Neotropical Erythroxylaceae

Maria Iracema Bezerra Loiola

Universidade Federal do Rio Grande do Norte, Natal, Brazil. 

Description

Glabrous shrubs or small trees. Branchlets erect to spreading, distichous or not, consisting of both long and short shoots. Stipules present, intra-petiolar, striate-nerved or non-striate, often 2 or 3-setulose at apex, persistent or caducous; cataphylls distichous, produced at base of new twigs, in form similar to foliar stipules.  Leaves simple, entire, alternate, petiolate or short-petiolate, pinnately veined.  Inflorescences fasciculate at nodes, sometimes short-pedunculate, with 1-many flowers. Flowers pedicellate, rarely short-pedicellate, small, actinomorphic, bisexual or unisexual, often heterostylous, in axils of leaves or cataphylls, subtended by small scarious bracteoles; calyx lobes 5, persistent, valvate, sepals united below; petals 5, free, alternate with sepals, imbricate in bud, caducous, usually appendaged on the adaxial surface with a 2-lobed ligule; stamens 10 in 2 whorls of 5, the outermost alternate with the petals, the filaments united at the base and usually forming a short tube surrounding the ovary, persistent, anthers 2-locular, longitudinally dehiscent; ovary superior, 3-locular, usually with only one locule ovuliferous; ovule solitary, axillary, pendulous, anatropos, epitropous, styles 3, free or partly connate at base, stigmas capitate. Fruits small, drupaceous and one-seeded. Seeds with straight embryo, with or without endosperm.

Notes on delimitation

  • Recent molecular studies, supported by various morphological and anatomic characters, have shown affinity between Erythroxylaceae and Rhizophoraceae, and suggest that they belong to the order Malpighiales, sensu APG I (1998).
  • In the classification proposed by the APG II (2003), the large affinity and the set of characters shared by both families led Erythroxylaceae and Rhizophoraceae to be considered, optionally, as a single family.
  • The main characters shared by the two families are: alkaloids from the tropane and pyrrolidine groups, the presence of colleters, terminal buds protected by stipules and green embryos.

Distribution in the Neotropics

  • Erythroxylum P.Browne - Mexico, Mesoamerica, Caribbean, South America.

Distinguishing characters (always present)

  • Stipules intra-petiolar.
  • Stamens united at the base by filaments and usually forming a short tube.

Other important characters

Key differences from similar families

  • Stamens 10, biseriate (5 and uniseriate in Linaceae).

Number of genera

One genus: Erythroxylum with 187 species native to the Neotropics.

Notable genera and distinguishing features

Erythroxylum

Status

  • Erythroxylum (Native, cultivated).

General notes

  • Some native species of Erythroxylum, referred to in the literature as having pharmacological potential because they contain alkaloids, flavonoids and terpenoids, are widely used in medicine.  Among these is E. coca Lam., from which the cocaine alkaloid is extracted.  It has been used since 1879 as a local anaesthetic and for terminally ill patients (Brompton cocktail), but mainly illegally as a recreational drug sold in major urban centers to a considerable addict population.  This species has long been used as a ritualistic psychoactive medicinal plant by a host of South American tribes.
  • In Brazil, Erythroxylum vacciniifolium Mart., popularly known as "catuaba", is used to stimulate the central nervous system in addition to exhibiting aphrodisiac properties.
  • E. pelleterianum A. St.-Hil. is used to treat stomach pains.
  • E. myrsinites Mart. and E. suberosum A. St.-Hil. are used in the tanning industry.

Important literature

El-Imam, Y. M. A., Evans, W. C. & Plowman, T. 1985. Alkaloids of some south american Erythroxylum species. Phytochemistry 24 (10): 2285-2289.

Exell, A. W. & Mendonça, F. A. 1950. Nectaropetalaceae, fam. nov. Bol. Soc. Brot. 24: 105.

Gentner, W.A. 1972. The genus Erythroxylum in Colombia. Cespedesia 1(4): 481-554.

Loiola, M. I. B. 2004. Flora de Grão Mogol, Minas Gerais: Erythroxylaceae. Boletim de Botânica da Universidade São Paulo 22(2): 101-108.

Loiola, M. I. B.; Agra, M. F.; Baracho, G. S. & Queiroz, R. T. 2007. Flora da Paraíba, Brasil: Erythroxylaceae. Acta Bot. Bras. 21(2): 473-487.

Plowman, T. 1984. New taxa of Erythroxylum (Erythroxylaceae) from the Amazon Basin. Supl. Acta Amazonica 14 (1/2): 117-143.

Plowman, T. 1987. Ten new species of Erythroxylum (Erythroxylaceae) from Bahia, Brazil. Fieldiana, Botany 19: 1-41.

Plowman, T. C. 1989. Ertythroxylaceae. In: G. Harling & L. Anderson (eds.), Flora of Ecuador 36: 1-32.

Plowman, T. C. & Berry, P. E. 1999. Flora of Venezuela Guayana 5: 59-71.

Plowman, T. C. & Hensold, N. 2004. Names, types and distribution of neotropical species of Erythroxylum (Erythroxylaceae). Brittonia 56(1): 1-53.

Schulz, O. E. 1907. Erythroxylaceae. In: A. Engler (Ed.). Das Pflanzenreich. 4(134): 1-164.

How to cite

Loiola, M.I.B. (2009). Neotropical Erythroxylaceae. 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/Erythroxylaceae.htm.