oriente) Ecuador. [NOTE: Unless otherwise stated, measurements in this genus are given
for dried material at anthesis, because considerable elongation of pedicels and calyces
may occur post-anthesis, whereas considerable shrinkage occurs in the corollas upon drying.]
Key to Species of Ceratostema
- 1a.
- Leaves basally attenuate, acute, or rounded, rarely subcordate but not amplexicaul.
- 2a.
- Calyx limb very conspicuous, the lobes at least 10 mm long.
- 3a.
- Calyx hypanthium terete, neither costate nor winged.
- 4a.
- Flowers 4-merous; leaf blade 3.5--6 x 1.2--1.8 cm; flowers in 3--4-flowered
racemes; corolla lobes 20--21 mm long; staminal filaments connate
- .....................................................................C. flexuosum
- 4b.
- Flowers 5-merous; leaf blade 9--13 x 3--5 cm; flowers in fascicles of 4--6;
corolla lobes 4--9 mm long; staminal filaments distinct
- .....................................................................C. fasciculatum
- 3b.
- Calyx hypanthium 10-costate or 5-winged.
- 5a.
- Calyx hypanthium 10-costate.
- 6a.
- Bracteoles located at apex of the pedicel, 13--20 mm long, clasping and concealing
the calyx hypanthium at anthesis; rachis < 1 cm long; plants short-pilose all over
- ............................................................C. bracteolatum
- 6b.
- Bracteoles located at or below middle of pedicel, ca. 4 mm long, not clasping
calyx; rachis 6--8 cm long; plants with glabrous or puberulent habit
- ............................................................C. calycinum
- 5b.
- Calyx hypanthium clearly 5-winged.
- 7a.
- Leaves plinerved, (2-) 3.5--9.5 cm broad; rachis (2-) 5.5--13 (-22) cm long;
floral bract 8--20 mm long; bracteoles apical; calyx (25-) 35--45 mm long, the
lobes (10-) 15--21 mm long; staminal filaments connate
- ............................................................C. reginaldii
- 7b.
- Leaves pinnately-nerved, (0.6-) 1--2.5 (-3) cm broad; rachis (0.3-) 0.6--4 cm
long; floral bract 2--7 mm long; bracteoles basal; calyx 10--35 mm long, the lobes
7--25 mm long; staminal filaments distinct.
- 8a.
- Calyx 28--35 mm long at anthesis, the lobes 19--25 mm long; rachis 1--1.5 (-4)
cm long
- ...................................................C. megalobum
- 8b.
- Calyx 10--22 mm long at anthesis, the lobes 7--15 mm long; rachis 0.3--1.1 cm
long.
- 9a.
- Leaves beneath and flowers (pedicel, calyx, corolla) short-pilose; corolla 31--45
mm long; floral bract linear-lanceolate to narrowly triangular, acuminate, 4--7
mm long
- ..........................................C. lanceolatum
- 9b.
- Leaves and flowers glabrous; corolla 21--28 mm long; floral bract deltate, acute,
2--3 mm long
- ..........................................C. oellgaardii
- 2b.
- Calyx limb comparatively inconspicuous, the lobes 1--8 (-10) mm long.
- 10a.
- Calyx continuous with the pedicel; corolla 15--20 mm long
- ..................................................................................C. loranthiflorum
- 10b.
- Calyx articulate with the pedicel; corolla 26 mm long or more.
- 11a.
- Calyx and corolla lobes both provided with circular, concave, black glands
at their bases.
- 12a.
- Leaves concave or margins at least inrolled, 1--2.2 cm long, pilose beneath;
rachis 0.1--0.2 cm long; floral bract without circular gland at base
- ............................................................C. madisoni
- 12b.
- Leaves flat, 2--12 cm long, glabrous beneath; rachis 0.8--7 cm long; floral
bract with or without a circular gland at its base.
- 13a.
- Leaves 2--4 x 1--1.7 cm, the apex obtuse to bluntly acute; inflorescence 4-flowered;
rachis 0.8--0.9 cm long; floral bract with basal, circular gland; pedicel 9--13
mm long; corolla 29--30 mm long
- ...................................................C. glans
- 13b.
- Leaves 6--12 x 2--5.3 cm, the apex sharply acuminate; inflorescence (2-) 5--22-flowered;
rachis 0.8--7 cm long; floral bract without basal, circular gland; pedicel 13--27
mm long; corolla 35--48 mm long
- ...................................................C. ventricosum
- 11b.
- Calyx and corolla lobes normally without basal glands (or glands only present
on either calyx or corolla but not both).
- 14a.
- Leaf venation plinerved.
- 15a.
- Rachis 9--16.5 (-25) cm long; leaves 12--16 x 2--2.5 cm, falcate; calyx hypanthium
bluntly 5-angled, the lobes 5.5--8 mm long, without marginal glandular fimbriae
- ..................................................C. pedunculatum
- 15b.
- Rachis 0.8--8.5 cm long; leaves 2.5--17 x 1.5--6 cm, not falcate; calyx hypanthium
terete, the lobes 1--6 mm long, with marginal glandular fimbriae.
