Royal Botanic Gardens, Kew, UK.
Perennial, rhizomatous herbs. Leaves: basal leaves 2-ranked, often equidistant, strongly ribbed, sometimes unifacial; scape with cauline leaves. Inflorescence a terminal raceme (solitary in Harperocallis McDaniel), elongating in fruit. Flowers subtended by a calyculus of 3 separate sepal-like scales; tepals 6, persistent, with prominent veins, fused below in a shallow cup or free; stamen filaments epitepalous, attached at top of tepalar cup, straight or narrowly subulate, flattened; anthers ± oblong, mucronulate, basifixed, latrorse; ovary superior, 3-locular, with numerous ovules; styles adherent to near apex, the apex usually truncate; stigmas capitate. Fruit septicidal or loculicidal capsules, body included by tepals, the style frequently exserted, the veins of each carpel usually developing into prominent ribs; carpels divided almost to base at dehiscence; seeds deep red, fusiform, surface reticulate and finely striate, with a white appendage on one end.
Notes on delimitation
- Tofieldiaceae have variously been included in the Nartheciaceae (Kubitzki 1998) and the Melanthiaceae (Dahlgren et al. 1985).
- The APG II recognizes it as its own family which is followed here.
Distribution in the Neotropics
A cosmopolitan family of 10 genera and c. 72 species. One genus comprising five species occurs in Latin America, while one monotypic genus is endemic to Florida, USA, just north of our floristic area.
- Harperocallis McDaniel: monospecific (H. flava McDaniel) is confined to western Florida, in the USA.
- Isidrogalvia Ruíz & Pav.: five species endemic to northwestern South America (Venezuela, Colombia, Ecuador and Peru).
Distinguishing characters (always present)
- Leaves strongly ribbed longitudinally.
- Racemose inflorescence.
- Undistinguished monocotyledoneous flowers.
Notable genera and distinguishing features
Isidrogalvia is the only representative in the Neotropics:
- Large strongly ribbed, persistent leaves with tomentose margins (glabrous in one species).
- The scapes bear several to numerous bracts, most are above the middle.
- The styles are united to their apices or nearly so and the seeds have an appendage that is decurrent along the seed body.
Harperocallis (from just outside our floristic area in Florida):
- As the circumscription of this family has been complicated, literature on family distinguishing features is scarce. Isidrogalvia has been included in Tofieldia Hudson in the past; Cruden (1991) discusses this and recognizes it as a separate genus.
Cruden, R.W. (1991). A revision of Isidrogalvia (Liliaceae): recognition for Ruiz and Pavón's Genus. Syst. Bot. 16:270-82.
Dahlgren, R.M.T., Clifford, H.T. and Yeo, P.F. 1985. The Families of the Monocotyledons. Springer-Verlag, Berlin.
Tamura, M.N. 1998. Nartheciaceae, pp. 381-392. In: Kubitzki, K. (ed.). The Families and Genera of Vascular Plants, vol. III. Springer-Verlag, Berlin.
How to cite
Haigh, A. (2009). Neotropical Tofieldiaceae. 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/Tofieldiaceae.htm.