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
11.
Miconia boekei
(
Wurdack 1978b: 9–10
)
Gamba & Almeda
,
comb. nov.
Basionym
:
Ossaea boekei
Wurdack.
Type
:
ECUADOR
. Prov.
Azuay
:
Jesús María–Molleturo
road, about
10 km
from
Guayas
border,
ca.
1100 m
,
16 July 1977
,
Boeke
&
Loyola
2171
(
holotype
: US!; isotypes: MO!, NY-internet image!).
Subshrub or shrub (1.5–)
3–5 m
tall, sparingly branched.
Upper internodes
compressed-rounded, (1–)
5.7–8.4 cm
long, cauline nodes terete, nodal line absent.
Indumentum
on branchlets, petioles, primary and secondary leaf veins abaxially, inflorescence axes, bracts, bracteoles, pedicels, hypanthia, calyx lobes abaxially, and exterior calyx teeth copiously covered with whitish elongate moderately roughened trichomes to
1 mm
long, each trichome claviform and somewhat thickened, copiously intermixed with a whitish understory of single-tiered lepidote trichomes
0.15–0.23 mm
in diameter with the radii nearly completely fused.
Leaves
of each pair typically equal in size; petiole
2–3 cm
long, canaliculate and depressed adaxially, quadrate-grooved abaxially; blades 18–30 ×
7–13 cm
, elliptic, the base acute, the margin obscurely undulate-serrulate, the apex shortly to abruptly acuminate, chartaceous; mature leaves adaxially with surface and primary vein at first sparsely covered with the whitish lepidote general trichomes but soon becoming glabrous, the secondary, tertiary and higher order veins glabrous; abaxial surface, essentially glabrous with age, with caducous lepidote trichomes similar to those on the adaxial surface, the tertiary and higher order veins sparsely beset with short-stalked glands
0.1 mm
long with thin-walled short heads to glabrescent; 5-plinerved, including the tenuous marginals, innermost pair of secondary veins diverging asymmetrically from the primary vein
1.5–3 cm
above the base, areolae
0.5–0.7 mm
, adaxially the primary and secondary veins slightly impressed, the tertiary and higher order veins flat, adaxially the primary and secondary veins elevated and terete toward the base, the tertiary and higher order veins flat.
Inflorescences
an axillary dithyrsoid
5–8 cm
long, including a peduncle
0.5–1 cm
long, occasionally the lateral branches of the
SYSTEMATICS OF THE
OCTOPLEURA
CLADE OF
MICONIA
Phytotaxa
179 (1) © 2014 Magnolia Press
67
dichasia with secund flowers, divaricately branched from the peduncle apex, paired among the upper leaves; bracts and bracteoles 1.5–2 ×
1.8–2.2 mm
, broadly ovate, the margins sparsely denticulate, acute to aristulate at the apex, concave, with conspicuous parallel venation, the indumentum caducous, the bracts somewhat spreading, the bracteoles erect, occasionally alternately positioned along the inflorescence branchlets, both persistent in fruit.
Flowers
5-merous, subsessile or on pedicels
0.3–2 mm
long.
Hypanthia
at anthesis 2.3–2.9 ×
2–2.2 mm
, free portion of hypanthium
0.9–1.2 mm
long, subcylindric becoming globose in fruit, obscurely 10-ribbed, ridged on the inner surface, glabrous, the torus sparsely and minutely resinous-glandular adaxially.
Calyx
open in bud and persistent in fruit; tube
0.3–0.5 mm
long, with the same vestiture as the torus adaxially and as the hypanthium abaxially; lobes 0.5–0.7 ×
0.8–1 mm
, oblong-triangular, the margin entire, the apex bluntly acute, glabrescent abaxially; exterior calyx teeth to
1 mm
long at anthesis, conic-thick, inserted inframarginally and not projecting beyond the lobes.
Petals
5–5.8 ×
1.7–2.1 mm
, oblong-lanceolate, the margin entire, the apex acute, cream to white, glabrous adaxially, abaxially with a copious squamate-stellate central band of lepidote trichomes with only partially fused radii, reflexed at anthesis but often appearing somewhat erect when dry.
