Systematics of the Octopleura Clade of Miconia (Melastomataceae: Miconieae) in Tropical America
Author
Gamba, Diana
Institute for Biodiversity Science and Sustainability, Department of Botany, California Academy of Sciences, 55 Music Concourse Drive, Golden Gate Park, San Francisco, CA 94118 - 4503, USA; & dgamba 333 @ gmail. com,
dgamba333@gmail.com
Author
Almeda, Frank
Institute for Biodiversity Science and Sustainability, Department of Botany, California Academy of Sciences, 55 Music Concourse Drive, Golden Gate Park, San Francisco, CA 94118 - 4503, USA; & falmeda @ calacademy. org & Institute for Biodiversity Science and Sustainability, Department of Botany, California Academy of Sciences, 55 Music Concourse Drive, Golden Gate Park, San Francisco, CA 94118 - 4503, USA; & dgamba 333 @ gmail. com,
falmeda@calacademy.org
text
Phytotaxa
2014
2014-09-24
179
1
1
174
journal article
10.11646/phytotaxa.179.1.1
1179-3163
10089927
14.
Miconia erikasplundii
Gamba & Almeda
,
nom. nov.
Basionym:
Clidemia asplundii
Wurdack (1973a: 404–405)
. Type:
ECUADOR
. Prov.
Morona-Santiago
(Santiago-Zamora on original label): Macas, wooded bank of the Río Upano, ca.
800 m
,
18 March 1956
,
Asplund 19806
(
holotype
: S!). Nec
Miconia asplundii
Wurdack (1972: 202–203)
.
Slender shrub or small tree to
3 m
tall, commonly sparingly branched.
Upper internodes
[
3–15.4 cm
long] and cauline nodes terete, nodal line absent.
Indumentum
on branchlets, petioles, inflorescence axes, bracts, and bracteoles densely and copiously composed of resinous sessile dendritic trichomes
0.1–0.2 mm
in diameter with short axes and few-moderate number of terete arms.
Leaves
of a pair conspicuously anisophyllous (2:3–6); the terete petiole
1.9–2.95 cm
long, (on larger leaves) or
0.58–1.41 cm
long (on smaller leaves), slightly canaliculate adaxially from the primary leaf vein throughout its entire length; larger blades 13.5–20.4 ×
8.9–13.8 cm
, ovalorbicular, the base rounded-obtuse, the margin distantly undulate-serrulate, the apex bluntly acuminate; smaller blades 6.9–12.2 ×
6.6–10.3 cm
, orbicular, the base rounded to slightly cordate, the margin distantly undulateserrulate, the apex shortly and bluntly acuminate; membranaceous; adaxial surface of mature leaves glabrous except for a few sessile-stellate trichomes at the base of the blade, the primary, secondary, tertiary and higher order veins glabrous; abaxial surface glabrous except for a few sessile-stellate trichomes coming from the venules, the primary, secondary, tertiary and higher order veins densely to copiously covered with resinous sessile-stellate trichomes
0.25–0.3 mm
in diameter; 5-(7-)nerved (larger leaves) or 5-nerved (smaller leaves), including the tenuous marginals, with a thick-callose vesicular structure formed at the blade base abaxially where the innermost pair of secondary veins diverge from the primary vein, areolae
0.2–0.3 mm
, adaxially the primary, secondary, tertiary and higher order veins conspicuously impressed, abaxially the primary and secondary veins elevated and terete, the tertiary and higher order veins slightly elevated.
Inflorescences
a pseudolateral dithyrsoid (6–)
7–10 cm
long, including a peduncle
1.6–2.8 cm
long, divaricately branched from the peduncle apex, the dendritic indumentum on the axes sparse and densely intermixed with resinous sessile-stellate trichomes
0.25–0.3 mm
in diameter; bracts 0.5–0.6 ×
0.25 mm
, oblong-obovate, somewhat erect, deciduous in fruit; bracteoles 1–1.5(–2.5) ×
0.3 mm
, oblong-obovate, patent, persistent in fruit.
Flowers
4-merous on pedicels
0.5–0.8 mm
long, densely to copiously resinous with slightly furrowed more or less stalked glands to
0.1 mm
long.
Hypanthia
at anthesis
SYSTEMATICS OF THE
OCTOPLEURA
CLADE OF
MICONIA
Phytotaxa
179 (1) © 2014 Magnolia Press
75
2.8–2.9 ×
1.7–1.9 mm
, free portion of hypanthium
1–1.2 mm
long, urceolate, bluntly 8-ribbed, densely to copiously resinous with slightly furrowed more or less stalked glands to
0.1 mm
long, ridged inside, the inner vestiture not seen, torus adaxially not seen.
