A Monograph of Conostegia (Melastomataceae, Miconieae)
Author
Kriebel, Ricardo
Department of Botany, University of Wisconsin-Madison, 430 Lincoln Drive Madison, Wisconsin 53706, USA
kriebelr@gmail.com
text
PhytoKeys
2016
2016-07-20
67
1
326
http://dx.doi.org/10.3897/phytokeys.67.6703
journal article
http://dx.doi.org/10.3897/phytokeys.67.6703
1314-2003-67-1
D846EB3F7746FFFE4A469751FFEF3B22
133270
Conostegia dissitiflora (Almeda) Kriebel
comb. nov.
Fig. 149
Conostegia
dissitiflora
(Almeda) Kriebel. Basionym:
Miconia dissitiflora
Almeda, Proc. Calif. Acad. Sci, series 4, 46(5): 146, f. 5. 1989. Type: Costa Rica. Puntarenas: above Golfito along road to television tower, elev. 50-500 m, 16 Jul 1977, F. Almeda, Wilbur, R. and T. Daniel 3093 (holotype: CAS!, isotypes: BM, BR, CR!, DUKE, F!, MO!, NY!, US!).
Description.
Sparingly branched shrub 1-3 m tall with terete and glabrous internodes; the distal branches moderately to sparingly stellate-furfuraceous; the nodal line present. Leaves of a pair somewhat unequal in size, sessile and clasping or with petioles 1-9 mm long. Leaf blade 4-22
x
1.3-10 cm, 5-7 plinerved, with the innermost pair of veins diverging 0.4-3.5 cm above the blade base in sub opposite or alternate fashion, elliptic to elliptic ovate, the base rounded to subcordate and sometimes oblique, the apex acuminate, the margin undulate-dentate to subentire, adaxially glabrous, abaxially glabrous or with some stellate hairs on the elevated primary veins. Inflorescence a terminal, erect or reflexed divaricately branched, paniculiform dichasium, 6.4-20.5 cm long, branching at or above the base, accessory branches absent, branches glabrescent, thin and wiry, bracteoles paired, sessile and fused into a short nodal collar forming an elevated internode ridge, 0.5 mm long, lance triangular to subulate, persistent. Pedicels 1.5-2.5 mm long. Flowers 5 merous, calyx in bud not calyptrate but closed
in
bud and crowned by an apiculum, rupturing irregularly at anthesis into 2-5 hyaline lobes 1-1.5 mm long. Flower buds 1.75-2.25
x
1.5-1.75 mm, hypanthium 1.5-1.85
x
1.5-1.65 mm, campanulate, glabrous to stellate puberulent, calyx tube ca. 0.5 mm long, the calyx teeth subulate, 0.5 mm long. Petals 3.25-3.75
x
1.5-2 mm, translucent white, oblong-lanceolate, reflexed at anthesis, the apex acute to retuse, glabrous. Stamens 10, alternately unequal with the larger stamens inserted on the torus opposite the petals and the small ones opposite the calyx lobes, radially arranged around the style, the filaments 1.5-2 mm, with a geniculation near the apex, white, anthers 1.5-2
x
0.5 mm, linear-oblong, yellow, laterally compressed, the pore 0.15 mm, somewhat dorsally inclined. Ovary 5-locular, inferior, minutely puberulent at the apex. Style 2.5-3 mm, straight, vertical distance from the anther to the stigma 1.25-1.5 mm, horizontal distance absent, stigma truncate, 0.3-0.5 mm wide. Berry 3-4
x
3-4 mm, purple black. Seeds 0.36-0.7 mm, mostly ovoid, with densely muricate or verrucose testa.
Figure 149.
Conostegia dissitiflora
.
A
Habit
B
Leaf adaxial surface
C
Close up of a flower
D
Berry. Photos of
A
and
C
of specimen vouchered
R. Kriebel 5070
, and
B, D
vouchered
R. Kriebel 5378
.
Distribution
(Fig.
150
). Endemic to south Pacific Costa Rica, mainly in the Golfo Dulce region and the Osa Peninsula but also towards to mountains on the road from San Vito de Coto Brus to Ciudad Neily, from sea level to 660 m elevation.
Figure 150.
Distribution of
Conostegia dissitiflora
.
Conostegia dissitiflora
is a distinctive species on the basis of its overall glabrous, plinerved, sessile leaves, and 5-merous flowers with an irregularly rupturing calyx.
Almeda (1989a)
discussed an unusual feature of this species which is the presence of
"anisomorphic"
stamens, with the larger set of stamens positioned opposite the petals. The
three
flowering populations observed had flowers with exserted styles as is common in section
Geniculatae
. Interestingly, when
Almeda (1989a)
described this species, he compared it to
Conostegia cinnamomea
which it falls very close to in the molecular phylogeny. The two share almost complete glabrosity and plinerved venation.
Almeda (1989a)
discussed similar problems in placing
Conostegia dissitiflora
in
Cogniaux's
sections as he encountered placing
Conostegia calocoma
. The problems arose because staminal characters including anther shape and lack of stamen appendages suggested section
Amblyarrhena
, but a fused calyx suggested section
Laceraria
.
Specimens examined.
COSTA RICA
.
Puntarenas
: Sierpe, Reserva Forestal Golfo Dulce,
Rincon
, cerca de la desembocadura del
Rio
Rincon
, Aguilar 11413 (NY); R. F. Golfo Dulce,
Peninsula
de Osa,
Rio
Tigre, Quebrada Pizote, Azofeifa 783 (INB, NY); R. F. Golfo Dulce,
Peninsula
de Osa, Puerto
Jimenez
,
Rio
Nuevo, Kriebel et al. 5070 (INB, NY);
Peninsula
de Osa, Guadalupe La Tarde, Kriebel et al. 5378 (INB).