James L. Luteyn and Paola Pedraza-Peñalosa
The New York Botanical Garden
SPHYROSPERMUM
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Sphyrospermum is a genus of about 21 species of terrestrial and epiphytic
shrubs found in lowland to high montane rainforest habitats from southern
Mexico through the highlands of Central America and the Andes of South
America to Bolivia, east through the Guianas, and in the Caribbean from
Haiti to Trinidad. The center of diversity is found in Colombia and
Ecuador. The genus is characterized by small and obscurely nerved
leaves, solitary or paired sympetalous flowers on usually cernuous pedicels,
inferior ovaries, calyces continuous with the pedicels, staminal filaments
usually longer than anthers, lacking spurs and usually somewhat sigmoid
at the base, anther tubules distinct and as long as or longer than the
thecae with dehiscence by short, oval clefts, and berry fruits which when
immature are dry and brittle. The relationships of Sphyrospermum should be sought with Diogenesia and Themistoclesia;
all three genera have in common corollas usually thin and small, immature
fruits that are thin and brittle, and seeds with green embryos. Sphyrospermum differs from Themistoclesia primarily by its terete not angled calyx,
and from Diogenesia by its fewer flowers on slender, cernuous pedicels
and by filaments longer than anthers. Sphyrospermum has only been
treated in its entirety by Smith (1933b) and that treatment is very much
out of date. The only other major work is that of Luteyn (1996b)
in which the 16 species occurring in Ecuador were revised. |
Most of the species of Sphyrospermum (ca. 12-15 spp.) are extremely rare having only been collected once or a few times; this fact makes the genus a "troublesome" one. The genus as a whole, as well as most of the species, must be considered in extreme danger of extinction, because the localities and habitats in which they have been found are all undergoing severe alteration.
SPHYROSPERMUM Poeppig & Endlicher, Nov. gen. sp.
pl. 1: 4, pl. 8. 1835. Lectotype: Sphyrospermum buxifolium Poeppig & Endlicher.
Sophoclesia Klotzsch, Linnaea 24: 15, 29. 1851. Type: not cited.
Slender, often straggly, epiphytic or terrestrial
shrubs with pendent branches. Leaves alternate, coriaceous, sometimes
very thickly so, often brittle, usually small and obscurely nerved, subsessile.
Inflorescence axillary, flowers solitary or rarely paired in axils of the
leaves; pedicel slender, cernuous, distally swollen; bracteoles
2, deciduous. Flowers 4-5--merous, without odor; aestivation
apparently valvate; calyx continuous with the pedicel; hypanthium
subglobose or obconic; limb suberect; corolla campanulate, cylindric (tubular),
to infundibuliform; stamen usually as many or twice as many as the
corolla lobes, equal or alternately slightly
unequal; filaments distinct, usually longer than anther, lacking spurs,
usually somewhat sigmoid at the base; anther inserted dorsally near base,
membranous, smooth, lacking disintegration tissue; tubules distinct,
as long as or longer than the thecae, dehiscing by oval clefts; pollen
lacking viscin threads; nectariferous disc annular-pulvinate, but
not readily apparent; ovary inferior, 4-5--locular, the partitions
soon decaying; stigma truncate; style filiform, about as long as
corolla. Fruit a subglobose or ellipsoid, juicy berry, topped by
the persistent calyx limb and lobes, translucent white to lavender or purplish,
glabrous or pubescent, when immature the pericarp dry and brittle, when
mature thin and papery; ovules numerous, the placentation axile but
often appearing central or even basal; seeds elongate, striate, the
embryo green and clearly visible through the endosperm. Chromosome
number: 2n=48, 96, ca. 130 (Atkinson et al., 1995).
Key to Neotropical Species Back to Top
1. Corolla tiny, less than 4 mm long.
2. Stamen 4; leaves suborbicular-elliptic,
(1.5-)2-4 cm long; pedicel 5-9 mm long.
3. Leaves
suborbicular-elliptic, 2-4 cm long; pedicels 5-7 mm long; calyx
hypanthium terete, densely villose; corolla 3.5 mm long, weakly pilose
........
