Metaporana
Accepted name/Authority/Place of publication:
METAPORANA N.E. Br., Kew Bull. Misc. Inform. 1914: 168. 1914.
Tribe:
Poraneae
Type Species:
Metaporana densiflora (Hallier f.) N.E. Br. [chosen by Verdcourt, Kew Bull. 23: 291. 1969.]
Habit:
Bushy shrubs or woody climbers; stems slender, rarely glabrous.
Leaves:
Leaves simple, petiolate, blade ovate, obovate, elliptic-oblong or lanceolate, base rarely cordate.
Inflorescences:
Thyrsoid, axillary or terminal, pedunculate, many-flowered; bracts frequently foliaceous.
Flowers:
Sepals unequal, not enlarged in fruit. Corolla medium-sized, in bud induplicate-valvate, white or yellowish white, 5-lobed, tube subcylindrical, about as long as calyx, lobes erect; midpetaline bands usually pubescent outside. Stamens and style exserted, filaments equal, basally attached to corolla tube and often broader, filamentous above, anthers elliptic-oblong, dorsifixed. Pistil exserted; disc cylindrical or cupuliform, very lobed; ovary globose, glabrous, 2-celled, each cell 2-ovulate; styles 2, free to the base; stigmas capitate and appearing “cottony”.
Pollen:
Ellipsoidal or spheroidal, 3-colpate, surface finely psilate.
Fruits:
Capsule subglobose to ovoid, 2-celled, 3- or 4-valved, sometimes only dehiscing at the base.
Seeds:
2-4, broadly ovoid, glabrous.
Distribution:
Africa, Madagascar. map
Countries:
Madagascar
Kenya
Uganda
Tanzania
Congo
Zaire
Yemen (Socotra islands)
Number of Species:
6
References:
Brown, N. E. 1914. Diagnoses Africanae: LIX. Bulletin of Miscellaneous Information, Kew 1914: 167-171.
Deroin, T. 2001. Flore de Madagascar et des Comores, Convolvulaceae 171: 42–52.
Verdcourt, B. 1969. Corrections and additions to the 'Flora of Tropical East Africa—Convolvulaceae': III. Kew Bulletin 23: 291.
Verdcourt, B. 1974. The genus Metaporana (Convolvulaceae) in Madagascar. Kew Bulletin 29: 333-340.
Contributors:
Metaporana is likely to be a paraphyletic genus, because some of the species have an enlarged, accrescent calyx while others do not. When N.E. Brown named the genus, he defined it largely on the basis of a non-accrescent calyx. Yet M. densiflora (the type species of the genus) has an enlarged calyx, as does the Socotran species. The Madagascan species have a different fruit type as well. This is a genus that requires a thorough revision and careful scrutiny of the characters used to define it.