Brachyotum gleasonii Wurdack
-
Authority
Wurdack, John J. 1953. A revision of the genus Brachyotum (Tibouchineae-Melastomataceae). Mem. New York Bot. Gard. 8 (4): 343-407.
-
Family
Melastomataceae
-
Scientific Name
-
Description
Latin Diagnosis - Trichomata minute modiceque aspera. Ramuli novelli obscure quadrangulati cum petiolis pedicellisque dense hirsutuli vel laxo-brevi-strigosi. Petiolus (6-)10-25 mm. Lamina 30-75 x 10-35 mm. elliptica vel lanceolato-elliptica apice acuta vel anguste obtusa basi obtusa, nerviis primariis 5 (aut 3-5 distinctioribus cum marginum duobus additis plus minusve indistinctis) supra anguste impressis subtus expressis secundariis utrinque 20-25 supra et subtus ab piliis occultis; supra dense laxo-gracili-strigosa, pilis 3-11/mm.2 basi per l/s-V4 adhaerentibus; subtus modice hirsuta vel laxo-gracili-strigulosa 5-15/mm.2, glandulis solitariis sparsis. Flores 5-meri plerumque terni vel triterni, cum foliis duobus ad basim dichasii. Pedicellus sub bracteis 3-10 mm., super 2-4(-10) mm.; bracteae 5-9 x 2-4.5 mm. ellipticae caducae vel persistentes, supra in parte 1/3-2/3 apicali strigulosae basim versus glabrae, subtus modice strigulosae. Hypanthium 6-9 x 7-9 mm., medio 0.4-0.5 mm. crassum, densissime hirsutum vel laxo-strigosum, pilis 8-20/mm.2 et ad 2 mm. longis. Sepala 5-9 x 4.5-6 mm. ovata vel oblongo-ovata apice late acuta vel anguste obtusa et breviter apiculata base per 0.7-1 mm. cohaerentia, sinu acuto. Petala 16-19 x 14-18 mm. obovata apice rotunda vel leviter obliquo-truncata, ciliis 0.2-0.7 mm. (uno terminali 0.7-1.1 mm.) non-glandulosis. Filamenta 7-9 mm.; antherae 5.5-8 mm.: connectivum basi antherae non vel vix (per 0.1 mm.) ab anthera liberum. Stylus 20-25 mm. longus, basi 1-1.4 mm. apice 0.5-0.7 mm. diam., per 2-5 mm. exsertus. Ovarium 6-7.5 x 4-5 mm. apice per 3-4 mm. dense strigulosum, lobis apicalibus super loculos 0.5-2 mm.
Distribution and Ecology - Distribution: central Ecuador, alt. 3000-3100 m.
-
Discussion
Type Collection and Locality: Camp E-4118 (HOLOTYPE NY); Ecuador, Chimborazo- Canar border (western escarpment), near Pimo, alt. 10200-10400 ft., 9 Jul. 1945' "Tree 6 m. Lvs dark green, nitid under pubescence above; bright green below. Stems, petioles, and veins below deep red. Calyx deep crimson. Corolla white, faintly tinged with yellow, of the tubular type which is pendant and does not open fully."
Cogniaux had annotated the Sodiro collections, one as a new species and the other as a variety of B. ledifolium, but these names were never published. B. gleasonii is closely related to and intermediate between B. racemosum and B. ledifolium. From the latter, the cited collections may be distinguished by the much less shaggy trichomes, larger leaves, longer hypanthial pubescence, usually larger pedicellar bracts, generally larger flowers, and denser ovary pubescence. Especially striking is the absence of the graduated short pseudo-stellate hairs so characteristic of the lower leaf surface in B. ledifolium; these hairs, in B. gleasonii, are slender, rather flexuous, and inconspicuously roughened.