...................................................................................................... S. ellipticum.
3. Leaves
ovate to lance-ovate, 4.5-6 cm long; pedicels 7-15 mm long;
calyx hypanthium slightly 4-angled, glabrous but glandular-fimbriate;
corolla 2-2.3 mm long, glabrous (?) ................................................ S. standleyi.
2. Stamen 8-10; leaves orbicular
to ovate-elliptic, 0.5-1.3 x 0.4-0.8 cm;
pedicel to 4
mm long.
4. Flowers
5-merous, subsessile, pedicel less than 1 mm long; corolla hispid
in distal 1/2-1/3, cylindric-campanulate, the throat open and spreading;
leaves 10-13 x 6-8 mm ........................................................... S. spruceanum.
4. Flowers
4-merous, obviously pedicellate, pedicel 3-6 mm long; corolla
glabrous, cylindric, the throat narrowed and contracted; leaves 5-8
x 4-6
mm long ................................................................................ S. microphyllum.
1. Corolla larger, equal to or greater than 4 mm long (if 4 mm
long, then pedicel
> 15 mm long).
5. Corolla campanulate, the throat broad
and spreading.
6. Corolla
yellow, ca. 5-5.5 mm long; anther tubules much longer than
thecae, dehiscing by oblique, subterminal pores .......................... S. flaviflorum.
6. Corolla
dark red, 8.5-12 mm long; anther tubules equal to or shorter
than thecae, dehiscing by perfectly terminal pores.
7. Flowers 4-merous; pedicel 1-4(-8) mm long; leaves
apically acute
to rounded; anther tubules about equalling thecae, ca.1.6-2.5 mm
long;
berry quadrangular .................................................................. S. dissimile.
7. Flowers 5-merous; pedicel 10-15 mm long; leaves apically
obtuse-
mucronate; anther tubules < thecae, ca. 0.5-0.6 mm long;
berry ellipsoid
....................................................................................... S. campanulatum.
5. Corolla cylindric to cylindric-urceolate
or cylindric-infundibuliform, the
throat obviously
contracted.
8. Corolla
equal to or greater than 12 mm long, the lobes strongly reflexed at
anthesis so as to expose stamens (mature corolla unknown in S. musicola).
9. Leaves pellucid, veinlets clearly visible, very acute at apex,
about as long
as broad, 20-30 x 20-23 mm; stamen 10, with filaments slightly longer
than anthers; calyx lobes ca. 1.5 mm long, tufted-pilose at tip;
pedicel
15-20 mm long; corolla red, pilose distally, 12-20 mm long
... S.
musicola.
9. Leaves coriaceous, opaque, veinlets obscure, long- to short-acuminate
at apex, noticeably longer than broad; stamen 8-10, with filaments
about two times anther length.
10. Leaves narrowly ovate-lanceolate, very long-acuminate;
flowers
5-merous; E Ecuador ................................................ S. lanceolatum.
10. Leaves ovate to broadly ovate, short- to long-acuminate;
flowers 4-merous; W Ecuador.
11. Leaves 1-3.5(-4.3) x 0.5-1.5(-1.8) cm; corolla infundibuliform,
moderately to densely short-hirsute; filaments 13-15 mm long,
densely pilose; flowers conspicuously extending beyond the
subtending leaf; calyx densely to sparsely puberulent ... S.
boekei.
11. Leaves (2.6-)3-7(-8.5) x (1.6-)2.5-3.5 cm; corolla tubular,
broadened above middle, usually glabrous; filaments 9-15 mm
long, usually glabrous; flowers not extending beyond but instead
usually slightly hidden by the subtending leaves; calyx usually
glabrous ............................................................ S. grandifolium.
8. Corolla
equal to or less than 12 mm long, the lobes not so strongly reflexed
as to expose stamens at anthesis.
12. Pedicel 0-10 mm long, the flowers ± hidden by the leaves.
13. Pedicel none, the flowers sessile.
14. Leaves distichous, 6-11 x 4-9 mm, ovate with the apex
obtuse to acute; corolla 5 mm long, pilose in distal half;
twigs hispid with ferrugineous hairs; Colombia ..... S.
distichum.
