Tococa aristata Benth.

  • Family

    Melastomataceae (Magnoliophyta)

  • Scientific Name

    Tococa aristata Benth.

  • Primary Citation

    J. Bot. (Hooker) 2: 305. 1840

  • Type Specimens

    Specimen 1: Isotype -- R. H. Schomburgk s.n., 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: Guayana (British Guiana): sides of sreeks, Schomburgk 458 (holotype K; isotypes NY, P).

    Description: Shrub, to 1.0-2.5 m tall. Stems glandular setose, the trichomes 1.5-3.5 mm long, persistent, the nodes glabrous. Petioles 1.5-3.5 cm long, glandular setose. Leaves isophyllous, elliptic, (5-)10-25 (-30) x (3-) 5-15 cm, apex abruptly acuminate to shortly caudate or aristate, base acute to broadly acute, adaxial surface glandular setose, abaxial surface sparsely glandular setose, hirsute on the primary and secondary nerves, usually light green, purple or dark red in some young individuals, with 2-3 pairs of secondary veins, basally nervate, membranaceous, ciliolate-serrulate; domatia free from the leaf blade, narrowly ovoid to broadly fusiform, the apex attenuate, 1.5-3.5 cm long x 0.4-1.0 cm wide. Inflorescence a terminal panicle, of 10 to >30 flowers, 5-13 cm long, the axis magenta, flattened. Flowers on pedicels 2-3 mm long, not flared at the apex, subtended by lanceolate bracts, caducous, 0.5-0.7 x 0.1 mm, or occasionally, persistent 12-18 x 2-3 mm; hypanthium infundibuliform, 4.0-5.5 mm long, sparsely glandular setose, with a few caducous stellate trichomes; sepals broadly triangular, fused at the base 0.7-1.5 mm, 0.5-2.0 mm long, calyx teeth narrowly triangular, projecting above the sepals, sparsely setulose, 0.5-3.0 mm long; the ring inside the torus glabrous. Petals 5, oblong ovate, 7-10 x 4-7 mm, base attenuate, slightly emarginate, smooth, glabrous, greenish yellow to pale cream. Stamens all of the same size, the filaments 4 mm long, glabrous; anthers yellow; the connective with a dorsal-basal blunt tooth; thecae 4.5-6.0 mm long, opening by a ventrally inclined pore. Ovary 3-locular, 1/2 inferior, the superior portion terete, the apex truncate; style glabrous or sparsely pubescent at the base, 7.5-9.5 mm long; stigma funneliform, papillate. Fruits globose, 6-9 mm long, black, glandular setulose. The seeds not evident through the pericarp, triangular, 0.8-1.1 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= 17.

    Habitat and Distribution: SE Venezuela, Guyana and NE Brazil. Scrubs and Forests from 0 to 1400 m.

    Phenology: Flowering year round, but mostly March-August.

    Ecology: In general, it is found in the understory of forests, and along rivers and creeks, in moister and more shaded areas than T. guianensis or T. desiliens. Because T. aristata usually inhabits shaded areas, timid ants of the genus Crematogaster often colonize it, although Azteca ants have also been found in its domatia.

    Taxonomy and Systematics: Tococa aristata can be readily distinguished from T. guianensis by its green to yellowish petals and the outer calyx projecting beyond the sepals. Vegetatively, T. aristata is very similar to T. bullifera and T. guianensis, but it usually has longer and denser trichomes on the vegetative and reproductive parts. Some highly pubescent specimens of T. bullifera and T. guianensis have been misidentified as T. aristata, but they can be distinguished by the characters given above.

  • Floras and Monographs

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