Haemodoraceae R.Br.

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

Morphology

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 .

Distribution

Distribution in the Neotropics

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

General Description

Number of genera

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

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.

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.

Diagnostic

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

Distinguishing characters (always present)

• Perennial herbs.
• Leaves distichous, equitant, parallel-veined.
• Inflorescence a terminal thyrse.
• Indument of inflorescence and floral parts (if present) composed of simple hairs.
• Tepals 6, in 2 whorls.
• Ovary 3-locular.
• Placentation axile.
• Fruit a loculicidally dehiscentcapsule.

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.
• Ovarysuperior 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.

Literature

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.