Tococa stephanotricha Naudin

  • Family

    Melastomataceae (Magnoliophyta)

  • Scientific Name

    Tococa stephanotricha Naudin

  • Primary Citation

    Ann. Sci. Nat., Bot. ser. 3, 16(2): 95. 1850

  • Type Specimens

    Specimen 1: Isotype -- E. F. Poeppig 1844, verif. F. A. Michelangeli, 2000

  • Description

    Description Author and Date: Fabian A. Michelangeli, January 2010, based on Michelangeli, F. A. (2005). Tococa (Melastomataceae). Flora Neotropica Monographs 98: 1-114.

    Type: Brazil. Amazonas: in Brasilia septentrionali, secus flumen Amazonum, loco dicto Maynas Alto. Poeppig 1844 (holotype P; isotypes BR, NY).

    Description: Shrub, to 1.0-3.0 (-4.5) m tall. Stems densely glandular setose, the trichomes 3-4 mm long, persistent, the nodes glabrous. Petioles (1.0-) 1.5-3.5 cm long, with glandular and non- glandular setae. Leaves slightly anisophyllous, one leaf 20-25% smaller than the one opposite to it, oblong to ovate, the larger leaves 11-25 x 6-9 (-12) cm, apex acute to long acuminate, base round to obtuse, adaxial surface adpressed-setose, abaxial surface sparsely glandular pubescent, densely hirsute to glandular setose on the primary and secondary veins, light green, with 2 pairs of secondary veins, basally nervate, membranaceous, entire to serrulate, slightly ciliolate; domatia free from the leaf blade, usually present in both leaves of each pair, globose to ovoid, 0.8-1.5 (-2.5) x 0.5-1.2 (-1.7) cm. Inflorescence an axillary, occasionally terminal, panicle of 5-15 flowers, 3-7 (-10) cm long, the axis green, terete, densely glandular setose, the trichomes with a crimson to brown tinge. Flowers on pedicels thin (less than 0.5 mm wide), 8-11 mm long, flared at the apex, bracts absent; hypanthium conical, 7-8 mm long, with 8-10 wings (0.2-0.5 mm wide), that run from the base of the hypanthium up to the torus, projecting 0.5-1.5 mm from the hypanthium surface, the larger set opposite the sepals, the smaller one alternate the sepals, the wings densely glandular setose, glabrous in between; sepals obscurely lobed, membranaceous, 7-9 mm long, calyx teeth projecting upwards as subulate teeth, and slightly laterally compressed; the ring inside the torus glabrous. Petals 4-5, 10-13 x 5-6 mm, base oblong to slightly attenuate, emarginated at the apex, the margins retuse, smooth, glabrous, red to dark pink, turning white after anthesis. Stamens all of the same size, the filaments 5-6 mm long, glabrous; anthers yellow; the connective with a dorsal-basal blunt tooth; thecae 4.5-5.5 mm long, opening by a ventrally inclined pore. Ovary 3,5-locular, 1/2-2/3 inferior, the superior portion conical, the apex with a corona of short (1.5 mm long) setae; style glabrous, 13-14 mm long, purple to fuchsia; stigma peltate, 3 mm wide. Fruits globose, 7-9 mm long, black, glabrous between the hypanthium wings, glandular setose on the wings. The seeds evident through the pericarp, truncate-obovate to triangular, 0.6-1.5 mm long, without capitate trichomes in the raphal area, without sculpturing, anticlinal walls straight, periclinal walls convex, boundaries between periclinal walls flat. Chromosome number n= unknown.

    Habitat and Distribution: Growing in the understory of montane tropical forests in NE Peru, adjacent SE Colombia and NW Brazil, from 200 to 1100 m.

    Taxonomy and Systematics: Tococa stephanotricha is closely related to T. stenoptera, from which it can be easily distinguished by inflorescence morphology and stem pubescence. Variation across populations in the size of the outer and inner calyx and the petals makes the differentiation of T. temnoptera from T. stephanotricha difficult, therefore both taxa are here considered to be synonyms. The original description cites the ovary as 5-locular, but dissections of considerable amount of specimens have shown that this character is variable even within flowers of the same individual. Most flowers dissected had 3-loculed ovaries, although some had 5, and very rarely 4. Also, there is variation in the merosity, with about half of the specimens bearing 5-merous flowers and the other half bearing 4-merous flowers. In addition to the characters of the calyx, traditionally used to distinguish these species (see key), T. stephanotricha tends to have larger paniculate inflorescences, while T. quadrialata or T. gonoptera have cymose or subumbellate inflorescences. However, there is considerable variation in the size and shape of the calyx wings across these taxa, making the differentiation between T. stephanotricha and T. quadrialata or T. gonoptera extremely difficult for some specimens. The amount of variation in calyx morphology is such that the recognition of these three species may not be warranted. However, until more material is studied, particularly of T. gonoptera, they will be considered as distinct species. In general, specimens with the character combination associated with T. stephanotricha tend to be found at higher elevations than those traditionally determined as T. quadrialata or T. gonoptera. Also, see note under T. stellata in excluded and doubtful taxa.

  • Floras and Monographs

    Tococa stephanotricha Naudin: [Article] Michelangeli, Fabián A. 2005. (Melastomataceae). Fl. Neotrop. Monogr. 98: 1-114.