Neotropical Columelliaceae

Jon L.R. Every

Royal Botanic Gardens, Kew, UK.  

Description

Evergreen shrubs or trees. Leaves simple, opposite, decussate, leathery, the adaxial surface glabrous, the abaxial pubescent, margin entire or serrate, primary venation parallel; stipules leafy, leaving swollen, inter-petiolar scars; bracteoles present. Inflorescences few-flowered, terminal and/or axillary cymes or panicles or flowers solitary. Flowers slightly zygomorphic, (4-)5(-8)-merous; calyx adnate to ovary, calyx lobes gland-tipped; corolla yellow, sympetalous, the lobes imbricate in bud; stamens 2, adnate to the corolla tube, anthers large, basifixed, irregularly plicate and twisted; ovary inferior, syncarpous, with 2 carpels, incompletely 2-locular, stigma 2-4 lobed; placentation essentially parietal, ovules numerous. Fruit septicidal, imperfectly 4-locular capsule with persistent calyx; seeds many, minute, laterally compressed, oblong, smooth.

Notes on delimitation

  • Columelliaceae is currently unassigned in the Asterids. It has previously been placed in various orders: Rosales (Cronquist 1981), Saxifragales (Takhatajan 1983), Hydrangeales (Thorne 1992) and Dipsacales (Backlund 1996). Its closest relative, the monogeneric Desfontainiaceae, could be synonymised with the Columelliaceae (Stevens 2008) due to similarities in wood anatomy, distribution, habit, large, showy flowers and the many seeds.

Distribution in the Neotropics

  • Restricted to the Andes from Colombia to Bolivia from about 1,600 to 3,600 metres above sea level.

Distinguishing characters (always present)

  • The stamens are large, unusually folded, rather like a concertina or fan.
  • Internodes are prominent along the branchlets with opposite leaves.
  • The flowers are slightly zygomorphic and yellow with a distinct calyx and corolla.
  • The ovary is inferior and syncarpous.
  • Fruit, an imperfectly 4-locular capsule.
  • Numerous minute seeds.

Number of genera

  • 1 Neotropical genus: Columellia Vahl.

Status

  • Native, limited to Andean South America.

Important literature

Brizicky, G.K. 1961. A synopsis of the genus Columellia (Columelliaceae). J. Arnold Arbor. 42:363-72.

Stern, W. L., G. K. Briziky, & R. H. Eyde. 1969. Comparative anatomy and relationships of Columelliaceae. J. Arnold Arbor. 50:36-75.                                                                

L. Watson and M. J. Dallwitz (1992 onwards). The Families of Flowering Plants: Descriptions, Illustrations, Identification, and Information Retrieval. Version: 14th December 2000.

Fagerstrom, K. 1994. Columelliaceae, pp. 3-5, in Harling, Gunnar Wilhem, Flora of Ecuador, Opera Botanica, Ser. B., no. 4. University of Goteborg, Sweden.

Maas, P. J. M., & Westra, L. Y. T. 2005. Neotropical Plant Families. 3rd edition. Koeltz, Koenigstein.

Backlund, A. 1996. Phylogeny of the Dipsacales.-Compreh. Summ. Uppsala Diss. Fac. Sci. 243. Uppsala.

Gregory, M. 1998. Columelliaceae, pp. 117-121, in Cutler, D. F., & Gregory, M. (eds), Anatomy of the Dicotyledons, Second Edition, Volume 4, Saxifragales (sensu ArmenTakhtajan 1983). Clarendon Press, Oxford.

Struwe, L. 2004. Columelliaceae. Pp.108-9. In: Smith, N., Mori, S. A., Henderson, A., Stevenson, D. W. and Heald, S. V. (eds.). Flowering Plants of the Neotropics. The New York Botanical Garden, Princeton University Press, Princeton.

V.H Heywood, R.K. Brummitt, Culham, A. and Seberg, O. (eds.). Flowering plant families of the world, Pp.105-6. Kew: Royal Botanic Gardens, Kew.

Stevens, P. F. (2008). Angiosperm Phylogeny Website, version 9. http://www.mobot.org/MOBOT/research/APweb/.

How to cite

Every, J.L.R. (2009). Neotropical Columelliaceae. In: Milliken, W., Klitgård, B. & Baracat, A. (2009 onwards), Neotropikey - Interactive key and information resources for flowering plants of the Neotropics. http://www.kew.org/science/tropamerica/neotropikey/families/Columelliaceae.htm.