Conostegia volcanalis Standl. & Steyermark

Kriebel, Ricardo, 2016, A Monograph of Conostegia (Melastomataceae, Miconieae), PhytoKeys 67, pp. 1-326 : 113-115

Conostegia volcanalis Standl. & Steyermark Fig. 111

Conostegia volcanalis Standl. & Steyermark, Field Mus. Nat. Hist., Bot. sere 23: 136. 1944. Type: Guatemala. Quetzaltenango: Damp forest, Chiquihuite, 1410 m, 8 March 1939, P. Standley 68152 (holotype: F!, isotypes: A!, NY!).

Description.

Trees 2-20 m tall with tetragonal and ridged branches that are generally sparsely to copiously covered with a mixture of caducous, sessile stellate and stalked-stellate hairs; nodal line present. Leaves of a pair equal to somewhat unequal in length. Petioles 0.7-7 cm. Leaf blades 6-32 × 2.6-20 cm, 3-5 plinerved, with the innermost pair of primary veins diverging 1-3.5 cm from the mid vein in opposite to alternate fashion, ovate to elliptic, the base acute or obtuse, the apex acute or obtuse and short acuminate, the margin undulate dentate, the adaxial surface glabrous or glabrescent with sessile or stipitate trichomes which are branching or stellate,the abaxial surface with with sessile or stipitate trichomes which are branching or stellate especially on the veins. Inflorescence a terminal panicle 3.7-16 cm long branching above the base but sometimes appearing branched at the base because of multiple inflorescences arising at opposing meristems at the terminal node, accessory branches present or absent, the rachis glabrescent with few scattered stellate trichomes, bracts and bracteoles to 5 mm long, linear, early deciduous. Pedicel 1.5-15 mm. the hypanthium 2.25-3 × 2.5-3 mm, smooth and mostly glabrous. Flowers 6-10(-12) merous, calyptrate. Floral buds 6-14 × 4-9 mm, spherical, the base rounded or flattened, the apex obtuse to flattened and apiculate, not constricted. Petals 7.5-15 × 4.5-10 mm, white, obovate, spreading, rounded-truncate to emarginate, glabrous. Stamens18-30, 7-8 mm long, radially arranged, to slightly bilateral apparently because of the downward bending style, the filaments 3.75-4.5 mm, white, lacking a geniculation, anthers 2.75-4 × 1-1.25 mm, oblong, straight or recurved, laterally compressed, yellow, the pore 0.1-0.3 mm wide, terminal. Ovary 9-16 locular, inferior, apically glabrous and forming a collar around the style. Style ca. 7 mm long, curving downward, vertical distance from the anthers to the stigma ca. -0.5 - -0.25 mm, horizontal distance ca. 1-2 mm; stigma crateriform, consisting of 9-16 laterally compressed lobes, ca 3-4 mm wide. Berry 10-13 × 8-10 mm, blue-black or purple. Seeds 0.5-0.75 mm, obliquely pyramidal, the testa smooth.

Distribution

(Fig. 112 ). From Mexico through Guatemala to Honduras, 500-2200 m in elevation.

