Neotropical Alliaceae

Julie H. A. Dutilh

Universidade Estadual de Campinas (Unicamp), São Paulo, Brazil. 

Description

Perennial geophytes, with a bulb, rhizome or corm, often with alliaceous odour. Leaves concentrated basally, spirally arranged, often forming closed sheaths below, linear, filiform, flat, canaliculated, or terete, with parallel veins and internally with lacticifers. Inflorescence on a terete scape, usually umbel-like, with one to several flowers subtended by 1 (generally) or 2 or more membranous spathe bracts enveloping the immature inflorescence, generally free and spreading, but sometimes united at base, branches and pedicels sometimes also subtended with small bracts. Pedicels not articulate. Flowers hermaphrodite, usually actinomorphic, rarely zygomorphic to resembling an insect. Tepals usually 6, in two whorls apparent or not, rarely less, sometimes 3, with loss of inner ones, petaloid, united at base, rarely free, greenish, white, yellow, rose coloured or purple, rarely ornamented, sometimes with scales at the base of the tepals. Stamens usually 6, in two whorls, sometimes 3 staminodes and 3 fertile, or only 2 fertile. Filaments inserted on the base of the tepals, free or united at the base forming a tube around the ovary. Sometimes with scales or corona between the tepals or filaments. Ovary superior, tri-carpellate and tri-locular, 1- several ovules per locule, placentation axillary, nectaries septal with openings around the base of the style, or absent. Style at apex of ovary, solitary, erect, solid or sometimes partially hollow near the stigma. Stigma capitate, trilobate, rarely branched. Fruit loculicidal capsule, with 1- several seeds per locule. Seeds flat and dark to black due to phytomelan on the testa.

Notes on delimitation

  • The family Alliaceae, its genera and species have a complex taxonomic history, not yet fully understood.
  • The family Alliaceae is closely related to Amaryllidaceae and Agapanthaceae (entirely Old World), with which it is sometimes grouped into one large family. 
  • The family is divided in 3 subfamilies: Allioideae, Tulbaghioideae and Gilliesioideae, this last one comprising all South American genera.

Distribution in the Neotropics

Genera from South America:

  • Gilliesia Lindl.: Two species in Chile.
  • Ipheion Raf.: Genus with 3 species in Central Chile, Argentina, Uruguay and South Brazil.
  • Leucocoryne Lindl. Fifteen species in Chile.
  • Miersia Lindl.: Bolivia and Chile.
  • Nothoscordum Kunth: This is the biggest genus of the family in South America with about 30 species found in Argentina, Uruguay, Paraguay, Chile, Bolivia, Peru, and Brazil.
  • Schickendantziella Speg.: Monotypic genus from Tucumán, Argentina.
  • Speea Loes.: Two species in Chile.
  • Solaria Phil.: Five species in South Chile and South Argentina.
  • Tristagma Poeppig: Genus with about 14 species in Chile and Argentina.
  • Trichlora Baker.: Two species in Peru.

Key differences from similar families

Number of genera

  • 10 Neotropical genera (see list above).

