Neotropical Amaryllidaceae

Alan W. Meerow

USDA-ARS-SHRS, National Germplasm Repository, Miami, Florida, USA. 

Description

Habit: bulbous (rarely rhizomatous), mostly geophytic, perennials, terrestrial, occasionally aquatic or epiphytic, rich in family-specific alkaloids; bulbs tunicate.  Leaves annual or persistent, sessile and linear or lorate, or petiolate and lanceolate to widely elliptic, distichous or spirally arranged; sometimes basally sheathing and forming an aerial pseudostem, usually glabrous, rarely with trichomes; phyllotaxy chiefly distichous, sometime spiralled.  Inflorescence scapose, pseudo-umbellate (reduced helicoid cymes); scape sometimes wholly subterranean, appearing obsolete, terminated by two or more spathaceous, obvolute or equitant, usually marcescent bracts that enclose the flowers in bud (bracts rarely absent); inner bracteoles usually present and successively shorter and narrower.  Flowers 1-many, perfect, frequently large and showy, sessile or pedicellate, each usually subtended by a bracteole, actinomorphic or zygomorphic, generally protandrous; perigone crateriform, salverform, funnelform, tubular or ventricose, consisting of 3 + 3 segments (tepals) connate below into a short or long tube or rarely free to the base; inner tepals generally shorter than the outer; outgrowth of the perigone sometimes present, forming a conspicuous corona (paraperigone), or relatively inconspicuous and consisting of a short callose rim or ring of scales or fimbriae at the throat; stamens 3 + 3, rarely 5 or 18 or more, subequal or varying in length, inserted at the perigone throat or below, the filaments sometimes variously connate or otherwise appendaged, rarely adnate to the style; anthers usually dorsifixed, rarely centrifixed or basifixed, introrse, dehiscing longitudinally or rarely from a terminal pore; style filiform, occasionally strumose, rarely tripartite; stigma capitate, 3-lobed or deeply trifid, usually papillate; ovary syncarpous, tri-carpellate, inferior, tri- (rarely uni-) locular, with septal nectaries; ovules axile or basal in placentation, anatropous, crassinucellate, bi-, uni- or ategmic.  Fruit a loculicidally dehiscent capsule, sometimes indehiscent, rarely baccate; seeds globose or subglobose and fleshy or hard, or flattened and winged, usually with a black or brown phytomelanous testa, sometimes with a caruncular elaiosome at the chalazal end; endosperm with hemicellulose and lipids, in the more derived genera rich in water and/or starch.

Notes on delimitation

  • Multiple DNA sequences indicate that Amaryllidaceae, Alliaceae and Agapanthaceae form a monophyletic group which can be treated as one family. 
  • The AGP II listed both classifications as options. 
  • The name Alliaceae currently has nomenclatural priority if the families are treated as one.
  • A proposal to super-conserve the name Amaryllidaceae has been submitted to the nomenclatural committee of the International Association for Plant Taxonomy.

Distribution in the Neotropics

  • In the Neotropics, the family occurs from Mexico through Central America and the West Indies to Chile and Argentina in South America. Notable areas of diversity throughout this range include eastern Brazil, north-central Chile (outside of the tropical zone, however), and the central Andes of Ecuador and Peru.
  • Hippeastrum Herb. is primarily found in the Andes and eastern Brazil, Hymenocallis Salisb. occurs mostly in Mesoamerica, Clinanthus Herb. is largely endemic to Peru, and Zephyranthes Herb. is broadly distributed. The greatest generic diversity is found in Peru.
  • The Neotropical genera of Amaryllidaceae are chiefly adapted for seasonally dry habitats and some prefer truly xeric environments in which their bulbs may remain dormant for a period longer than they are in active growth (e.g., Leptochiton Sealy, Paramongaia Velarde, some Eucrosia Ker Gawl.). At the other extreme, species have colonized the understory of rain forests (Eucharis Planch. & Linden, Griffinia Ker Gawl.) and aquatic habitats (a number of Hymenocallis, Hippeastrum angustifolium Phil., Crinum L.).
  • The family has also adapted to the high montane tropical climates of the Andes. Certain genera are primarily found at elevations in excess of 2,000 meters; and Clinanthus humilis (Herb.) Meerow is found above 4,000 meters. This species has adapted to high elevations by retaining the scape (and developing fruit) inside the bulb until the seeds are ripe.

Distinguishing characters (always present)

  • Bulbous herbs.
  • Leaves distichous, rarely spiral, simple; blades mostly linear or strap-shaped, the base often sheathing a short stem, sometimes pseudopetiolate.
  • Inflorescences umbels, borne on scapes.
  • Flowers with 6 tepals in 2 whorls, usually similar in shape and color; stamens 6; ovary inferior.
  • Fruits loculicidal capsules.

Other important characters

  • Seed testa with phytomelan crust.

Key differences from similar families

  • From Alliaceae s.s.: lack of allyl sulfide compounds, inferior ovary.
  • From Agapanthaceae: lack of steroid saponins, inferior ovary.
  • From Alliaceae s.s. and Agapanthaceae: presence of unique amaryllidaceous alkaloids.

