1. Geraniaceae Juss.

    1. This family is accepted.

[NTK]

Aedo, C. (2009). Neotropical Geraniaceae.

Morphology
Description

Herbs, annual or perennial , rarely shrublets. Leaves alternate or opposite, palmate or pinnate divided , petiolate ; stipules present. Flowers in cymes or pseudoumbels, bisexual , usually actinomorphic . Sepals 5, usually distinct, imbricate . Petals 5, distinct. Fertile stamens 5 or 10, usually in 2 whorls, sometimes a whorl reduced to staminodes; anthers 2-locular, longitudinal dehiscent . Ovary superior ; carpels 5, connate ; ovules 1 or 2 per locule , pendulous, anatropous. Fruit a schizocarp with 5 1-seeded awned mericarps which separate elastically from a central beak. Seeds usually with little or no endosperm ; embryo folded.

General Description
Notes on delimitation
  • Hypseocharis Remy is a genus endemic to the Andes (from Argentina to South Peru) which was traditionally classified as Oxalidaceae. Molecular data suggest that it is the sister group of the true Geraniaceae. Thus, APG II included it as a part of Geraniaceae.
  • Hypseocharis differs from the Geraniaceae in its capsular fruit, estipulate leaves, 12 ovules per locule and its cochlear embryo with spirally folded cotyledons. These important features indicate that Takhtajan's (1996) view considering the genus as an independent family of Geraniales is more congruent with all available evidence. 
  • The genera Balbisia Cav. and Rhynchotheca Ruiz & Pav. are sometimes included within Geraniaceae s.l., but here they form their own family; the Ledocarpaceae.
Number of genera
  • 2 genera: Geranium and Erodium
Status
  • Geranium (native), Erodium (naturalized).
General notes
  • In Geranium the inflorescence is a cyme sometimes reduced to 1-flowered cymules born on a reduced stem, or more commonly composed of 2-flowered cymules alongated stem. In some cases these cymules are grouped in pseudoumbel aggregates towards the end of the branches.
  • In Erodium inflorescences are composed of pseudoumbels at the end of each branch.
  • All Neotropical Geranium species have 10 fertile stamens. Erodium has 5 fertile stamens (alternate with the petals) and 5 staminodes (opposite the petals).
Distribution
Distribution in the Neotropics
  • Geranium L. has many native species and some naturalized in the Neotropical area.
  • It is present in most important mountains of Tropical America, and some dry areas near the sea, although it is absent in lowland tropical forest.
  • Erodium L'Hér. is a weed with some species naturalized in disturbed mountain areas.
Diagnostic
Distinguishing characters (always present)
  • Flowers have 5 sepals and 5 petals.
  • The whole family has a fruit in a schizocarp with five awned mericarps.
Useful tips for generic identification
  • Number of stamens 10 in Geranium  and 5 in Erodium .
  • Leaf venation usually palmate in Geranium and pinnate in Erodium .
Literature
Important literature

Aedo, C. 2001. Taxonomic revision of Geranium sect. Brasiliensia (Geraniaceae). Syst. Bot. 26(2): 205-215.

Aedo, C., Aldasoro, J.J. & Navarro, C. 2002. Revision of Geranium sections Azorelloida, Neoandina and Paramensia (Geraniaceae). Blumea 47: 205-297.

Aedo, C., Aldasoro, J.J., Sáez, L. & Navarro, C. 2003. Taxonomic revision of Geranium sect. Gracilia (Geraniaceae). Brittonia 55: 93-126.

Aedo, C.,  Navarro, C. & Alarcón, M.L. 2005. Taxonomic revision of Geranium sections Andina and Chilensia (Geraniaceae). Bot. J. Linn. Soc. 149: 1-68.

Moore, H.E. 1943. A revision of the genus Geranium in Mexico and Central America. Contributions from the Gray Herbarium of Harvard University 146: 1-108, 5 "Plate".

http://www.rjb.csic.es/Geranium/index_geranium.php    This web page provides descriptions, nomenclature, drawings, photographs and references about many Geranium species of the Neotropics.

[FZ]

