Monographs Details: Miconia cowanii Wurdack
Authority: Maguire, Bassett & Wurdack, John J. 1961. The botany of the Guayana Highland--part IV (2). Mem. New York Bot. Gard. 10: 1-87.
Family:Melastomataceae
Scientific Name:Miconia cowanii Wurdack
Description:Latin Diagnosis - M. lepidotae D C . affinis sed cum foliis proportionaliter angustioribus, pube cinerea, antherarum connectivo subtus prominenter expanso. Sect. Miconia subsect. Seriatiflorae. Rami acute tetragoni cum petiolis foliis subtus inflorescentiis hypanthiisque pube albido-cinerea stellato-lepidota dense obsiti. Petioli 1-2.5 cm longi; lamina vix coriacea 11-26 X 3-8.5 cm elliptica apice graditer vel subabrupte acuminata basi acuta 5-nervata vel paulo (ad 3 mm) 5-plinervata nervis exterioribus tenuibus nervis secundariis supra vix impressis subtus anguste elevatis nervis tertiariis subtus laxe reticulatis margine integerrima supra glabra. Inflorescentia paniculata 12-28 cm longa cum ramulis extremis secundifloris; flores 5-meri sessiles. Hypanthium (ad torum) 1.9-2.1 mm altum; calycis tubus 0.5 mm altus lobis 0.4 mm altis late deltoideis dente inconspicuo extus ornatis. Petala 2.6-3.1 X 1.5-1.8 mm apice oblique rotundata glabra eciliata. Stamina paulo dimorphica; filamenta 2.2-2.5 mm longa. Stamina antesepala: thecae 1.8-2 mm longae connectivo sub loculis antice 0.2-0.3 mm prolongato et in appendice cordiformi 0.6-0.9 mm longa lataque terminato. Stamina intersepala: thecae 1.6 mm longae, connectivo antice 0.5 mm prolongato et lateraliter bidentato postice sub insertionem filamenti in appendice 0.4 mm longa acuta prolongato. Stylus 3.5 X 0.2 mm apice clavatus cum stigmate 0.5-0.6 mm diam.; ovarium 3-loculare apice in conum glabrum 0.2 mm altum prolongatum; fructus (vix immaturus?) globosus non striatus ca. 4 mm diam. cum calyce persistente.

Distribution and Ecology - BRAZIL: Amapa: Serra do Navio, Rio Amapari, occasional in lowland forest along trail to Serra do Yiado via Water Supply Dam; tree 7 m tall, flowers white; 17 Nov 1954, B. S. Cowan 38399 (holotype, NY); Serra do Navio; tree 6 m on southeast lower slopes of Chumbo Ore Body, Cowan 38071; tree 10 m on lower slopes of Observatorio Ore Body, Cowan 38160 (paratypes).

Discussion:The leaf blades of M . lepidota have a length/width ratio of about 2 rather than 3-4, as well as predominantly fulvous stellate-lepidote pubescence rather than predominantly silvery white scales with only scattered fulvous ones; the stamen connectives of M. lepidota are proportionately longer-prolonged basally with much smaller basal expansion. M . cowanii has somewhat the aspect of M. argyrophylla D C , which however has an indiscrete indumentum and glandular-ciliate petals. M . punctata (Desr.) Don has a tawny indument, firmer leaves, and anthers widest apically (rather than oblong with a relatively smaller pore), at least in West Indian material.