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Common name:  None.

Latin name and synonyms: Sipapoantha Maguire & Boom (1989)

Etymology: The genus Sipapoantha is named after the mountain Cerro Sipapo in southern Venezuela.  The ending -antha means flower.

Species:   Two species.

Distribution:   Cerro Sipapo, in Amazonas State, Venezuela, and in Roraima state, Brazil.

Habitat:  Mountain summits.

Characteristics: Annual herb. Stem quadrangular, often with 4 narrow wings. Leaves mainly at the base in a rosette or nearly so, smaller toward higher up, sessile, obovate (lower leaves) to broadly elliptic (upper leaves), very thick and leathery; base narrowly attenuate; apex obtuse; margin strongly recurved. Inflorescence terminal, cymose, 1–3 branches, 1–7-flowered. Flowers 5-merous, slightly zygomorphic (anthers aggregated in upper part of corolla mouth and style bent). Calyx campanulate, divided ca. 2/3 of the length, thick and leathery, persistent, lobes oblong, obtuse, with a dorsal thick ridge, obtuse. Corolla showy and large, funnelform, dark blue to purple, thin, deciduous in fruit, lobes elliptic to circular, obtuse, corolla bud apex rounded. Stamens inserted very close to base of corolla tube; filaments of unequal length, widened at the base; anthers lanceolate, sagittate, straight after anthesis, versatile, with a sterile apical appendage. Pollen in tetrads; exine reticulate, small globules. Ovary with glandular disk; style long, slender, deciduous in fruit; stigma bilamellate; lobes broadly circular. Capsule woody, oblong, dehiscing medially, nodding. Seeds angular, not winged, testa cells concave with band-like thickenings.

Evolution and related plants:   

Economic uses:  None known.

Notes: 

Accepted species (synonyms in parenthesis) and their distribution:

References and publications: 

Maguire, B. & B. M. Boom. 1989. Gentianaceae, part 3. Pp. 2-56. In: B. Maguire & collaborators, editors. The Botany of the Guayana Highland – Part XIII. Mem. New York Bot. Gard. 51.

Struwe, L., J. W. Kadereit, J. Klackenberg, S. Nilsson, M. Thiv, K. B. von Hagen, & V. A. Albert. 2002. Systematics, character evolution, and biogeography of Gentianaceae, including a new tribal and subtribal classification. Pp. 21-309. In: L. Struwe & V. A. Albert (eds.), Gentianaceae: Systematics and Natural History, Cambridge University Press, Cambridge.

Struwe, L., P. J. M. Maas, O. Pihlar, & V. A. Albert. 1999. Gentianaceae. Pp. 474-542. In: P. E. Berry, K. Yatskievych, & B. K. Holst, editors. Flora of the Venezuelan Guayana, vol. 5. Missouri Botanical Garden, St. Louis.  (images)

© Lena Struwe, 2004-2011