Neotropical Haemodoraceae

Paul J.M. Maas and Hiltje Maas-van de Kamer.

National Herbarium, Wageningen University Branch, the Netherlands. 

Description

Perennial, herbs, rhizomatose, sometimes stoloniferous or cormiferous, often with red latex. Leaves parallel-veined, distichous, equitant, linear or ensiform, mainly radical, sheathing at the base. Inflorescence a terminal, bracteate thyrse, the partial inflorescences lax or dense cincinni. Indument of inflorescence and floral parts composed of simple hairs or lacking. Flowers actinomorphic to zygomorphic, shortly pedicellate; tepals 6, arranged in 2 whorls, free or basally connate; stamens 1-3, unequal, inserted at the base of the inner tepals, filaments short, basifixed, introrsely and longitudinally dehiscent; staminodes 0-2, inserted at the base of the inner tepals (Pyrrorhiza Maguire & Wurdack) or outer tepals (Schiekia Meisn.); style 1, filiform, stigma simple to slightly 3-lobulate; ovary superior to inferior, 3-locular, ovules 2-many, anatropous, placentation axile, septal nectaries present (except in Xiphidium Aubl.). Fruit a 3-locular, loculicidally dehiscent capsule. Seeds 2-many per locule, tuberculate, hairy, or glabrous.

Notes on delimitation

  • The Haemodoraceae family is placed in the order of Commelinales, together with 2 families which also occur in the Neotropics, namely Commelinaceae and Pontederiaceae.

Distribution in the Neotropics

  • All over the Neotropics, but also in the USA and Canada (Lachnanthes Elliott).

Distinguishing characters (always present)

Other important characters

  • Plants often with red sap in the rhizomes or stolons.
  • Leaves linear to ensiform.
  • Stamens 1-3, unequal.
  • 0-2 staminodes present in 2 genera.
  • Ovary superior to inferior.
  • Ovules 2-many.

Key differences from similar families

Haemodoraceae could easily be confused with Iridaceae because of their distichous, equitant, parallel-veined, narrow leaves. They differ, however, by:

  • The red sap in their underground parts.
  • Unequal stamens.
  • Sometimes having staminodes.

Number of genera

  • Lachnanthes - (1 sp.)
  • Pyrrorhiza - (1 sp.)
  • Schiekia - (1 sp.)
  • Xiphidium - (2 spp.)

Useful tips for generic identification

Key to genera of Neotropical Haemodoraceae

1. Ovary inferior; stamens 3; inflorescence and outer side of tepals densely covered with white, woolly hairs ... Lachnanthes
1. Ovary superior; stamens 1 or 3; inflorescence and outer side of tepals glabrous to hairy, but never covered with woolly hairs ... 2

2. Inflorescence a thyrse, composed of two to four 5-7-flowered cincinni; stamen 1; cormiferous herbs ... Pyrrorhiza
2. Inflorescence a thyrse, composed of many 3-25-flowered cincinni; stamens 3; rhizomatous herbs ... 3

3. Staminodes 2; outer side of tepals hairy; ovary with 3-6 ovules per locule; fruit with 2-4 seeds per locule... Schiekia
3. Staminodes absent; outer side of tepals glabrous; ovary with 7-many ovules per locule; fruit with many seeds per locule... Xiphidium

Status

  • All genera are native in the Neotropics.

General notes

  • The red-coloured pigment often present in the underground parts - arylphenalenone haemocorin - is unique in the Plant Kingdom.

Important literature

Maas, P.J.M. & H. Maas-van de Kamer. 1993. Haemodoraceae. Flora Neotropica Monograph 61: 1-44.

Simpson, M.G. 1998. Haemodoraceae. In: K. Kubitzki  (ed.), The families and genera of vascular plants 4: 212-222.

How to cite

Maas, P.J.M. & Maas-van de Kamer, H. (2009). Neotropical Haemodoraceae. 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/Haemodoraceae.htm.