Stamens
10; filaments 2–2.5 ×
0.25 mm
, white, glabrous; anther thecae 1.5–2 ×
0.5–0.7 mm
, oblong, somewhat clavate and emarginate at the apex, opening by two dorsally inclined pores
0.15 mm
in diameter; connective darker than the thecae when dry, its prolongation and appendage
0.3–0.5 mm
long, the appendage deltoid to somewhat spatulate, obtuse-rounded at the apex, copiously gland-edged, the glands conspicuously stalked and rounded, the stalks linear to subulate to
0.2 mm
long, the connective also somewhat prolonged and gland-edged but unappendaged ventro-basally.
Ovary
(6-) 7-locular, completely inferior,
1.4–1.7 mm
long at anthesis, the apical collar absent, the apex
0.25 mm
in diameter, truncate, sparsely glandular-granulose; style
6.5–7 mm
long, narrowed distally (i.e. tapering), white, glabrous; stigma truncate to expanded truncate at anthesis.
Berries
4–4.3 ×
5–5.2 mm
when dry, globose and slightly oblate, initially pale green, ripening orange, the hypanthial indumentum persistent at maturity.
Seeds
0.43–0.48 ×
0.17–0.2 mm
, ovoid, angled, brownish; lateral and antiraphal planes ovate, the highest point toward the chalazal side; raphal zone sublinear, nearly as long as the seed, somewhat ventrally expanded toward the micropyle; appendage absent but a small protuberance may be present; individual cells elongate, anticlinal boundaries channeled, undulate, with Ω- and U-type patterns; periclinal walls convex, low-domed to nearly flat, microrelief inconspicuously striate.
Additional specimens studied:—
ECUADOR
.
Azuay
/
Cañar
:
Manta Real
,
Río Patul
, Sde la carretera
La Troncal-Zhud
, camino
entre Zhucay y Río Patul
en la base de los
Andes
,
Trocha
subiendo el piedemonte hasta
1200 m
, atrás (E) del pueblo
Manta Real
,
2°33’S
,
79°20’W
,
450–800 m
,
13 July 1991
,
Foster
&
Mitsui
13553
(F,
QCA
)
.
El Oro
:
Hacienda Buanventura
,
12 km
W Piñas
on road to
Machala
,
3°48’S
,
79°46’W
,
900 m
,
25 February 1991
,
Kessler
2553
(
US
)
.
Esmeraldas
:
(
Quininde
),
Estación Biológica Bilsa
,
Carretera
Herrera-El
Páramo
(
Sat
,
Isabel
),
0°21’36"N
,
79°42’40.4"W
,
580 m
,
18 February 1995
,
Palacios
et al. 13565
(
MO
); (
Quininde
)
,
Estación Biológica Bilsa
,
Carretera
Herrera-El
Páramo
(
Sat
,
Isabel
),
0°21’36"N
,
79°42’40.4"W
,
580 m
,
18 February 1995
,
Palacios
et al. 13572
(
MO
); (
Quininde
)
,
Mache-Chindul Ecological
R.,
Bilsa Biological Station
,
Mache Mountains
,
35 km
Wof Quinindé
,
Ramon Loor's
property,
0°21’N
,
79°44’W
,
500 m
,
22 October 1996
,
Clark
3076
(
MO
)
;
R.B.
Bilsa
,
Sendero Amarillo
,
0°20’49"N
,
79°42’41"W
,
540 m
,
13 February 2009
,
Stern
&
Tepe
399
(
CAS
); (
Quininde
)
,
Bilsa Biological Station
,
Montañas
de Mache
,
35 km
Wof
Quinindé
,
5 km
Wof
Santa Isabel
,
Nbearing
border of R., between the
Station
road and the E-bearing border crossing the
Río Cube
,
0°21’N
,
79°44’W
,
400–600 m
,
23 September 1994
,
Baas
&
Clark
59
(
MO
); (
Quininde
)
,
Mache-Chindul Ecological
R.,
Bilsa Biological Station
,
Mache Mountains
,
35 km
Wof Quinindé
,
5 km
Wof
Santa Isabel
,
Near
permanent plot #1,
0°21’N
,
79°44’W
,
500 m
,
6 February 1996
,
Clark
et al. 1960
(
MO
,
QCNE
,
US
)
.
