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Species:   Only one species, Saccifolium bandeirae.

Distribution:   This rare species is only found on the peaks of the mountain of Sierra de la Neblina, on the border between Venezuela and Brazil, close to Rio Negro.

Habitat:  Saccifolium is a high-altitude plant (2700-3000 m above sea level) and grows among rocks and on cliffs.

Characteristics:  Shrub up to 60 cm tall, branches with lots of corky bark. Leaves tightly arranged, opposite or possibly alternate, sac-shaped, partly translucent, and with glands on the lower surface [Struwe et al., 1998]. Flowers 5-merous, solitary, in the axils of leaves. Calyx rotate, lobes nearly free (calyx divided almost to the base), with enlarged glands at base of calyx (possibly colleters). Corollas tubular, widened in the middle; corolla lobes short and imbricate in bud. Stamens inserted in the lower part of the corolla tube, filaments flattened. Ovary sessile, unilocular; placentas deeply protruding. Style long and thin. Fruits not known (never collected as mature). Seeds from immature fruits not winged.

Evolution and related plants:   Saccifolium was initially placed in its own monotypic family, Saccifoliaceae [Maguire & Pires, 1978], but recent phylogenetic studies has shown it is part of the most basal (oldest) tribe of the Gentianaceae [Thiv et al., 1999]. Closely related to Saccifolium are such different and diverse plants as Curtia, Hockinia, Tapeinostemon, and the chlorophyll-less Voyriella. Earlier reports that Saccifolium was related to Gentiana were erroneous.

Economic uses:  None known.

Notes: The unique leaves of Saccifolium are not found in any other plant.  They look like upside-down small sacs with a round opening (images).

Accepted species (synonyms in parenthesis) and their distribution:

References and publications: 

Maguire, B. & J. M. Pires. 1978. Saccifoliaceae – a new monotypic family of the Gentianales. Pp. 230-245. In: B. Maguire & collaborators, editors. The Botany of the Guayana Highland – Part X. Mem. New York Bot. Gard. 29. 

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)

Thiv, M., L. Struwe, V. A. Albert, & J. W. Kadereit. 1999a. The phylogenetic relationships of Saccifolium bandeirae Maguire & Pires (Gentianaceae) reconsidered. Harvard Pap. Bot. 4: 519-526.

© Lena Struwe, 2004