Number of genera

In tropical America, there are 26 genera and about 375 species. The largest genera in the Neotropics are Hippeastrum (50-60 species), Hymenocallis (about 50), Zephyranthes (about 50), and Clinanthus (about 30).

NOTE: The genera Phycella Lindl., Rhodophiala C.Presl and Placea Miers have been excluded as they occur only in Mediterranean and temperate Chile and warm temperate Argentina.

  • Caliphruria Herb.
  • Chlidanthus Herb.
  • Clinanthus Herb.
  • Crinum L.
  • Eithea Ravenna
  • Eucharis Planch. & Linden
  • Eucrosia Ker Gawl.
  • Eustephia Cav.
  • Griffinia Ker Gawl.
  • Habranthus Herb.
  • Hieronymiella Pax.
  • Hippeastrum Herb.
  • Hymenocallis Salisb.
  • Ismene Salisb.
  • Leptochiton Sealy
  • Pamianthe Stapf
  • Paramongaia Velarde
  • Phaedranassa Herb.
  • Plagiolirion Baker
  • Pyrolirion Herb.
  • Rauhia Traub
  • Sprekelia Heist.
  • Stenomesson Herb.
  • Urceolina Rchb.
  • Worsleya Traub
  • Zephyranthes Herb.

Status

  • All of the genera listed except Crinum are endemic to the Americas.
  • In addition to the native species, there are several African Crinum species that are naturalized in the Neotropics.
  • Various other exotic members of the family are cultivated in the Neotropics, as are hybrids of native genera such as Hippeastrum.

Important literature

Baker, J.G. 1888. Handbook of the Amaryllideae. George Bell and Sons, London.

Herbert, W. 1837. Amaryllidaceae. J. Ridgeway and Sons, London.

Meerow, A.W. and D.A. Snijman. 1998. Amaryllidaceae. In: K. Kubitzki (ed.),  The Families and Genera of Vascular Plants 3: 83-110. Springer-Verlag, Berlin.

Meerow, A.W., M.F. Fay, C.L. Guy, Q-B. Li, F.Q. Zaman, & M.W. Chase. 1999.  Systematics of Amaryllidaceae based on cladistic analysis of plastid rbcL and trnL-F sequence data.  Amer. J. Bot. 86: 1325-45.

Meerow, AW., C.L. Guy, Q. Li, & S-L. Yang.  2000. Phylogeny of the American Amaryllidaceae based on nrDNA ITS sequences.  Syst. Bot. 25: 708-26.

Traub, H.P. 1963. Genera of the Amaryllidaceae. American Plant Life Society, La Jolla, CA.

How to cite

Meerow, A. (2009). Neotropical Amaryllidaceae. 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/Amaryllidaceae.htm.

Click images to enlarge


Habitat of Amaryllis belladonna (endemic to South Africa - this is naturalized) © John Wood, Darwin Initiative Project 161/11/026.



Flower of Amaryllis belladonna (endemic to South Africa - this is naturalized) © John Wood, Darwin Initiative Project 161/11/027.



Flowers of Clinanthus variegatus © Alan W. Meerow, USDA-ARS.



Habranthus sp. in Mairana, Bolivia © John Wood, Darwin Initiative Project 161/11/017.



Habranthus sp. in Mairana, Bolivia © John Wood, Darwin Initiative Project 161/11/015.



Flowers of Hieronymiella marginata vel sp. aff. © John Wood, Darwin Initiative Project 161/11/022.



Habitat of Hippeastrum parodii © John Wood, Darwin Initiative Project 161/11/028.



Inflorescence of Hippeastrum parodii © John Wood, Darwin Initiative Project 161/11/029.



Flowers of Hippeastrum parodii © John Wood, Darwin Initiative Project 161/11/030.



Habitat of Hippeastrum aviflorum © John Wood, Darwin Initiative Project 161/11/023.



Flower of Hippeastrum aviflorum © John Wood, Darwin Initiative Project 161/11/024.



Flower of Hippeastrum flammigerum © John Wood, Darwin Initiative Project 161/11/025.



Flower of Hippeastrum umabisanum © John Wood, Darwin Initiative Project 161/11/031.



Hymenocallis amancaes, flowers © Markus Ackermann, Freie Universität Berlin.



Flowers of Leptochiton quitoensis © Alan W. Meerow, USDA-ARS.



Phycella ignea in Chile © Alan W. Meerow, USDA-ARS.



Pucara leucantha, succulent leaves © Maximilian Weigend, Freie Universität Berlin.



Pucara leucantha, bulb, longitudinal section © Maximilian Weigend, Freie Universität Berlin.



Rhodophiala bagnoldii in coastal sands of Chile © Alan W. Meerow, USDA-ARS.



Rhodophiala bagnoldii in coastal sands of Chile © Alan W. Meerow, USDA-ARS.



Rhodophiala phycelloides in Chile © Alan W. Meerow, USDA-ARS.



Rhodophiala phycelloides in Chile © Alan W. Meerow, USDA-ARS.



Stenomeson aurantiacum, flowering group on dry stone wall © Maximilian Weigend, Freie Universität Berlin.



Flower of Zephyranthes sp. Bolivia © John Wood, Darwin Initiative Project 161/11/018.