Monographs Details:
Authority:

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

Melastomataceae
Synonyms:

Microphysca rotundifolia Triana
Description:

Species Description - Shrub, to 0.2-1.2(-5) m tall; stems with a mix of caducous lepidote trichomes and glandular setae 1.5 mm long, the nodes glabrous. Leaves anisophyllous, oblong-elliptic to round, the larger ones 4-9(-11) X 3-4.5(-5) cm, the smaller ones 2-7 X 1-3 cm, apex broadly obtuse to round, base acute to round or subcordate, adaxial surface with glandular setae up to 8 mm long, abaxial surface with a mix of short lepidote hairs and long glandular setae, up to 6 mm long, light green, 5-7-plinervate, those without domatia occasionally 5-7-nervate, the margin entire to ciliate-serrulate; petioles 0.3-1.2 (-2.5) cm long, glandular-setose; domatia present in some of the leaves, but not all, 1/2 to completely immersed in the leaf blade, scrotiform, (1.0-)2.0-4.0 X (1.0-)1.5-3.0 cm with glandular setae up to 15 mm long. Inflorescence a cyme of 3-6 flowers, terminal but quickly becoming axillary by overgrowth of the lateral meristem, 0.5-3 cm long, the axis green, terete, densely stellate-pubescent. Flowers on pedicels 2-3 mm long, flared at the apex, subtended by persistent bracts, subulate, 1-2.5 X 0.2 mm; hypanthium broadly conical, 3-3.5(-40) mm long, sparsely glandular-setose, with a few caducous stellate trichomes and sessile glands; outer calyx teeth projecting downwards along the hypanthium and laterally compressed, forming "wings" that project perpendicularly 1.0-1.2 mm, glandular-setose at the margins, inner calyx teeth flattened, 1.5 mm long, connate at the base 0.8-1.0 mm; the ring inside the torus glabrous; petals 5, very rarely 4, ob-ovate to oblong, 10.5-13.0(-14.5) X 4.5-6.5 mm, base truncate to obtuse, emarginate, smooth to sparsely granulóse, glabrous, bright red or pink; stamens all the same size; filaments 5.5-6.0 mm long, glabrous; anthers yellow; the connective with a dorsal-basal blunt tooth; thecae 3.0-3.5 mm long, opening by a dorsally inclined pore; ovary 3-locular, completely inferior, the apex with sparse, sessile, clavate glands; style glabrous, 6-7(-8.5) mm long; stigma truncate to slightly funnelform. Fruits globose, 3.5-4.5 mm long, black, glabrous to sparsely glandular-setose; seeds not evident through the pericarp, truncate-obovate, 0.8-1.3 mm long, without capitate trichomes in the raphal area, without sculpturing, anticlinal walls straight, periclinal walls flat, boundaries between periclinal walls raised.

Discussion:

Tococa rotundifolia is related to T. macrosperma with which it shares the highly developed pubescence of leaf blades and domatia surfaces, pseudoaxillary inflorescences, red petals, and many aspects of seed morphology. However, T. rotundifolia can be distinguished by the winged calyx and the shape and size of the leaves.

This species was originally described in Microphysca by Triana (1871) and was transferred into Tococa by Wurdack (1969b), after it had been left in nomenclatural limbo by the transfer by Macbride (1941) of the type species of Microphysca into Tococa.

The description of Microphysca rotundifolia includes a note at the bottom as “Myrmidone rotundifolia, Spruce mss” (Triana, 1871). Triana cited Spruce’s notes in a number of other descriptions (effectively causing those species to have Spruce ex Triana as their authorities). It is possible that he did not base his description of Microphysca rotundifolia on Spruce’s manuscript, or that he decided to exclude Spruce’s name, because he was putting the species in a different genus. Therefore, it is not clear if Triana based his description on Spruce’s manuscript and whether the basionym authorities should be Spruce ex Triana. Because there is no obvious solution to this problem, I have chosen to leave Triana as the sole authority of the basionym, following traditional usage.

The type specimen of T. rotundifolia is annotated as coming from San Carlos de Río Negro, in northern Brazil, but this locality is actually in Venezuela. Tococa rotundifolia is locally abundant at San Carlos, where Spruce spent considerable time during his trip, and it surely is the type locality for this species.

Tococa rotundifolia has a very narrow distribution, both geographically and ecologically, but it is locally abundant where it occurs.

The anthers of T. rotundifolia are heavily preyed upon by pollen robbers such as Trigona bees (Renner 1983). This phenomenon seems to occur more often in this species than in other sympatric species of Tococa.
Distribution:

Guainía Colombia South America| Vaupés Colombia South America| Amazonas Venezuela South America| Amazonas Brazil South America|