Tococa desiliens Gleason

  • Family

    Melastomataceae (Magnoliophyta)

  • Scientific Name

    Tococa desiliens Gleason

  • Primary Citation

    Kew Bull. 1939: 551. 1940

  • Type Specimens

    Specimen 1: Isotype -- N. Y. Sandwith 1426, 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: Guyana (British Guayana): in sandy forest skirting the Kaieteur Savannah, 400 m, SEP 1937, Sandwith 1426 (holotype K; isotypes NY, U).

    Description: Shrub, to 2-4 m tall. Stems slightly flattened when young, sparsely to densely fine-glandular setose, the trichomes 2-3 mm long, persistent, the nodes glabrous. Petioles (1.5-)3-7 cm long, glandular setose. Leaves isophyllous, ovate-oblong to elliptic-oblong, (6-) 9-15 x 5-8 cm, apex shortly acuminate, base obtuse to round, adaxial surface adpressed-setose, abaxial surface sparsely glandular pubescent, hirsute to glandular setose on the primary and secondary veins, green, with 2 pairs of secondary veins, basally nervate, chartaceous, entire to obscurely crenulate, ciliate; domatia absent. Inflorescence a terminal panicle of 12-35 flowers, 7-14 cm long, the axis flattened, sparsely glandular setose. Flowers on pedicels less than 1 mm long, flared at the apex, subtended by caducous bracts, lanceolate, 1.0-1.5 x 0.2 mm; hypanthium conical, 4.5-5.0 mm long, sparsely to moderately fine-setose, the trichomes glandular and eglandular; sepals obscurely 5-lobed, truncate, 1.5-1.8 mm long, calyx teeth highly reduced, often terminated in a caducous glandular setae less than 1 mm long;; the ring inside the torus glabrous. Petals 5, oblong-obovate, 5.5-7.0 x 3.5-4.0 mm, base attenuate, emarginated, pruinosus, glabrous, pink, turning white at anthesis. Stamens all of the same size, the filaments 5.0-5.5 mm long, glabrous; anthers yellow; the connective with a dorsal-basal blunt tooth; thecae 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, 9.5-11.0 mm long; stigma truncate. Fruits globose, with the calyx persistent and slightly reflexed, 7-8 mm long, black, glabrous to sparsely glandular setose. The seeds not evident through the pericarp, triangular, 0.6-1.2 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: Endemic to the savannas and low forest of the Kaiteur region in Guyana from 150 to 600 m.

    Taxonomy and Systematics: Tococa desiliens is very similar in vegetative and floral morphology to some forms of T. guianensis with truncate or highly reduced calyces. However, T. desiliens lacks domatia and its fine-setose pubescence resembling that of T. aristata more than that of T. guianensis. The terete ovary is shared with most other non-myrmecophilous species of Tococa sensu stricto, rather than that of T. guianensis, or closely related species. Even though T. desiliens seems to be restricted to a small area in the Kaiteur, the number of collections and amount of duplicates in different herbaria seem to indicate that this species is locally common.

  • Floras and Monographs

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