- 16a.
- Calyx lobes apiculate, scarcely 1 mm long, marginally eglandular; floral bract
1 mm long, marginally eglandular; leaves 10--17 cm long
- ..........................................C. prietoi
- 16b.
- Calyx lobes conspicuous, 2--6 mm long, marginally glandular-fimbriate; floral
bract 1.5--4 mm long, marginally glandular-fimbriate; leaves 2.5--12 cm long.
- 17a.
- Leaves 2.5--5 cm long, the margin weakly serrate-crenate; calyx 10--15 mm long,
the lobes 3--6 mm long; corolla (40-) 55--60 mm long, basally not ventricose; rachis
3--6 cm long, pedunculate (i.e., flowering towards tip only)
- .................................C. nubigenum
- 17b.
- Leaves 6--12 cm long, the margin entire; calyx 5--7 mm long, the lobes 2--3.5
mm long; corolla 35--48 mm long, basally ventricose; rachis 0.8--7 cm long, flowering
along entire length
- ...................................C. ventricosum
- 14b.
- Leaf venation pinnate.
- 18a.
- Leaves 7--13.5 cm long, the base acute,
the apex gradually acuminate, the margin flat; staminal filaments free to weakly
connate
- .................................................C. charianthum
- 18b.
- Leaves 2--5 (-8.5) cm long, the base broadly cuneate to rounded (sometimes subcordate),
the apex acute to rounded (rarely acuminate), the margin flat to revolute; staminal
filaments distinct.
- 19a.
- Calyx lobes apiculate, ca 1--2 mm long; leaves revolute and usually marginally
serrate or crenulate
- ..........................................C. alatum
- 19b.
- Calyx lobes conspicuous, 5--8 (-10) mm long; leaves flat to slightly recurved,
the margin entire
- ..........................................C. campii
- 1b.
- Leaves basally conspicuously cordate and usually amplexicual.
- 20a.
- Calyx limb very conspicuous, the lobes 9 mm long or more.
- 21a.
- Calyx hypanthium terete; bracteoles located at apex of pedicel; rachis, pedicel,
calyx, and corolla with glandular-tipped hairs
- ...................................................................................C. pensile
- 21b.
- Calyx hypanthium 5-winged or 10-costate; bracteoles at or below middle of pedicel;
floral pubescence when present of eglandular hairs.
- 22a.
- Calyx hypanthium 5-winged; bracteoles ca 1 mm long.
- 23a.
- Calyx lobes 9--10 mm long, only the margins sparsely ciliate; leaves glabrous
- ............................................................C. auriculatum
- 23b.
- Calyx lobes 20--21 mm long, densely short-pilose within and without; leaves
densely and shortly floccose-tomentose beneath
- ............................................................C. macbrydiorum
- 22b.
- Calyx hypanthium 10-costate; bracteoles (6-) 15--35 mm long.
- 24a.
- Floral bracts (45-) 60--70 mm long, persistent and covering the flowers at anthesis;
bracteoles 35--45 mm long; pedicel 10--12 mm long
- ............................................................C. megabracteatum
- 24b.
- Floral bracts (7-) 10--18 (-35) mm long, caducous, rarely persistent; bracteoles
(6-) 15--25 mm long; pedicel 15--40 mm long
- ............................................................C. peruvianum
- 20b.
- Calyx limb comparatively inconspicuous, the lobes 1--7 mm long.
- 25a.
- Floral bracts 40--70 mm long, persistent, covering the flowers at anthesis
- ..............................................................................C. nodosum
- 25b.
- Floral bracts 2--8 mm long, usually caducous, much shorter than the flowers at
anthesis.
- 26a.
- Inflorescence fasciculate, densely hirsute
- .....................................................................C. lanigerum
- 26b.
- Inflorescence racemose, short-pilose or glabrous.
- 27a.
- Leaves broadly ovate-orbicular, > 9 cm broad, the apex cuspidate to shortly and
sharply acute; calyx hypanthium 5-winged, the lobes apiculate, < 1 mm long; corolla
winged over entire length
- ............................................................C. cutucuensis
- 27b.
- Leaves ovate-elliptic, < 9 cm broad, the apex obtuse to acuminate; calyx hypanthium
essentially terete to conspicuously 10-costate, the lobes 2--7 mm long; corolla
terete not winged.
- 28a.
- Corolla 27--38 mm long; calyx hypanthium cylindric, terete to inconspicuously
10-costate; rachis 0.9--4 cm long, with the pedicel and calyx rather thin and delicate
in appearance; inflorescence 3--8-flowered; floral bracts ca 2--3 mm long, persistent after anthesis; 450--1000 m altitude; south of Baeza (Napo Prov.)
- ...................................................C. silvicola
- 28b.
- Corolla 43--50 mm long; calyx hypanthium turbinate, conspicuously 10-costate;
rachis 5--13 cm long, with the pedicel and calyx thick and coarse in appearance;
inflorescence 5--25-flowered; floral bracts (2-) 5--8 mm long, deciduous; 1350--1900 m altitude; north of Baeza (Napo Prov.)
- ...................................................C. amplexicaule