Tococa pachystachya Wurdack

  • Authority

    Michelangeli, Fabián A. 2005. (Melastomataceae). Fl. Neotrop. Monogr. 98: 1-114. (Published by NYBG Press)

  • Family

    Melastomataceae

  • Scientific Name

    Tococa pachystachya Wurdack

  • Type

    Type. Venezuela. Amazonas: Cerro La Neblina, 1600 m, 24 Jan 1954, Maguire, Wurdack & Bunting 37368 (holotype NY; isotypes F, K, US, VEN).

  • Description

    Species Description - Shrub, to 0.5-3.0 m tall; stems densely glandular-setose, the trichomes 2.5-3.5 mm long, persistent, the nodes glabrous. Leaves anisophyllous, elliptic to ovate, the larger leaves (7.5-) 10-21 (-26) X (3.5-)6-9.5(-12) cm, the shorter leaves 4-9 X 2-4.5 cm, apex shortly acuminate, base cordate, the sinus up to 6 mm long, adaxial surface adpressed-setose, abaxial surface glandular-setose, the nerves densely setose or pilose, light green, (5-)7-plinervate in the leaves with domatia, the first pair of secondary veins merging with the primary vein at the apex of the domatium, 7-nervate in the leaves without domatia, membranaceous, ciliate-serrulate; petioles (0.5-)l.0-2.5 cm long, glandular-setose; domatia 1/2 to completely immersed in the leaf blade, narrowly ovoid, the apex truncate, 2.0-2.5(-3.5) X 0.7-1.5 cm, strigose in the abaxial surface, the trichomes up to 3.5 mm long, their bases up to 1 mm wide, red or crimson. Inflorescence a terminal raceme of 10-20 flowers, 6-15 (-22) cm long, the axis green, quadrangular, fleshy. Flowers sessile, subtended by persistent bracts, ovate, 2-3.5 X 1.5-1.8 mm; hypanthium globose, 3.0-3.2 mm long, glabrous; outer calyx teeth broadly triangular, adnate to the inner teeth, terminated in 1 or 2 glandular setae up to 2.5 mm long, inner calyx teeth broadly deltoid, connate 2/3 to 4/5 of the length, 1.01.8 mm long; the ring inside the torus glabrous; petals 5, oblong, 6.5-7.5 X 4.0-4.5 mm, base oblong to slightly attenuate, truncate, smooth, glabrous, orange to brown; stamens all the same size; filaments 4 mm long, glabrous; anthers yellow; the connective without a dorsal-basal blunt tooth; thecae incurved, 3.5-4.0 mm long, opening by a ventrally inclined pore; ovary 4-locular, 2/3 inferior, the superior portion sulcate, the apex broadly conical, truncate; style glabrous, 6.0-7.5mm long; stigma funnelform to capitate, papillose. Fruits globose, 4-6 mm long, purple, glabrous; seeds not evident through the pericarp, triangular, 0.7-1.3 mm long, without capitate trichomes in the raphal area, without sculpturing, anticlinal walls straight, periclinal walls flat, boundaries between periclinal walls flat.

  • Discussion

    Tococa pachystachya is easily distinguished from all other species by its quadrangular racemose inflorescences, orange to brownish petals, and pubescence of the domatia. The morphological cladistic analysis shows it to be nested within the Tococa sensu stricto clade, in spite of the anther morphology being fairly different from that of other species. However seed and calyx morphology resembles that of other species of Tococa sensu stricto.

    Wurdack annotated one specimen from Neblina (M. Nee 30648) as T. pachystachya var. glabrata, but this specimen corresponds with little doubt to T. erythrophylla.

    Even though T. pachystachya has a very restricted distribution, it is locally abundant.

  • Distribution

    S Venezuela and N Brazil, Cerro La Neblina and Cerro Aracamuni, endemic in cloud forests, tepui scrubs, and ravines from 75-2100 m.

    Amazonas Venezuela South America| Amazonas Brazil South America|