Neotropical Desfontainiaceae

Description

Erect or sprawling evergreen shrubs, or small trees, 1-4m tall, with stiff branchlets, sometimes decumbent. Leaves simple, opposite, decussate, petiolate, leathery, margin serrate, venation prominent, pinnate, the mid-vein occasionally covered in hairs; stipules inter-petiolar, caduceus leaving scar. Flowers hermaphroditic, mainly solitary but also aggregated in inflorescences, terminal and in leaf axils, pentamerous; calyx lobes free to the base and with overlapping margins in bud; corolla sympetalous, actinomorphic with a long tube, lobes ovate to circular, glabrous; stamens 5, alternating with the corolla lobes, adnate just below the mouth of the corolla tube, anthers longitudinally dehiscent, basifixed; ovary superior, syncarpous with 5 carpels, locules incomplete with 5 at base 1 at apex, ovules many. Fruit ovoidal to globose, white berries (green when mature); seeds many, dark brown, shiny.

Notes on delimitation

• Desfontainiaceae is currently unassigned in the Asterids. It has previously been placed in the orders Dipsacales (Backlund 1996), Gentianales (Cronquist 1981) and in the families Gentianaceae (Don 1831) and Loganiaceae (Leeuwenberg 1969).
• It has also been suggested that Desfonainiaceae could be synonymised with the Columelliaceae (Stevens, 2008) due to similarities in wood anatomy, distribution, habit, large, showy, pentamerous flowers and the many seeds.

Distribution in the Neotropics

• Found from Patagonia (0-1200m) northward along the Andes, growing at higher altitudes in tropical regions (2000-4000m) to Colombia and Costa Rica, preferring a cool, moist climate.

Distinguishing characters (always present)

• Leaves opposite, simple, leathery, margins serrate.
• Mid vein prominent as are secondary and tertiary.
• Perianth 5-merous with red to yellow tubular corolla.
• Fruit globose to ovoidal.

Other important characters

• Leaves dry blackish-brown.

Key differences from similar families

• Columelliaceae have an epigynous flowers, zygomorphic corolla, 2 stamens and capsular fruit.
• Gelsemiaceae with leaf blade margins do not have spine like teeth.
• Fagraea Thunb. and Potalia Aubl.in the Loganiaceae have capsular fruit, an inferior ovary and no spine-like teeth around leaf blade.

Number of genera

1. Desfontainia Ruiz & Pav. is by some scientists considered to have only one very variable species D. spinosa Ruiz & Pav.; however at least three species have been described:

• D. spinosa:  Corolla with acuminate lobes, 1.5-2(-3) times as long as calyx lobes, these are always pubescent on back and margin.
• D. fulgens D.Don:  Corolla gradually dilated towards the porrect or half-spreading limb, tube cylindrical, calyx lobes widely oblong, apex rounded, without prominent midrib.
• D. splendens Bonpl.:  Corolla abruptly dilated into half spreading or spreading limb, tube cylindrical, calyx lobes widely oblong or oblong acuminate, apex rounded to acute.

Status

• Native and widely cultivated in cold, wet climates without a dry season for uses as varied as dying fabric, ornamental horticulture and as a shamanic tea.

General notes

• Takes its name from M. Desfontaines, a French botanist.

Important literature

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

Backlund, A., & Bremer, B. 1997. Phylogeny of the Asteridae s. str. based on rbcL sequences, with particular reference to the Dipsacales. Pl. Syst. Evol. 207: 225-54.

Bell, C. D., Edwards, E. J., Kim, S.-T.& Donoghue, M. J. 2001. Dipsacales phylogeny based on chloroplast DNA sequences. Harvard Papers Bot. 6: 481-499.

Cronquist, A.1981. An integrated system of classification of flowering plants. Colombia University Press, New York.

Don, D. 1831. On the characters and affinities of certain genera, chiefly belonging to the flora Peruviana. Edinb. New. Philos.J. July-Sept. 1831: 271-280.

Heywood, V.H., Brummitt, R.K. Culham, A. and Seberg, O. (eds.). Flowering plant families of the world, p.123. Kew: Royal Botanic Gardens, Kew.

Leeuwenberg, A.J.M. 1969. Notes on American Loganiaceae IV. Revision of Desfontainia Ruiz et Pav. Acta Bot. Neerl. 18: 669-79.  

Maas, P. J. M. & Westra, L. Y. Th. 2005. Neotropical Plant Families. 3rd ed. P. 132. A.R.G. Gantner Verlag K.G., Ruggell.

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

Struwe, L. 2004. Desfontainiaceae. Pp. 126-7. 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.

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

Weigend, M. 2001. Desfontainia Ruiz & Pav. (Desfontainiaceae) revisited: A first step back towards alpha-diversity. Bot. Jahrb. 123:281-310.

How to cite

Every, J.L.R. (2009). Neotropical Desfontainiaceae. 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/Desfontainiaceae.htm.