Conostegia trichosantha (Almeda) Kriebel, 2016

Kriebel, Ricardo, 2016, A Monograph of Conostegia (Melastomataceae, Miconieae), PhytoKeys 67, pp. 1-326 : 228-231

Conostegia trichosantha (Almeda) Kriebel comb. nov. Fig. 198

Conostegia trichosantha (Almeda) Kriebel. Basionym: Clidemia trichosantha Almeda, Proc. Calif. Acad. Sci, Series 4, 43(17): 274, f. 2. 1984. Type: Panama. Coclé: sawmill above El Cope, in forest along stream E of sawmill on the Atlantic drainage, elev. 2300 ft (701 m), 27 July 1978, B. Hammel 4133 (holotype: CAS!, isotype: MO).

Description.

Shrub 1-2.5 m tall with terete stems that are moderately to densely covered with smooth e spreading hairs mostly 1-3 mm long; the nodal line inconspicuous and not evident from the indumenta. Leaves of a pair equal or usually unequal in size. Petiole 0.1-2.2 cm. Large leaf blade 5-14.5 × 2.5-6 cm, 5-7 plinerved with the innermost pair of primary veins diverging 0.6-2.2 cm above the blade base and in alternate fashion, elliptic, acute to obtuse, rounded or oblique, acuminate, the margin conspicuously serrate denticulate, adaxially moderately to sparely strigose to hirtellous, abaxially hirsute. Inflorescence a pseudolateral, modified and usually deflexed dichasium with flowers borne in pedunculate terminal glomerules 1.2-3 cm, branched above the base, accessory branches absent, the rachis densely hirsute, lanceolate to naviculiform, 1.5-3 × 0.5-1.5 mm. Flower buds 1.75-2.5 × 1.25-1.75 mm, more or less ovoid, copiously covered with smooth spreading trichomes. Flowers 5 merous, not calyptrate, the hypanthium 1.75-2.2 × 1.5 mm wide, calyx lobes broadly deltoid, 1 × 1.5 mm long, calyx teeth setiform, 1-2 mm long. Petals 4-4.5 × 1.5-2 mm, translucent white, elliptic-lanceolate, spreading to somewhat reflexed, apex acute, glabrous. Stamens 10, radially arranged around the style, the filaments 2-2.5 mm, with a geniculation near the apex, translucent white, anthers 1.25-1.75 × 0.5-0.75 mm, linear-oblong, yellow, somewhat laterally compressed, the pore ca. 0.15 mm wide, truncate. Ovary 5-locular, 2/3 inferior, apically mostly glabrous but with some scattered sessile glands and elevated into a low lobulate collar around the style. Style 5-6.5 mm, gently curving, vertical distance from the anther apex to the stigma 2-2.5 mm, horizontal distance ca. 0.5 mm, stigma punctiform and conspicuously papillose, 0.3-0.4 mm wide. Berry 4-6 × 4-5.5 mm, dark purple; seeds 0.3-0.5 mm, cuneate to triangular, smooth with verruculose angles.

Distribution

(Fig. 199 ). Endemic to Panama where it grows mostly in cloud forests, 250-1250 m in elevation.

Conostegia trichosantha is a very distinctive species because of its dense indument of smooth hairs, small leaves with very plinerved and usually asymmetric venation, pseudolateral, short inflorescences, 5-merous flowers with narrow and acute white petals and very exserted styles. It is perhaps not surprising that in the molecular phylogeny, Conostegia trichosantha appears as closely related to other Panamanian endemics such as Conostegia jefensis and Conostegia peltata as well as with the more widespread Conostegia consimilis . With these taxa it shares narrow petals and with most of them angulate seeds with verruculose angles. This species accumulates water in the hypanthium indument.

Specimens examined.

PANAMA. Coclé: about 7-10.5 km beyond El Cope in Omar Torrijos National Park, along end of the rocky trail to Río Blanco and Limon beyond Alto Calvario, Almeda et al. 7653 (CAS); 7 kms north of El Cope , area around Rivera Sawmill, called Alto Calvario, New Works, Folsom et al. 7093 (CAS) . Panamá: forested slopes along El Llano Cartí road 12 km from Panamerican Highway, D’Arcy 10617 (CAS); loc. cit., Sytsma and Anderson 4493 (CAS); Comarca de San Blas , Nusagandi, along Continental Divide on the El Llano Carti Road, de Nevers and Pérez 3577 (CAS); Nacional Chagres, Cerro Jefe, Road leading NE from TV towers, Penneys and Blanco 1697 (FLAS, NY) . Veraguas: along trail to summit of Cerro Tute above the Escuela Agricola Alto de Piedra near Santa Fé, Almeda et al. 6491 (CAS); P. N. Santa Fé, sendero a la cima del Cerro Mariposa, Kriebel and Burke 5693 (PMA, NY) .

Figures

Figure 198. Conostegia trichosantha. A Habit B Leaf abaxial surface C Inflorescence D Close up the flower E Floral bud F Longitudinal section of a flower bud with the style removed G Pickled flower H Longitudinal section of a flower at anthesis with the style removed I Petal J Stamen K Style. Photos of specimen vouchered R. Kriebel 5693.

Figure 199. Distribution of Conostegia trichosantha.