Conostegia plumosa L.O. Williams, Fieldiana

Kriebel, Ricardo, 2016, A Monograph of Conostegia (Melastomataceae, Miconieae), PhytoKeys 67, pp. 1-326 : 210-211

Conostegia plumosa L.O. Williams, Fieldiana

Conostegia plumosa L.O. Williams, Fieldiana, Bot. 29: 562. 1963. Type: British Honduras [= Belize]. Middlesex: 200 ft elev, 10 July, 1929, W. Schipp 232 (holotype: F!, isotypes: A, CAS!, GH, MO!, US!).

Description.

Trees 2.7-15 m tall with flattened branches which soon become terete and are covered with stellate and dendritic hairs in younger parts; the nodal line inconspicuous. Leaves of a pair equal to somewhat unequal in length. Petiole 0.9-4.5 cm. Leaf blade 6-21 × 2-6 cm, 3-5 plinerved, with innermost pair of veins diverging from the midvein above the base in opposite or alternate fashion, elliptic to elliptic ovate, the base acute to attenuate, the apex acute to acuminate, the margin serrulate, the adaxial surface stellate pubescent when young and glabrous with age, the abaxial surface tan to white color from the stellate and plumose hairs. Inflorescence a terminal panicle 3.3-12 cm long, the rachis covered with stellate and plumose hairs, linear, the bracteoles 2-8 mm long, deciduous. Pedicel absent or to 0.5 mm. Flowers 6 merous, calyptrate. Floral buds 4-6 × 2.4-3.25 mm, ovoid, the base rounded, the apex obtuse, slightly constricted in the middle, with six linear appendages ca. 2.5 mm long appressed to the top of the calyptra. Hypanthium 2.5-3 × 3-3.25 mm, with stellate and plumose hairs. Petals 4-6 × 1.5-2 mm, white, spathulate, spreading, glabrous. Stamens 12(-13), 4.25-5.5 mm long, the filament 2-2.5 mm long, white, the anthers 2.25-2.75 × 0.5-0.75 mm, linear-oblong and somewhat recirved, yellow, the pore 0.1-0.2 mm in diameter, subterminal. Ovary 6 locular, inferior, the apex glabrous and forming an irregular collar around the style. Style 3.5-6 mm, apparently straight, distance between the anthers and stigma ca. 0-1 mm, stigma truncate, 0.35-0.65 mm wide. Berry 5-6 × 5-6 mm, purple-black. Seeds 0.65-1.2 mm, obliquely pyramidal, the testa angulate and smooth.

Distribution

(Fig. 185 ). Belize, Guatemala, Honduras and in Chiapas in Mexico, at 50-1000 m in elevation.

Conostegia plumosa is a rare species and one of the few in the genus to have the abaxial leaf surface tan colored from the dense indument covering it. This characteristic leaf underside is shared with Conostegia dissitinervia , Conostegia centrosperma , Conostegia incurva , Conostegia oligocephala and Conostegia xalapensis . In particular, Conostegia plumosa has been confused with Conostegia oligocephala and Conostegia xalapensis , both of which occur in the same general area of northern Central America. The other species mentioned are endemic to southern Central America. Conostegia plumosa shares the calyptrate calyx and short style with Conostegia xalapensis but not with Conostegia oligocephala which lacks the calyptrate calyx and has an exserted style. Conostegia plumosa can be distinguished from Conostegia xalapensis on the basis of its evident calyptra appendices which are absent in Conostegia xalapensis .

Specimens examined.

MEXICO (fide Schnell). Chiapas: km 33 S of SE on the road to Mal Paso, near Tabasco border, Roe et al. 1371 ( US).

BELIZE. Cayo: Road to Caracol at Guacamallo Bridge, Balick 3104 (NY); along Hummingbird Highway at mile 28.5, Dwyer 11208 (MO, NY); Humming Bird Highway, Gentle 8388 (NY); Mountain Pine Ridge , San Agustin, Lundell 6608, 6770 (NY) . Stann Creek: beyond Middlesex, Gentle 2758 (NY); 17 miles section Stann Creek Valley, Gentle 9258 (NY).

GUATEMALA. Izabal: slopes WNW of (above) El Estor, along margin of open pit nickel mine, Stevens and Martinez 25247 (NY).

HONDURAS. Olancho: Montaña La Bellota 20 kms al N.O. de Campamento, Molina 13436 (NY).

Figures

Figure 185. Distribution of Conostegia plumosa.