Useful tips for generic identification

  • Gilliesia Lindl.: plants with 1-2  leaves linear, flat. Inflorescence with 2-9 flowers, spathe bracts 2. Flowers bilaterally symmetric, green or purple, sometimes resembling an insect with wings and legs, tepals 6 or rarely 5, free, unequal, with appendages, inner surface with thick epidermis with papillate cells. Stamens 3 fertile, 3 staminodes on a synandrium. Corona of irregular scales on the outside of the staminal cup. Style trilobed.
  • Ipheion Raf.: plants sometimes with alliaceous odour. Scape geotropic, decumbent at end of flowering, spathe bracts 2 united for less more than ¾ at one margin and about 1/3 on the other. Flower generally one, actinomorphic, yellow, tepals united at lower 1/3 to ½, filaments free from each other, much longer than the tepal tube, adnate to the perigone in two series, no corona or scales, stigma small capitate. Testa of seeds pitted.
  • Leucocoryne Lindl. plants sometimes with alliaceous odour. Scape erect with 1- 12 flowers, spathe bracts linear lanceolate, flower actinomorphic, 6 tepals, isomorphic, united at the base in a conspicuous tube, stamens 3 or 6 fertile, when 3 then opposite the outer tepals, the staminodes long, protruding from the throat. Style short, stigma capitate.
  • Miersia Lindl.: inflorescence 3- 7 flowered. Flowers bilaterally symmetric, green with purple lines, with 6 tepals in two series, free, acuminate, with appendages with papillate cells, anthers 6, small, fused in a staminal cup, corona of 6 narrow scales outside, style abaxially reflexed, stigma disk like.
  • Nothoscordum Kunth: plants sometimes with alliaceous odour. Scape erect, spathe bracts 2 or rarely more, free or united for less than 1/4. Flowers actinomorphic, mostly white, sometimes with purplish lines, or yellow. Tepals 6 united for less than 1/3, anthers adnate to the tepal tube in one series, no corona or scales, filaments may be united basally, ovary sometimes with small gynophore, stigma small capitate, ovules 1- several per locule, testa of seed smooth. Nothoscordum fictile Macbride and N. sessile Beauverd from NW Argentina differ from all other Alliaceae in South America by having pedicels with individual bracts and by the apiculate outer tepals. These bracts also appear in N. andinum Fuentes, a species sometimes considered as genus Zoellnerallium Crosa.
  • Schickendantziella Speg.: inflorescence with 1-2 flowers, flowers actinomorphic, nodding, tepals 3, almost free, caudate, pinkish-brown with purple, anthers 6, filaments connate, enveloping the ovary, no corona or scales. Ovary with many ovules. 
  • Speea Loes.: inflorescence 1-3 flowered with 1-2 spathe bracts separate from each other, the outer may form a tube below, flowers pinkish brown with purple, tepals 6, free, caudate, no corona or scales. Anthers basifixed.
  • Solaria Phil.: inflorescence short scape with 3-15 flowers, spathe bracts 2. Flowers bilaterally symmetric, green, tepals 6, united. Outer median tepal distinctly larger than the others, giving a labellum like effect, and the inner median tepal often smaller than the two lateral ones. Fertile stamens 1-5, basally connate, staminodes 3 or absent, corona of small scales or absent. Stigma capitate.
  • Tristagma Poeppig: plants may have alliaceous odour. Inflorescence scape erect, flowers 1-several, spathe bracts united for less than 1/6, tepals 6 united in a tube for ¼ to 3/5 , anthers 6 included in the tepal tube, filaments absent to long, free from each other, bases partially adnate to the perigone forming small cups, no corona or scales, testa of seeds smooth.
  • Trichlora Baker.: bulb tunicated, narrow. Inflorescence with about 5 flowers, spathe bracts 2 free from each other. Flowers actinomorphic, with outer tepals lanceolate, green, free, inner short, obtuse, scale like, green. Stamens 3 fertile, 3 staminodes, corona absent. Stigma with 3 hornlike branches.

Notable genera and distinguishing features

See above.

Status

  • Native, and some introduced species.

General notes

  • The genus Allium L., from the Northern hemisphere i.e. Asia, Europe and North America, has several edible species widely cultivated that may sometimes appear as spontaneous. They can be distinguished mainly by their gynobasic style, i.e. base of style sunken in the middle of the ovary, and by the opening of the nectaries at the base of the ovary.
  • Some species from different genera are also cultivated as ornamentals.

Important literature

Fay, M.F., & Chase, M.W. 1996. Ressurection of  Themidaceae for the "{Brodiaea}" alliance, and recircumscription of Alliaceae, Amaryllidaceae and Agapanthoideae. Taxon 45: 441-451.

Fay, M.F., Rudall , P.J. & Chase, M.W. 2006. Molecular studies of subfamily Gilliesioideae (Alliaceae). Aliso 22: 367-371.

Guaglianone, R. 1972. Sinopsis de Las especies de Ipheion Raf. y Nothoscordum Kunth (Liliáceaes) de Entre Rios y Regiones Vecinas. Darwiniana 17: 159-240.

Rahn, K. 1998. Alliaceae. In: Kubitzki, K. (ed.) The Families and Genera of Vascular Plants, Monocotyledons - Lilianae (except Orchidaceae) 3:70-78.  Springer-Verlag, Berlin.

Rudall , P.J.,  Bateman, R.M., Fay, M.F. & Eastman, A. 2002. Floral anatomy and systematics of Alliaceae with particular reference to Gilliesia, a presumed insect mimic with strongly zygomorphic flowers. Amer. J. Bot. 81(12): 1867-1883.

How to cite

Dutilh, J.H.A. (2009). Neotropical Alliaceae. 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/Alliaceae.htm.