Miconia pozuzoana L. Cárdenas & Michelang., 2014

Cárdenas, Lizeth A., Burke, Janelle M. & Michelangeli, Fabián A., 2014, Five new species of Miconia (Melastomataceae) from the Central Peruvian Andes, Phytotaxa 188 (3), pp. 121-134 : 126-128

Miconia pozuzoana L. Cárdenas & Michelang. sp. nov. ( Fig. 3 )

Treelet with stems acutely angled and sulcate; peduncles quadrangular, fleshy and clearly winged, bracts foliaceous; flowers pedicellate, petals 5–6, pleiostemonous; filaments with a few pedicellate glands; ovary 6-locular, style bending away from the anthers, glabrous; stigma capitate.

Type:— PERU. Pasco: Oxapampa, Pozuzo , Sector Huampal , Pan de Azúcar , cerca al área de observación de gallitos de las rocas. 10°11ʹ05ʺS, 75°34ʹ51ʺW, 1000–1100 m, 22 July 2006 (fl), L. Cárdenas & V. Flores 622 (holotype HOXA!, isotypes AMAZ!, CUZ!, HUT!, MOL!, MO!, NY!, USM!) .

Treelet, up to 2–3.5 m. Young stems acutely angled and sulcate, glabrous, internodes longitudinal ridges absent, nodal line raised and slightly darker than the stem, some internodes hollow and with orifices (presumably for ants). Leaves slightly anisophyllous; petiole 3–4.2 cm long, glabrous; blade 16–24 × 7.5–10 cm, elliptic, coriaceous, base acute to obtuse, apex narrowly acute, occasionally cuneate, margin entire to obscurely undulate; secondary veins 1 pair plus 1 pair of faint marginals, shortly plinerved [diverging <0.8 cm above the base, symmetrical or slightly asymmetrical (even on the same branch)], tertiary veins percurrent, the quaternaries reticulate, areoles 1.8–5 mm wide, all veins flat on the adaxial surface, of the abaxial surface the primary and secondaries raised, tertiaries and quaternaries flat; adaxial surface glabrous; abaxial surface glabrous, the primary veins with a mix of sparse small simple and stellate trichomes <0.1 mm long; smaller leaves up to 35% reduced with the smaller leaf alternating sides on the branch. Inflorescences terminal panicle, 14–20 cm long; peduncles quadrangular, fleshy and clearly winged, pale green and reddish (in vivo), with a mix of very sparse dendritic trichomes and amorphous scales <0.1 mm wide; bracts 4.5–7 × 2–3.5 cm, foliaceous, obovate, caducous; bracteoles 6–7 × 1.5–1.7 cm, gladiate, persistent at least until anthesis, most caducous afterwards. Flowers with the pedicel 4.5–7 mm long, tetragonal and clearly winged. Hypanthia 2.8–3.1 mm long, cylindrical to narrowly tubular, 2 mm wide at the torus, glabrous to very sparsely sessile-glandular, internal surface with 5–6 faint ridges, glabrous. Calyx open in bud, tube 1–1.3 mm long at anthesis, lobes 1.2–1.4 × ca. 2.4 mm, deltoid, pubescence as in the hypanthium, pale green yellowish; calyx teeth subulate, ca. 3.4 × ca. 1 mm, pale green. Petals 5–6, 6.5–7 × 4.2–5 mm, broadly obovate to suborbicular, spreading, bright white at anthesis (drying brown), glabrous, the apex emarginate, the base truncate, the margin entire. Stamens pleiostemonous, with up to 18 stamens, isomorphic or nearly so, around the style at anthesis; filaments 5–5.5 mm long, bright yellow becoming reddish in older flowers, with a few pedicellate glands; anthers with 4 locules, thecae 2.4–2.8 × ca. 0.7 mm, narrowly oblong, opening by 1 apical to dorsally-oriented broad pore, yellow at anthesis, later turning orange or reddish, connective extending up to 0.3 mm below the thecae, with two obscure basal and ventral appendages <0.1 m long, pale yellow. Ovary 6-locular, 1/4 to fully inferior, the free portion projecting ca. 0.5 × ca. 1 mm, truncate-conical, glabrous, ribbed at the apex, with a corona of small setae; style 7.5–8 mm long, bending away from the anthers, pale white to pale pink, glabrous; stigma capitate, ca. 1.7 mm wide. Berries not seen.

