Neotropical Ranunculaceae

Cassia Mônica Sakuragui

Universidade Federal do Rio de Janeiro, R.J. Brazil.

Description

Annual to perennial herbs, shrubs or lianas (Clematis); plants hermaphrodite or dioeciousLeaves alternate (often) or opposite (Clematis), simple or compound, margins entire, crenate, serrate or dentate; petiolate; stipules absent.  Inflorescences: flowers solitary or of cymes, racemes or panicles, terminal or axillaryFlowers actinomorphic or zygomorphic, whorled, partially whorled or spiral; calyx polysepalous or partially gamosepalous, the sepals (3-)5-8, often petaloid; corolla polypetalous, partially gamopetalous or gamopetalous, the petals 0-50,  imbricate, clawed, sessile, various colors; androecium with many free stamens, maturing centripetally, free from the perianth, 1-13 whorled or spiralled, the anthers adnate, dehiscing via longitudinal slits or longitudinal valves; gynoecium superior, apocarpous (1-)3-100-many carpelled, carpels non-stylate or stylate, ovules 2-many, placentation marginal or basalFruit follicles or achenes, dry or fleshy (rarely), aggregated (usually) or single, dehiscent or indehiscent.

Notes on delimitation

  • A well-defined family resolved within the Ranunculales.  The family is considered as one of the most basal families within the eudicots. The family shows a wide range of morphological characters, especially in fruit types and floral organization.  Several classifications have been proposed for Ranunculaceae based on morphological characters (Tamura, 1995), on molecular data (Ro & al., 1997), and on a combined molecular and morphological dataset (Wang & al. 2009).
  • The family was subdivided into three subfamilies and eleven tribes by Tamura (1993, 1995). This classification has been based on chromosome base number, carpel and fruit types. Phylogenetic analyses resolve the family as sister to the Menispermaceae and Berberidaceae.

Distribution in the Neotropics

  • Although Ranunculaceae species are distributed worldwide (Wang et al., 2009), its members are most common in the temperate and cold areas of the northern hemisphere. The diversity is reduced in the tropics: of nearly 62 genera in total, only 11-13 are native to the Neotropics, with 90-100 species in total.

11-13 native genera:

  • Aphanostemma St-Hil. - 1 sp., low elevation, southern Brazil to central Argentina.
  • Anemone L. - 5 spp., almost cosmopolitan; in Latin America in temperate areas and zones of high elevation.
  • Barneoudia Gay - 3 spp., endemic to high elevation in Chile and Argentina.
  • Callianthemoides Tamura - 1 spp., endemic to high elevation in Chile and Argentina.
  • Caltha L. - 3 spp., cold, humid zones of the world; the 3 species in the high Andes and southern South America.
  • Clematis L. - c. 15 spp., throughout Latin America, mostly temperate and subtropical.
  • Hamadryas Comm. ex Juss. - 6 spp., limited to high elevation in Chile and Argentina.
  • Krapfia DC.  - 8 spp., confined to high elevation in the Andes.
  • Laccopetalum Ulbr. - 1 spp., confined to high elevation in the Andes.
  • Myosurus L. -  2(?3) spp., Laurasia, Mexico, and soouthern South America.
  • Oreithales Schldl. - 1 spp., endemic to the high elevation in Bolivia and Peru.
  • Ranunculus L. - 40-50 spp., almost cosmopolitan; in Latin America in areas with high humidity.
  • Thalictrum All.  - 10 spp., Mexico through Central America and the Andes to southern Argentina.

4 introduced genera:

  • Actaea L.
  • Aquilegia L.
  • Consolida Gray
  • Delphinium L.

Distinguishing characters (always present)

Other important characters

  • Habit: herbs, shrubs or lianas (Clematis).
  • Leaves: alternate (often), or opposite (Clematis).
  • Fruits: achenes, follicles, or berries.

Useful tips for generic identification

  • Aconitum - sepals and petals present, petals hidden by the sepals.
  • Anemone - perianth without distinction between sepals and petals, with styles; achenes without veins on lateral surface.
  • Aphanostemma - ovary with one ovule. Barneoudia - absence of basal leaves at flowering (See Meyer et al. 2010 for more details).
  • Caltha - perianth without distinction between sepals and petals, all sepaloid; follicles.
  • Clematis - liana, while all other genera are herbs or shrubs.
  • Hamadryas - unisexual flowers, while all other genera have bisexual flowers. Myosurus - ovary with one ovule.
  • Oreithales - absence of involucral bracts on the inflorescence (See Meyer et al. 2010 for more details).
  • Ranunculus - petals and sepals present, sepals 3-6, petals with basal nectaries.

Status

  • 11-13 native genera; 4 introduced and cultivated.

General notes

  • Ornamental plants.
  • Many taxa within the family are pharmaceutically important and some have confirmed medicinal value.
  • Plants belonging to the Ranunculaceae have complex chemical compositions, many of which represent important taxonomic characteristics and the same chemical constituents are shared among different genera (Peng et al., 2006).

Important literature

APG II. 2003.  An Update of the Angiosperm Phylogeny Group Classification for the orders and families of flowering plants: APG II. Botanical Journal of the Linnean Society 141: 399-436.

Cronquist, A. 1981.  The families and genera of flowering plants. Columbia University Press, New York.

Lourteig, A. 1951.  Ranunculaceas de Sudamérica templada. Darwiniana 9: 562-604.

Lourteig, A. 1956.  Ranunculaceas de Sudamérica tropical. Memoria de la Sociedad de Ciencias Naturales La Salle 16: 199-224.

Meyer, K.M., Hot, S.B., & Arroyo, M.T.K. 2010.  Phylogenetic Affinities of South American Anemone (Ranunculaceae) including the endemic segregate genera Barnoudia and Oreithales. Int. J. Plant Sci. 171 (3): 323-331.

Peng Y., Chen S.B., Chen, S.L. & Xiao, P.G. 2006.  Preliminary pharmaphylogenetic study on Ranunculaceae, China.  J. Chin. Materia Medica 31: 1124-1128.

Ro, K., Keener, C.S. & McPheron, B.A. 1997.  Molecular phylogenetic studies of the Ranunculaceae: Utility of the nuclear 26S ribosomal DNA in inferring intrafamiliar relationships. Molec. Phylog. Evol. 8: 117-127.

Tamura, M. 1993.  Ranunculaceae. In: K. Kubitzki, J.G. Rohwer & V. Bittrich (eds.). The Families and Genera of Vascular Plants vol. 2, pp. 563-583. Springer-Verlag, Berlin.

Tamura, M. 1995.  Angiospermae. Ordnung Ranunculales. Fam. Ranunculaceae. II. Systematic Part. In: Hiepko, P. (ed.), Die natürliche Pflanzenfamilien, ed. 2, 17aIV, pp. 223-519. Duncker & Humblot, Berlin.

Ziman, S.N. & Keener, C.S. 1989.  A geographical analysis of the family Ranunculaceae. Ann. Missouri Bot. Gard. 76: 1012-1049.

Wang, W., Lu, A.-M., Ren, Y., Endress, M.E. & Chen, Z.-D. 2009. Phylogeny and classification of Ranunculales: Evidence from four molecular loci and morphological data. Perspect. Pl. Ecol. Evol.Syst. 11: 81-110.

How to cite

Sakuragui, C.M. (2011). Neotropical Ranunculaceae. 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/Ranunculaceae.htm.