Calyx
open in bud and persistent in fruit; tube
0.2 mm
long, the calyx lobes and exterior calyx teeth copiously resinous-glandular like the hypanthium, inner surface and vestiture not seen; lobes 0.35 ×
0.8–0.9 mm
, ovate, the margin entire, the apex rounded; exterior calyx teeth
0.2 mm
long, ovate and thick, inserted near the base of the calyx lobes, divergent but not projecting beyond the lobes.
Petals
1.6 ×
1.6–1.7 mm
, suborbicular, the margin entire, the apex rounded, white, densely papillose on both surfaces, reflexed at anthesis.
Stamens
8; filaments 1.5–1.6 ×
0.2 mm
, white, glabrous; anther thecae 1.9 ×
0.25 mm
, linear-oblong and slightly subulate, obtuse at the apex, opening by one dorsally inclined pore
0.1 mm
in diameter, yellow at anthesis; connective darker than the thecae, its prolongation and appendage
0.35–0.4 mm
long, the appendage oblong to deltoid, rounded at the apex, copiously gland-edged, the glands subsessile, minute, rounded and distributed throughout the connective and its prolongation.
Ovary
4-locular, completely inferior,
1.7–1.8 mm
long at anthesis, apical collar absent, the apex
0.35–0.4 mm
in diameter, slightly depressed, moderately glandularpuberulent; style
5.5–6 mm
long, parallel sided (i.e. terete), white, glabrous; stigma truncate to expanded-truncate when dry.
Berries
3.55–4.55 ×
4.05 mm
when dry, globose and slightly oblate, ripening red and probably becoming blue-purple when fully mature, the hypanthium indumentum more or less persistent at maturity.
Seeds
0.29–0.33 ×
0.14–0.15 mm
, ovoid, angled, light brown; lateral and antiraphal symmetrical planes ovate, the highest point toward the chalazal side or near the central part of the seed; raphal zone suboblong, as large to 50% larger than the corpus of the seed, extending along its entire length, ventrally and longitudinally expanded, dark-brown; individual cells elongate, anticlinal boundaries inconspicuously channeled and undulate; periclinal walls nearly flat, microrelief punctate.
Additional specimens studied:—
Only the
type
was available for study.
Illustration:—
None found.
Common names and documented uses:—
None recorded.
Habitat, distribution and ecology:—
Miconia erikasplundii
is endemic to eastern
Ecuador
where it is only known from near
Tena
(
Napo Province
) and from the banks of the
Río Upano
near
Macas
(
Morona-Santiago Province
) (
Fig. 14
) at
600–800 m
. It occurs in the understory of riparian tropical forests along river banks. In its restricted range, it is considered a rare species
.
Phenology:—
The
holotype
was collected in flower and fruit in March.
Etymology:—
The specific epithet commemorates the Swedish botanist Erik Asplund (1888–1974) who botanized in Andean South America. He collected in
Ecuador
,
Perú
and
Colombia
in 1939–1940, and again in
1955–1956 in
Ecuador
,
Perú
and
Venezuela
. The first set of his collections are deposited at S.
Discussion:—
Miconia erikasplundii
is more similar to
M. biolleyana
in the anisophylly and leaf shape, but the vegetative pubescence of
M. biolleyana
consists of only sessile-stellate trichomes, with none of the peculiar resinous-asperous dendritic trichomes present in
M. erikasplundii
. Furthermore, the vestiture of hypanthia and calyx teeth is clearly different. In
M. biolleyana
it consists of the same arachnoid vegetative tomentum of sessilestellate trichomes (vs. resinous-glandular in
M. erikasplundii
). The rest of the floral characters (petals, stamens and style) are similar in the two species.
The current geographic ranges of
M. biolleyana
and
M. erikasplundii
do not overlap, the former is not known from
Ecuador
. It is known from
Costa Rica
,
Panama
and as far south as the department of
Risaralda
in
Colombia
.
Conservation status:—
Endangered EN B2ab(iii). It was considered Vulnerable in past assessments (
Cotton & Pitman 2004
). This Ecuadorian endemic is known only from three collections. The most recent is from 1960. It has not been collected in any of Ecuador’s protected areas but it could potentially occur in the Sangay National Park. Apart from habitat destruction, no specific threats are known.