Meriania fantastica Alvear, Humberto Mend. & 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 : 26-30

Meriania fantastica Alvear, Humberto Mend. & Almeda , sp. nov. ( Figs. 3 , 4 , 5 )

Meriania fantastica is distinguished by a knobby scutum at the adaxial petiole apex, the strongly revolute auriculate lobes at the abaxial foliar base, the comparatively large flowers about 15 cm in diameter, the orange petals that are blunt-lacerate or irregularly lobed, the dimorphic stamens, and the calyx teeth that are modified into thickened callosities positioned just below the truncate calyx.

Type: — COLOMBIA. Putumayo : Carretera desde San Francisco a Mocoa, alrededores del Km 88, 1° 6.802’ N, 76° 50.060’ W, 2314 m, 16 February 2013 (fl, fr), M. Alvear, J.D. García & D. Alvear. 1851 (holotype: COL!; isotypes: CAS!, CAUP!, CUVC!, FMB!, HUA!, MO!, NY!, PSO!, US!) .

Tree up to 20 m tall. Internodes subquadrangular or quadrangular, with rounded edges, canaliculate. All vegetative and reproductive organs prevailingly glabrous except for the inconspicuous glandular punctuate abaxial foliar surface. Petioles 2.7−7.9 cm long, abaxially flattened; apex with a scutum. Leaves opposite and somewhat anisophyllous, 15.5−31 × 10.4−20 cm, membranaceous, elliptic, elliptic-lanceolate to suborbicular, apex shortly blunt-acuminate and commonly twisted or folded, base truncate to rounded with prominent auricles (0.8–2 × 1.5–3 cm) forming domatial pockets, margin entire to somewhat crenulate; adaxial surface glabrous, abaxial surface minutely glandular-punctate with sessile to short-stalked and sometimes clavate glandular trichomes less than 0.2 mm long; venation acrodromous, the primary nerve flat on the adaxial surface, prominent on the abaxial surface, with 3 pairs of secondary nerves, but only the innermost two pairs 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 with three main branches from the base, with 5−12 pedicellate flowers, rachis with 1−2 nodes, quadrangular; paracladia 7.5 cm long, not branched, branchlets or floriferous shoots triflorous. Bracts and bracetoles not seen. Flowers 5-merous, ca. 15 cm in diameter, on pedicels 1.5−2.5 cm long. Hypanthium 1.4−1.8 cm long, campanulate, glabrous, torus thickened 3.8−5 mm. Calyx truncate, receptacle 0.7−0.9 cm long; external calyx teeth modified into thick roughened callosities. Corolla spreading, petals 6.5−8.5 × 4.0− 5.8 cm, obovate, bright orange, apex strongly asymmetrical, the margin commonly irregularly blunt-lacerate or irregularly ruptured on mature open flowers, glabrous. Stamens 10, slightly dimorphic, the antepetalous whorl with comparatively longer anthers and the antesepalous whorl with comparatively longer filaments; both whorls with magenta filaments, elbow or filament apex/ base of the connective junction yellow, anthers purple-magenta; dorsal connective appendages absent. Antepetalous stamens: filaments 3.3−3.5 cm long, ascendant elbow or filament apex/base of the connective junction triangular and expanded on the sides, ca. 1.0 cm long; anther thecae 2.2−2.5 cm long, subulate and slightly sigmoid, pore 0.73−0.85 mm in diameter, dorsally inclined; pedoconnective absent. Antesepalous stamens: filaments 3.5−4 cm long, ascendant elbow or filament apex/base of the connective junction triangular, 0.79−0.97 cm long; anther thecae 1.4−1.8 cm long, subulate and sigmoid, pore 0.78−0.85 mm in diameter, dorsally inclined; pedoconnective absent. Style 1−2.3 cm long, conic, apically curved in open flowers, magenta; stigma slightly expanded. Ovary 1.0−1.3 × 0.89−9.3 cm, ovoid, apically lobed, superior, 5-locular, apex with rounded lobes 0.2−1.3 mm long enclosing the style base; axile placentae obovate with cordate apex 2.2−2.5 × 2.2−2.4 mm, with ovules concealing the entire surface. Capsule 1.8−2 × 2−2.3 cm, only partially to medially enclosed by the hypanthium and remains of the receptacle. Seeds 1.5−2.2 mm long, cuneiform, pale brown, lateral symmetrical plane oblong-cuneate, the chalazal end expanded into an inconspicuous apically truncate appendage, the antiraphal plane bluntly angled, the raphal zone oblong, dark brown and extending about ¼ the length of the seed, testa ± smooth.