14. Leaves spirally arranged, 15-21 x 4-6 mm, lanceolate with
the apex acuminate; corolla 8.5-10 mm long, weakly pilose;
twigs densely white pilose; Bolivia ................... S.
sessiliflorum.
13. Pedicel 4-10 mm long, the flowers pedicellate.
15. Calyx lobes 2-2.5 mm long; corolla pubescence glandular
.....
................................................................................. S. buesii.
15. Calyx lobes equal to or less than 1 mm long; corolla glabrous
or if pubescent, then the hairs non-glandular.
16. Corolla tubular, broadest above the middle, 9-12 mm
long, hispid, red with lobes blue-black (even when dry);
leaves 1-3 cm long, succulent and brittle when fresh but
drying thin-coriaceous with the lower surface strongly
wrinkled; calyx hispid, the lobes acuminate, 0.6-0.8 mm
long; stamen alternately unequal, the filaments longer than
anthers, 5.5-7.5 mm long .................................. S.
sodiroi.
16. Corolla urceolate, ca. 6 mm long, glabrous, pale yellow,
the lobes not black; leaves (2-)2.5-4 cm long, succulent
when fresh and drying thick-coriaceous, concave, often
revolute, and with the midrib often strongly carinate;
calyx short white pilose to villous, the lobes deltate,
short-acuminate, 0.6-1 mm long; filaments shorter than
anthers, 1-1.5 mm long ................................... S.
haughtii.
12. Pedicel (10-)12-25 mm long.
17. Leaves suborbicular, (0.7-)0.9-1.5(-1.8) cm long, the apex
rounded; flowers extending well beyond the leaves; mature
corolla 4-5.5 mm long (rarely 6 mm), white to pinkish;
stamens 4 ................................................................. S. buxifolium.
17. Leaves ovate to ovate-lanceolate, usually conspicuously longer
than broad, (1-)2-13 cm long, the apex obtuse to sharply long-
acuminate; flowers rarely extending beyond the leaves; mature
corolla 5-12 mm long (rarely less), white to dark red; stamens
4-5 or 8-10.
18. Leaves ovate-lanceolate, (8-)10-13 x 4-5 cm, the apex
(usually sharply) long-acuminate; corolla ca. 9.5 mm long;
stamens 10 ...................................................... S. longifolium.
18. Leaves broadly to narrowly ovate, (1-)2-3.5(-5) x (0.8-)
1.5-6 cm, the apex obtuse to long-acuminate; corolla
(4-)5-12 mm long; stamens 4-5 or 8-10.
19. Leaves 4-6 x 1.2-2 cm, the apices long-acuminate;
corolla 10-12 mm long; stamens 8 or 10; staminal
filaments glabrous; Peru ......................... S.
weberbaueri.
19. Leaves (1-)1.5-3.5(-5) x 0.7-2.5(-3) cm, the apex
obtuse or rounded to acute, sometimes shortly and
bluntly acuminate; corolla (4-)5-8(-9) mm long;
stamens 4-5 or 8-10; staminal filaments glabrous or
pilose.
20. Flowers glabrous or more normally pilose; fruits
globose to thickly fusiform, to15 mm diam;
Mexico to Bolivia, E to the Guianas and
Hispaniola ........................................ S.
cordifolium.
20. Flowers glabrous; fruits ellipsoid, 4-6 mm long
and 2.5-4 mm broad.
21. Corolla 5-6 mm long, bright yellow, densely
pilose within; filaments about equal to the
anthers and callose-thickened at base;
Colombia ........................... S.
munchiqueensis.
21. Corolla ca. 8 mm long, white, glabrous within;
filaments longer than anthers and not basally
callose-thickened; Mt. Roraima, Venezuela ...
............................................. S.
klotzschianum.
A species of uncertain status keys here: Sphyrospermum
tuberculatum
Wilbur & Luteyn (perhaps it is just S. cordifolium, but with
tuberculate
calyces.