Conostegia dissitiflora
Miconia dissitiflora
A Monograph of Conostegia (Melastomataceae, Miconieae)
Kriebel, Ricardo
PhytoKeys
2016
2016-07-20
67
1
326
61483388-1EE5-5FB2-9B52-9D7BB7F21BD5
(Almeda) Kriebel
Kriebel
2016
Kriebel
2016
Magnoliopsida
Melastomataceae
Conostegia
CoL
Plantae
Conostegia dissitiflora
Myrtales
161
162
Tracheophyta
species
dissitiflora
comb. nov.
Conostegiadissitiflora(Almeda) Kriebel. Basionym: Miconia dissitifloraAlmeda, 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 x1.3-10 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 inbud 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 x1.5-1.75 mm, hypanthium 1.5-1.85 x1.5-1.65 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 x1.5-2 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 x0.5 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 x3-4 mm, purple black. Seeds 0.36-0.7 mm, mostly ovoid, with densely muricate or verrucose testa. Figure 149. Conostegia dissitiflora. AHabit BLeaf adaxial surface CClose up of a flower DBerry. Photos of Aand Cof specimen vouchered R. Kriebel 5070, and B, Dvouchered 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 dissitiflorais 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 threeflowering 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 cinnamomeawhich 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 dissitiflorain Cogniaux'ssections 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, Peninsulade Osa, RioTigre, Quebrada Pizote, Azofeifa 783 (INB, NY); R. F. Golfo Dulce, Peninsulade Osa, Puerto Jimenez, RioNuevo, Kriebel et al. 5070 (INB, NY); Peninsulade Osa, Guadalupe La Tarde, Kriebel et al. 5378 (INB).