Phenology: ―The species has been collected with flowers in February, March and September, and with fruits in March.

Habitat and distribution: ― Endemic to Colombia where it is only known from six collections, five from Putumayo (road from Valle del Sibundoy to Mocoa ) and one from Cauca ( Santa Rosa , Bota Caucana ). All the collections come from a small region on the eastern flank of the “Nudo de los Pastos” and “Macizo Colombiano”, an area where the three Colombian cordilleras of the Andes are united in southernmost Colombia. This eastern flank drains to the Amazon basin. This species grows in Andean forests at 1500 and 2000−2800 m .

Etymology: —The name of this new species refers to the unusually large and strikingly showy flowers.

Conservation status: ―This species is known only from two populations. Most of the collections come from the population in Putumayo from the forests along a main road in an region lacking protected status. The other collection comes from the buffer zone of the Serranía de los Churumbelos National Park. 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 extent of occurrence for Meriania fantastica is 144.536 km ² and the area of occupancy is 12.000 km ². Using IUCN guidelines and criteria ( IUCN 2001, 2011, 2014) and its restricted extent of occurrence, we assign this species a conservation status of Endangered EN B2ab(iii). It is important that urgent measures be taken to protect the few known sites where this species grows. We also strongly advise propagation in botanical gardens since this species has extraordinary ornamental potential.

Additional specimens examined (paratypes): ― COLOMBIA. Cauca: Santa Rosa, corregimiento de San Juan de Villalobos, vereda Palmeras , zona amortiguadora del Parque Nacional Serranía de Los Churumbelos , camino a la quebrada La Puerca y al Filo del Tigre , 1° 30.179’ N, 76° 20.228’ W, 1523 m, 21 February 2013 (fl) M . Alvear et al. 1911 ( CAS!, COL!) ; Putumayo: Mocoa, Río Blanco , 2400 m, 28 February 1981 (fl), G . Mahecha 8869 ( COL!); carretera San Francisco−Mocoa , 2100−2300 m, 30 January 1973 (fl), L. E . Mora-O. 6242 ( COL!); San Francisco−Mocoa , 2000 m, March 1978 (fl), F . Sánchez s.n. ( COL!); Río Blanco , 2400 m, March 1981 (fl), G . Mahecha s.n. ( COL!); Mocoa , carretera entre Sibundoy y Mocoa , El Mirador , 2000 m, 7 September 1998 (fl), H . Mendoza 6056, 7019 ( FMB!); Sibundoy , entre Río Blanco y La Cabaña, 2300−2800 m, 6 March 1987 (fl), B . Ramírez 937 ( PSO!); Mocoa , carretera entre San Francisco y Mocoa, 2700 m, 29 January 1973 (fl), E . Hernández 351 ( PSO!) .

from Alvear 1851; Meriania hernandoi photos from Alvear 1856; all photos by M. Alvear).

Figures

FIGURE 3. Meriania fantastica. A. Flowering branch. B. Leaf base detail (abaxial surface), indument detail at 60X. C. Leaf base detail (adaxial surface). D. Flower. E. Flower bud. F. Ovary cross section in bud, showing placentation. G. Ovary and style. H. Stamens in lateral view, antesepalous (right) and antepetalous (left). I. Post-mature capsule. J. Seed in lateral view. (A–J from Alvear 1851, CAS, COL).

FIGURE 4. Meriania fantastica. A. Flowering branch (flower in lateral view). B. Flowering branch with flower buds. C. Flower. D. Two antesepalous stamens (left) and two antepetalous stamens (right). E–F. Leaf base details (abaxial surfaces). (All photos from Alvear 1851 by M. Alvear).

FIGURE 5. Meriania fantastica and M. hernandoi comparison. A. Flower comparison, M. fantastica (left), M. hernandoi (right). B. Flower comparison, showing abaxial petal surfaces and hypanthia, M. fantastica (left), M. hernandoi (right). C. Leaf (abaxial side) of M. fantastica. D. Leaf (abaxial side) of M. hernandoi. E. Branch with node and leaf bases of M. fantastica. F. Branch with node and leaf bases of M. hernandoi. G. Leaf base (adaxial side) of M. fantastica. H. Leaf base (adaxial side) of M. hernandoi (Meriania fantastica photos