Meriania barbosae Humberto Mend., Alvear & Almeda, 2014

Mendoza-Cifuentes, Humberto, Almeda, Frank & Alvear, Marcela, 2014, Novelties in Meriania (Melastomataceae: Merianieae) from Andean rainforests of Colombia, Phytotaxa 178 (1), pp. 23-32 : 24-25

Meriania barbosae Humberto Mend., Alvear & Almeda , sp. nov. ( Figs. 1 , 2 )

Meriania barbosae is distinguished by its rufous pubescence on the branches, petioles, inflorescence, hypanthium and calyx; sessile glandular hyaline trichomes on the abaxial foliar surface; foliar lamina base subpeltate; calyptrate calyx, calyptra obtuse apically with dorsal or external teeth like rough calluses; corolla spreading; stamens slightly dimorphic, with subulate dorsal connective appendages.

Type:― COLOMBIA. Caldas: Florencia, de Ranchoquemado por la vía a Pensilvania, Parque Nacional Natural Selva de Florencia , 5º23’13”N, 75º9’48” W, 1800−2000 m, 27 September 1993 (fl), C . Barbosa 14932-95 (holotype: FMB! 34472; isotypes: COL!, HUA) .

Tree up to 6 m tall. Young branches quadrangular. Branches, petioles, inflorescence branches, hypanthium and calyx densely covered with a rufous indumentum of asperous-headed to irregularly branched trichomes 0.3−1.2 mm long, also with hyaline sessile glandular trichomes ca. 0.1 mm in diameter. Petioles 2−5.2 cm long, terete. Leaves opposite and isophyllous, 16.5−20.5 × 9−11 cm, ovate to elliptic, apex blunt-acuminate, base subpeltate, or rounded to slightly cordate when young, margin entire; adaxial surface glabrous, abaxial surface with hyaline sessile glandular trichomes and branched trichomes similar to those on the branches, mostly restricted to the veins; venation acrodromous, the primary nerve flat on the adaxial surface, prominent on the abaxial surface, with 2−3 pairs of secondary nerves, but only the innermost pair extending to the blade apex and converging with the primary nerve, the secondaries basal, impressed on the adaxial surface and prominent on the abaxial surface, tertiaries percurrent (transversals), impressed on the adaxial surface, slightly prominent on the abaxial surface. Inflorescence terminal, compound thyrsoid, 10−12 cm long, sessile or pedunculate, penduncle 3−3.5 cm long, with 6−15 pedicellate flowers, rachis with 2−3 nodes, quadrangular; paracladia 6−8 cm long, not branched, branchlets triflorous with scars of aborted flowers at the base of the adjacent persistent flowers. Bracts and bracetoles not seen. Flowers 5-merous, on pedicels 7−11 mm long. Hypanthium 9−10 mm long, cup-like, cylindrical, externally smooth, torus thickened 4−4.5 mm. Calyx calyptrate, calyptra apically obtuse in bud, opening by irregular fissures with basal parts of the calyx remaining attached to the hypanthium in post-dehiscence, in fruit lengthening up to 5 mm long; external or dorsal teeth roughened-callous. Petals 2.9−3.2 × 2.2−2.4 cm, magenta, spreading, obovate, glabrous. Stamens 10, slightly dimorphic, the antepetalous whorl with longer anthers. Antepetalous stamens: filaments 1.6−1.8 cm long, ascendant elbow or filament apex/base of the connective junction triangular, ca. 5.5 × 2 mm; the dorsal connective appendage ca. 5 mm long, subulate, parallel to the anther and pointing to the apical pore; anther thecae ca. 12 mm long, subulate and sigmoid, pore 0.3−0.4 mm in diameter, dorsally inclined; pedoconnective ca. 1−2.6 mm long. Antesepalous stamens: filaments 1.7−1.8 mm long, ascendant elbow or filament apex/base of the connective junction widely triangular, ca. 3−3.2 × 2.5−2.6 mm; dorsal connective appendage ca. 3.5 mm long, subulate, parallel to the anther and pointing to the apical pore; anther thecae ca. 10 mm long, subulate and strongly arched dorsally, pore 0.3−0.4 mm in diameter, dorsally inclined; pedoconnective absent. Style 1.8 cm long, cylindrical, apically curved in open flowers; stigma slightly expanded. Ovary 6−7 × 6 mm, ovoid, superior, 5-locular, fused to hypanthium basally up to 1 mm, apex with a few tooth-like lobes that do not enclose the style base; axile placentae 2.3 × 1.2 mm, obovate, with ovules concealing the surface. Immature capsule 1.3−1.7 × 1.3−1.4 cm, completely enclosed by the hypanthium and remnants of the receptacle. Immature seeds 2.5−2.8 mm long, narrowly cuneiform, brown, lateral symmetrical plane narrowly oblong, the chalazal end expanded into an elongate wing-like apically ± horizontally flattened appendage, the antiraphal plane rounded-angulate, the raphal zone narrowly oblong-carinate, extending the entire length of the seed and expanded at the hilar end into an acicular appendage, testa ± smooth.

Phenology: —Collected in late September with flowers, and with fruits in March.

Habitat and distribution: ― Endemic to Colombia where it is known only from the type locality in the Selva de Florencia National Park , located in the department of Caldas on the eastern flank of the cordillera Central. This species grows between 1573 and 2000 m .

Conservation status: ―This species is presently known only in the Selva de Florencia National Park. This protected area was established in 2005 with an area of ca. 100 km 2 of subandean forest at 850−2400 m, with high levels of precipitation (over 8000 mm annually). It is surrounded by highly disturbed areas and more than 50 peasant families still reside within the park boundaries ( Parques Nacionales Naturales de Colombia 2014). Based on georeferenced data from the known collections, GeoCAT ( Bachman et al. 2011) was used to calculate extent of occurrence (EOO) and area of occupancy (AOO) based on a user defined cell of 2 km. The area of occupancy for Meriania barbosae is 8.000 km ². Using IUCN guidelines and criteria ( IUCN 2001, 2011, 2014), we assign this species a conservation status of Critically Endangered CR B2ab(iii). It will be important to encourage ex situ propagation in botanical gardens in Colombia and elsewhere.

Etymology: ―We dedicate this new species to César Barbosa , a notable Colombian botanist, and collector of the type specimen. His botanical collections from Selva de Florencia National Park represent the first ever made in this protected area.

Additional specimens examined (paratypes): ― COLOMBIA. Caldas: Samaná, corregimiento de Florencia, Parque Nacional Natural Selva de Florencia, sector de manejo Florencia , sendero Bocatomas , cerca de Río Claro , 05°31.34’ N, 75°3.678’W, 1573 m, 2 March 2011 (fr), M. Alvear et al. 1459 ( CAS!, COL!, FMB!, HUA!, NY!) .

Figures

FIGURE 1. Meriania barbosae. A. Flower bud. B. Flower bud in longitudinal section. C. Detail of ovary (longitudinal section) and style. D. Petal. E. Detail of ovary apex. F. Flowering branch. G. Antepetalous stamen in lateral view. H. Elbow of the antepetalous stamen in dorsal view. I. Antesepalous stamen in lateral view. J. Elbow of the antesepalous stamen in dorsal view. (A–J from Barbosa 14932-95, FMB). Line drawing by H. Mendoza-Cifuentes.

FIGURE 2. Meriania barbosae. A. Branch with infructescence. B. Immature fruits. C. Immature fruit in longitudinal section. D. Leaf (abaxial surface) showing venation and indument (all photos from Alvear 1459 by M. Alvear).