Conostegia allenii (Almeda) Kriebel, 2016

Kriebel, Ricardo, 2016, A Monograph of Conostegia (Melastomataceae, Miconieae), PhytoKeys 67, pp. 1-326 : 146-147

Conostegia allenii (Almeda) Kriebel comb. nov. Fig. 135

Conostegia allenii (Almeda) Kriebel. Basionym: Clidemia allenii Almeda, Proc. Calif. Acad. Sci. Series 4, 55(4): 90, f. 1. 2004. Type: Costa Rica. Puntarenas: Cantón de Osa, Golfo Dulce Area in the vicinity of Esquinas Experiment Station at sea level, 16 April 1949, P. H. Allen 5265 (holotype: CAS!, isotypes: AAU, CR, INB!, MEXU, MO, US!).

Description.

Shrub to small trees 1.5-5 m tall with terete to flattened internodes that are moderately to copiously covered with smooth spreading hairs 1.5-3 mm long, sometimes underlain with a sparse to moderate understory of sessile stellate and stipitate-stellate hairs; the nodal line not evident. Leaves at a node equal to somewhat unequal in length. Petiole absent or up to 1.2 cm long. Leaf blades 3.5-23 × 1.8-10 cm, 5-7 plinerved with the innermost pair of primary veins diverging from the midvein 0.7-1.5 cm above the base and arising in alternate fashion, elliptic to elliptic-ovate, oblique and rounded, acuminate to attenuate, entire and ciliate varying to obscurely denticulate distally, adaxially moderately covered with spreading hairs 1-2.5 mm long to nearly glabrous, abaxially moderately to sparingly covered with spreading simple hairs 1-3 mm long on the median vein and innermost primaries and sparsely underlain with sessile stellate and stipitate-stellate hairs varying to glabrate. Inflorescence a pseudolateral modified dichasium 2.6-9 cm long sometimes divaricately branched from the base, accessory branches absent, the branches reddish green to red, moderately to copiously covered with smooth spreading hairs, sometimes underlain with a sparse to moderate understory of sessile stellate and stipitate-stellate hairs, bracteoles 1-6 mm long, subulate to narrowly triangular, persistent. Pedicel 0.5-1 mm long. Flowers 5 merous, calyx not calyptrate. Floral buds 3.75-4.25 × 3-3.5 mm, cupulate to campanulate, the hypanthium 3-4 × 2.5-3.5 mm, moderately to sparingly covered with spreading hairs 1-3 mm long and sparsely underlain with deciduous sessile stellate and stipitate-stellate hairs; calyx tube 0.5 mm long, calyx lobes hyaline, rounded-triangular, 0.25-1.5 mm long, calyx teeth linear to subulate, 2-4 mm long. Petals 4.5-5 × 1-2 mm, white or reportedly pink, oblong to oblong-ovate, reflexed, glabrous, truncate or rounded. Stamens 10, radially arranged around the style, the filament 2-2.5 mm long with a geniculation near the apex, yellow, anthers 1.5-2 × 0.5 mm, linear-oblong, yellow, the pore ca. 0.1 mm, terminal and slightly ventrally inclined. Ovary 5-locular, 2/3 inferior, apex elevated into a low ringlike collar with or without smooth hairs that surround the stylar scar. Style ca. 7 mm long, straight to slightly curving, vertical distance from the anther apex to the stigma ca. 1.5-2.5 mm, horizontal distance absent, stigma punctiform, ca. 0.25 wide. Berry 5 × 5 mm, purple black. Seeds ca. 0.5 mm long, more or less triangular in profile, angulate and somewhat muriculate to papillate on the convex face.

Distribution

(Fig. 136 ). Primary forest understory in the Golfo Dulce and Osa Peninsula region in southern Costa Rica, and a population in Panama on the Santa Rita Ridge, from sea level to 400 m elevation.

Conostegia allenii can be distinguished by its sessile to subsessile leaves that usually have oblique bases, pseudolateral inflorescences, and reddish hirsute indument on inflorescence branches and hypanthium. In the protologue Almeda (2004) mentioned the specimen Quesada 591 (INB) from Rincón de Osa as somewhat unusual in hav ing glabrous adaxial foliar surfaces. An additional specimen from this locality (Aguilar 13243 - NY) also has glabrous leaves adaxially. The latter specimen was accompanied by photographs of the flowering plant (Fig. 135 ) which evidenced the white petals of the flowers. Other Costa Rican specimens reportedly have pink flowers, and the only other report of white petals in this species are the only known Panamanian specimen cited above. Conostegia allenii represents a strong case of vegetative convergence with taxa such as Clidemia costaricensis and Clidemia petiolaris . Almeda (2004) compared Conostegia allenii to both of these taxa in the protologue because of their similar indument and inflorescence.

Specimens examined.

COSTA RICA. Puntarenas: Rancho Quemado, camino a Drake, parte mas elevada del camino, Aguilar 13243 (NY); Sendero por el acueducto de Sierpe, Gonzalez 3586 (INB); Bosque primario a la par de la carretera Interamericana 3 km N de Chacarita, Nepokroeff and Hammel 722 (CAS, CR); Cantón de Osa, Rancho Quemado, Rincón, Quesada 591 (INB, MO).

PANAMA. Colón: Santa Rita ridge, km 21.2, de Nevers 7207 (CAS).

Figures

Figure 135. Conostegia allenii. A Leaf abaxial surface B Leaf base abaxial surface and infructescence C Leaf adaxial surface and infructescence D Close up of the flower. Photographs taken by Reinaldo Aguilar and vouchered R. Aguilar 13243.

Figure 136. Distribution of Conostegia allenii.