Tococa desiliens Gleason
-
Authority
Michelangeli, Fabián A. 2005.
(Melastomataceae). Fl. Neotrop. Monogr. 98: 1-114. (Published by NYBG Press) -
Family
Melastomataceae
-
Scientific Name
-
Type
Type. Guyana (British Guayana): in sandy forest skirting the Kaieteur Savannah, 400 m, Sep 1937, Sandwith 1426 (holotype K; isotypes NY, U).
-
Description
Species 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. 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, 5-nervate, chartaceous, entire to obscurely crenulate, ciliate; petioles (1.5-) 3-7 cm long, glandular-setose; 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; outer calyx teeth highly reduced, often terminated in a caducous glandular seta less than 1 mm long, inner calyx teeth obscurely 5-lobed, truncate, 1.5-1.8 mm long; the ring inside the torus glabrous; petals 5, oblong-obovate, 5.5-7.0 X 3.5-4.0 mm, base attenuate, emarginate, pruinose, glabrous, pink, turning white at anthesis; stamens all the same size; 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 trüncate. Fruits globose, with the calyx persistent and slightly reflexed, 7-8 mm long, black, glabrous to sparsely glandular-setose; 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.
-
Discussion
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 domada and has fine-setose pubescence resembling that of T. aristata more than that of T. guianensis. The terete ovary is shared with most other nonmyrmecophilous species of Tococa sensu stricto, but not 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. -
Distribution
Kaiteur region of Guyana, endemic to savannas and low forests from 150-600 m.
Potaro-Siparuni Guyana South America|