Neotropical Rhabdodendraceae

Ghillean T. Prance

Royal Botanic Gardens, Kew, UK. 

Description

Shrubs or small trees.  Leaves entire, alternate, gland-dotted, coriaceous, with small peltate hairs on undersurface; stipules small, subulate or obscure. Inflorescence of supra-axillary racemose panicles or racemes; bracts and bracteoles small and reduced to scales.  Flowers hermaphrodite; receptacle broad, slightly concave; calyx very short, lobes 5 or indistince; petals 5, caducous, sepaloid, oblong or oblong-elliptic, apex rounded or minutely apiculate, minutely punctuate, aestivation imbricate; disk absent; stamens numerous (about 45), filaments short, flattened, persisting after anthers fall, and then recurved; anthers linear, erect, basifixed, caducous, 4-locular, dehiscing longitudinally; ovary sessile, globose, glabrous, unilocular, inserted at base of concave receptacle; ovule 1, basally attached, campylotropous; style arising from base of ovary to one side of it, fairly thick, elongated; stigmatic surface on outermost side ascending from the base or middle. Fruit a small drupe, globose, terminating in a short stripe in cup-shaped receptacle; exocarp thin, crustaceous when dry; endocarp slightly woody.  Seed 1, reniform-globose, exalbuminous, with a thin testa; cotyledons thickly fleshy, conferruminate; radicle small and bent inward towards hilum.

Notes on delimitation

  • The family was often placed in or near Rutaceae and was in the Chrysobalanaceae for a while.
  • It differs in many characters from both families.
  • Molecular and wood anatomy place it near to the Phytolacaceae in the Caryophyllales.

Distribution in the Neotropics

  • Confined to Amazonia, the Guianas and northeastern Brazil.

Distinguishing characters (always present)

Number of genera

  • A single genus, Rhabdodendron Gilg & Pilg. with three species.

Status

  • Native and endemic to the Neotropics.

Important literature

Fay, M.F., Cameron, K.M., Prance, G.T., Lledo, M.D. & Chase, M.W. 1997. Familial relationships of Rhabdodendron (Rhabdodendraceae): plastid rbcL sequences indicate a caryophyllid placement.  Kew Bull. 52: 923-932.

Prance, G.T. 1968. The systematic position of Rhabdodendron Gilg & Pilg. Bull. Jard. Bot. Nat. Belg. 38: 127-146.

Prance, G.T. 1972. Monograph of Rhabdodendraceae. Flora Neotropica 11: 1-22.

Prance, G.T.  2002. Rhabdodendraceae, pp. 339-341. In: K. Kubitzki and C. Bayer (eds.). The Families and  Genera of Vascular Plants, vol. . Springer-Verlag, Berlin.

How to cite

Prance, G.T. (2009). Neotropical Rhabdodendraceae. 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/Rhabdodendraceae.htm.