Los Ríos
:
(
Quevedo
),
Cerro Centinela
, el
Mirador
, A
12 km
al Ede
Patricia Pilar
y
Centro Cientifico Río Palenque
,
0°37’S
,
79°18’W
,
540 m
,
3 June 1990
,
Rubio
&
Alverson
410
(
QCNE
,
US
)
.
Los Ríos-Pichincha
:
Path
following ridge line at
El Centinela
at crest of
Montanas
de Olla
on road from
Patricia Pilar
to 24
de Mayo
at km 12,
Patricia Pilar
is at km 45 on road from
Sto Domingo
to
Quevedo
,
600 m
,
28 July 1979
,
Dodson
et al. 8611
(
MO
,
US
)
;
Path
following ridge line at
El Centinela
at crest of
Montanas
de Olla
on road from
Patricia Pilar
to 24
de Mayo
at km 12,
Patricia Pilar
is at km 45 on road from
Sto Domingo
to
Quevedo
,
600 m
,
6 February 1979
,
Dodson
7390
(
MO
)
.
Illustration:—
None found.
Common names and documented uses:—
None recorded.
Habitat, distribution and ecology:—
Endemic to
Ecuador
where it is rare in primary or secondary cloud and premontane wet forests and disturbed sites throughout the western foothills of the Ecuadorean Andes (
Fig. 13
), at
400–1100 m
.
68
Phytotaxa
179 (1) © 2014 Magnolia Press
GAMBA & ALMEDA
Phenology:—
Collected in flower and fruit in February, from June through July, and from September through October.
Etymology:—
The specific epithet is dedicated to the collector of the
type
, Jef D. Boeke, a molecular biologist and geneticist, currently at the Johns Hopkins University School of Medicine in Baltimore,
Maryland
,
United States
.
Discussion:—
This species is readily recognized by the dense claviform-thickened vegetative indumentum that also covers the hypanthium and calyx, markedly asymmetrical plinervation, and conspicuous bracteoles that are occasionally present subalternately around the ultimate dichasial branching of the inflorescence. In the protologue, Wurdack suggested that it is closest is
M. variabilis
, a species with somewhat similar foliar plinervation and laxly reticulate and elevated foliar veins abaxially. Apart from the deflexed gland-edged dorso-basal staminal connective appendage and the conspicuous hypanthial ribs (synapomorphies for the entire
Octopleura
clade); these two species do not seem to have much else in common morphologically.
Miconia boekei
is sister to
M. neomicrantha
(
Fig. 1
), a species with very different vegetative indumentum and overall general appearance. Another close relative is
M. albertobrenesii
, as noted by
Wurdack (1978b)
, which differs in having shorter vegetative and floral indumentum, foliar areoles more densely arranged (
0.2–0.3 mm
in
M. albertobrenesii
vs.
0.5–0.7 mm
), plinervation asymmetrical but less striking (
0.6–1.2 cm
vs.
1.5–3 cm
), and different berry color at maturity (white vs. orange). Both
M. albertobrenesii
and
M. boekii
have a similar anther shape (rather clavate-emarginate) and ovaries that are occasionally 6-locular.
Based on available collections, the northernmost occurrence of this species is in the southwest part of the
Esmeraldas province
. The southernmost is in the central-south of
El Oro province
. This distribution suggests that the range of this species is definitely centered in
Ecuador
, because the aforementioned points are far removed from the Colombian and Peruvian borders.
Conservation status:—
Endangered EN B2ab(iii). It was considered Vulnerable in previous assessments (
Cotton & Pitman 2004
). In northern
Ecuador
, at least one population is protected inside the Reserva Ecológica Mache-Chindul (
Esmeraldas
). Three specimens are housed in Ecuadorian herbaria:
Clark et al. 1960
(QCNE),
Foster & Mitsui 13553
(QCA),
Rubio & Alverson 510
(QCNE). Habitat destruction is the only known threat.