In general, Conostegia volcanalis can be recognized on the basis of its mostly spherical flower buds and broad leaves with undulate dentate margins. Schnell (1996) discussed this species as having "three well defined allopatric races". These morphotypes were considered on the “borderline” of deserving species status ( Schnell 1996). The three morphotypes differed in their distribution, habitat preference, indument density, and floral part size. The first morphotype is found in Guerrero and Jalisco and ( Schnell 1996) noted that as Conostegia jaliscana . These plants prefer streamsides in pine forests. The leaves are is more pubescent and have larger floral parts. These trees flower January through April. The second morphotype recognized by Schnell (1996) occurs in cloud forests of Chiapas, San Marcos and Quetzaltenango in Mexico. The plants from this morphotype are larger trees with less pubescent leaves and flowering November through March. This morphotype is reminiscent of Conostegia icosandra and had been described as Conostegia sphaerica Triana. The third race occurs in cloud forests of central Guatemala, Honduras, El Salvador and Nicaragua. This morphotype Schnell (1996) characterized as being like morphotype one in pubescence but morphotype two in inflorescence structure. The southernmost population within the third morphotype occurs in Costa Rica and Panama and was described as Conostegia orbeliana Almeda. Very few specimens have been collected of this species and they tend to look dif ferent than Conostegia volcanalis because of their few-flowered inflorescences. When it was only known from Panama, Schnell (1996) noted its flowering time as in January, differing from populations from Guatemala to Nicaragua that flower May through October. Very few specimens are known of this species and Costa Rican specimens remeniscent of Conostegia orbeliana have been collected. One of them, was flowering in August, undermining the possible phenological gaps between these populations or possible species. I have chosen not to include Conostegia orbeliana under the synonymy of Conostegia volcanalis not only because they are allopatric, but also because it might also be a variant of for example Conostegia oerstediana or Conostegia macrantha which occur in nearby areas. In general, Conostegia volcanalis is a complex in need of study to assess habitat and phenological specialization. Perhaps more species can be recognized within this complex in the future.

Specimens examined.

MEXICO. Chiapas: southwest side of Cerro Mozotal 11 km northwest of the junction of the road to Motozintla along the road to El Porvenir and Siltepec. Municipio de Motozintla de Mendoza, Breedlove and Almeda 58087 (CAS, NY); on the ridge above Siltepec on the road to Huixtla. Municipio de Siltepec, Breedlove 31999 (CAS, NY); La Trinitaria, east of Laguna Tzikaw , Monte Bello National Park , Breedlove 35147 (CAS, NY); Laguna Salina Montceristo, Matuda 2049 (NY); Mt. Ovando , Matuda 2100, 2644 (MO, NY) . Jalisco: Talpa de Allende, km 12.8 (8 mi) en el camino de La Cuesta hacia Talpa, Cowan and Nieves 4745 (NY); San Sebastian Arroyo de Santa Gertrudis , Mexia 1532 (NY); San Sebastian , Arroyo Monte Oscuro , Mexia 1647 (NY) . Guerrero: San Antonio-Buenos Aires, Montes de Oca, Hinton 14026 (NY); Chilacayote , Mina , Hinton 14188 (NY) . Veracruz: Soteapan, Mapa 21.0/58.5, La Azufrera ca. 18 km al E de Lago Catemaco entre Bastonal y Cerro Campanario, Beaman 6108 (NY); San Andres Tuxtla , Mapa 23.5/55.0, Cerro Vigia al lado E de Volcán San Martín Tuxtla, Beaman and Alvarez 6277 (IE, MO, NY) .

EL SALVADOR (fide Schnell). Santa Ana: Hacienda Montecristo, Metapán, Winkler s.n. (F).

GUATEMALA. Quetzaltenango: Above Mujuliá, between San Martin Chile Verde and Colomba, Standley 85672 (NY); slopes and ridges between Quebrada Chicharro and Montania Chicharro on southeast facing slopes of Volcán Santa María, Steyermark 34333 (NY) . San Marcos: Finca Nueva Granada, Montaña de Vista Hermosa, Kriebel et al. 5565, 5566 (NY, USCG); wet mountain forest near Aldea Fraternidad, between San Rafael Pie de la Cuesta and Palo Gordo west facing slope of the Sierra Madre Mountains , Williams et. al. 25661 (NY) .

HONDURAS. La Paz: Bosque mixto de Cordillera Guajiquiro 5 kms a Sabanetas, Molina and Molina 12906 (NY) . Morazán: Mt. San Juancito, Glassman 1986 (NY); Peña Blanca, Montaña La Tigra, Molina 11056, 14495, 25739 (NY); in cloud forest on Mt. Leyuca , Williams 10013 (NY) .

Figures

Figure 111. Conostegia volcanalis. A Leaf abaxial surface B Inflorescence with flower buds C Longitudinal section of a flower bud D Lateral view of a flower at late anthesis E Petal F Stamen. Photos from specimen vouchered R. Kriebel 5565.

Figure 112. Distribution of Conostegia volcanalis.