Habitat and Distribution:— Miconia pozuzoana is endemic to cloud forests at 1000–1100 m in central Peru where it has been collected four times.

Phenology:—Flowering material of Miconia pozuzoana has been collected in July.

Etymology:—This new species is named after the district where it grows in the forests of central Peru.

Conservation Status:— Miconia pozuzoana is only known only from three populations inside the Yanachaga Chemillen National Park, with an extent of occupancy (EOO) of less than 20 km 2. Based on its restricted distribution and habitat, following IUCN criteria (2001) as implemented in the IUCN guidelines (2011) we recommend that this species is considered Endangered.

Additional specimens examined (paratypes):— PERU. Pasco: Oxapampa, Pozuzo, sector Yulitunqui , 10˚16’44’’ S , 75˚31’37” W, 1700 m (fl, fr) 18 Nov 2008, J. R . Ayerbe & D. Heredia 204 ( MO, HOXA, USM!); Oxapampa, Pozuzo, Sector Huampal, cercano al puesto de control y la parcela controlada, 10˚11’14” S, 75˚34’49” W , 16 Jul 2008 (fl), L . Cárdenas & V . Flores 523 ( AMAZ!, CUZ!, HOXA!, HUT!, MO!, MOL!, USM!); Parque Nacional Yanachaga Chemillén, Carretera Chontabamba al puesto de vigilancia Huampal , 10˚11’ S , 75˚34’ W, 1150 m , 19 Sep 2002 (fr), A . Monteagudo, C . Mateo, G . Ortiz 3890 ( MO, USM!) .

Discussion:— Miconia pozuzoana is morphologically similar to a group of species found at mid-elevation forests throughout the Andes with hollow stems, relatively large flowers (hypanthia of at least 3.5 mm), obovate anthers that open by a minute pore (in some species the apex of the anther is tapering), capitate stigma, and glabrous to glabrescent leaves: M. bailloniana Macbride (1941: 388) , M. expansa Gleason (1936: 536) , M. huanucensis Wurdack (1972: 201) , M. flacida Gleason (1931: 226) , and M. hospitalis Wurdack (1972: 475) . Based on anther morphology the first three species have been assigned to Miconia section Amblyarrhena and the latter two to Miconia section Tamonea (Aublet 1775: 441) Cogniaux (1886: 238) , but because most sections of Miconia are not monophyletic, it is likely that all of these species are closely related based on the character combination mentioned above. Miconia pozuzoana can be easily distinguished by the inflorescences with at least some persistent bracteoles (vs. caducous in all the above species), and the combination of six-merous and pleiostemonous flowers. Among the species mentioned above, only M. huanucensis has some six-merous flowers (although they are mostly five-merous) and M. flaccida may be diplostemonous or pleiostemonous. The winged inflorescences of M. pozuzoana are similar to those of M. flaccida and M. bailloniana . However, hypanthia and fruit are also winged in M. bailloniana and some branches of M. flaccida , while they are always terete in M. pozuzoana .

Additionally, M. pozuzoana may also be related to Conostegia inusitata Wurdack (1968: 170) and a closely related undescribed species (see Schnell 1996). Conostegia inusitata has been placed in Conostegia due to the presence of flowers with calyptrate calyx and numerous stamens ( Wurdack 1968), however calyx morphology and anther shape differs from that of Conostegia sensu stricto, which led to Schnell (1996) to propose a new genus to accommodate these two species, Florbella, which is not yet validly published. Recent detailed analyses of seed and flower morphology, as well as molecular data show that Conostegia inusitata is not closely related to the other members of Conostegia , and rather it is placed within a large group of Andean Miconia with large flowers (R. Kriebel pers. comm.) and these two species also have quadrangular hollow stems ( Michelangeli 2010).

Figures

FIGURE 3. Miconia pozuzoana. A. Flowering branch. B. Inflorescence detail. C. Cross section of mature fruit. D. Anthers on side view. E. Detail of the apex of the filament. F. Anther in cross section. G. Flower in longitudinal section. H. Flower. I. Petal, adaxial surface (Cardenas 622, NY).