Geraniaceae, T. Müller. Flora Zambesiaca 2:1. 1963

Habit
Herbs, shrubs or suffrutices, very rarely arborescent
Leaves
Leaves alternate or opposite, if opposite often unequal, usually stipulate and petiolate, serrate, crenate or dentate, lobed or dissected or compound, rarely entire
Inflorescences
Inflorescence usually axillary, sometimes pseudumbellate (rarely 1-flowered)
Flowers
Flowers bisexual (or very rarely dioecious), actinomorphic or zygomorphic, hypogynous, 5 (rarely 4 or 8)-merous
Calyx
Sepals persistent, free or connate at the base, usually imbricate, the posterior one sometimes spurred
Corolla
Petals free, usually imbricate, occasionally 4, 2 or 0 by reduction
Nectaries
Disk (or extrastaminal) glands often present
Androecium
Stamens usually obdiplostemonous, twice as many as the sepals, more rarely 3 times as many (some sometimes sterile); filaments usually 4: connate at the base, sometimes in 5 bundles of 3 each; anthers 2-thecous, dehiscing longitudinally, introrse
Gynoecium
Ovary superior, syncarpous, 3–5 (rarely 2 or 8)-locular, usually lobed, usually rostrate (always in our area); style present or absent; stigmas ligulate, clavate or filiform, rarely capitate; loculi 1–2 ovulate; ovules pendulous, anatropous, superposed, placentation axile
Fruits
Fruit a schizocarp or sometimes a 3–5 (rarely 8)-lobed capsule; lobes or mericarps usually 1-seeded and dehiscing septicidally; mericarps (cocci) rostrate, breaking away from a persistent central column
Seeds
Seeds smooth or minutely reticulate; embryo curved, rarely straight; endosperm scanty or absent
[FWTA]

Geraniaceae, Hutchinson and Dalziel. Flora of West Tropical Africa 1:1. 1954

Habit
Annual herbs or undershrubs, rarely arborescent; leaves alternate or opposite, mostly lobate, dissected or compound; stipules often paired
Flowers
Flowers often handsome, hermaphrodite, actinomorphic or slightly zygomorphic, axillary, solitary to subumbellate
Calyx
Sepals persistent, 4–5, free or connate to the middle, imbricate or rarely valvate, the dorsal one sometimes spurred
Corolla
Petals 5, rarely 4, very rarely absent, hypogynous or subperigynous, imbricate, rarely contorted
Androecium
Stamens 2–3 times the number of the sepals, sometimes a few without anthers; filaments mostly more or less connate at the base; anthers 2-celled, opening lengthwise
Gynoecium
Ovary 3–5-lobed; ovules 1–2 in each cell, superposed, pendulous, rarely more than 2
Fruits
Fruit lobed; lobes 1-seeded, rarely more-seeded, often beaked, opening from the base upwards
Seeds
Seeds pendulous, with thin or no (rarely copious) endosperm and mostly curved or folded embryo
[FTEA]

Geraniaceae, J. O. Kokwaro (University College Nairobi). Flora of Tropical East Africa. 1971

Habit
Herbs, shrubs, or suffrutices, very rarely arborescent; stems fleshy
Leaves
Leaves alternate or opposite, radical ones occasionally in basal rosettes, if opposite often unequal, usually stipulate and petiolate, serrate, crenate or dentate, lobed, dissected or compound, rarely entire
Inflorescences
Inflorescence usually axillary, sometimes pseudumbellate, occasionally l-flowered, determinate, bracteate
Flowers
Flowers hermaphrodite or very rarely dioecious, usually chasmogamous but occasionally cleistogamous, actinomorphic or zygomorphic, hypogynous, generally (4)5(8)-merous, heterochlamydous
Calyx
Sepals (4)5, free or connate at the base, imbricate or rarely valvate, the posterior (uppermost) one sometimes spurred (especially in Pelargonium)
Corolla
Petals 5 (rarely 8, 4, 2, or even 0 by reduction), free, mostly unequal, hypogynous or subperigynous, imbricate or rarely contorted
Nectaries
Disk (extrastaminal or nectariferous) glands often present, alternating with the petals
Androecium
Stamens twice as many as the sepals, more rarely three times as many, some occasionally sterile; filaments free, usually ± connate at the base, sometimes connate in 5 bundles of 3 each; anthers versatile, introrse, 2-thecous, dehiscing longitudinally; pollen grains of different types, usually 3-colpate or 3-colporate
Gynoecium
Ovary superior, syncarpous, (2)3-5(8)-locular; ovules 1-2 in each chamber, pendulous, anatropous, superposed; placentation axile; style present and adhering to the beak or absent; stigmas ligulate, clavate or filiform, rarely capitate
Fruits
Fruit a schizocarp or sometimes a 3-5(rarely 8)-lobed capsule; mericarps rostrate, breaking away from a persisting central column, usually 1-seeded (rarely 2-many-seeded) and dehiscing septicidally
Seeds
Seeds smooth or minutely reticulate; embryo curved, rarely straight; endosperm scanty or absent

Images

Geraniaceae Juss. appears in other Kew resources:

First published in Gen. Pl. [Jussieu] 268. 1789 [4 Aug 1789] (1789)

Accepted by

  • APG IV (2016) http://dx.doi.org/10.1111/boj.12385

Sources

Flora Zambesiaca
Flora Zambesiaca
http://creativecommons.org/licenses/by-nc-sa/3.0

Flora of Tropical East Africa
Flora of Tropical East Africa
http://creativecommons.org/licenses/by-nc-sa/3.0

Flora of West Tropical Africa
Flora of West Tropical Africa
http://creativecommons.org/licenses/by-nc-sa/3.0

Kew Names and Taxonomic Backbone
The International Plant Names Index and World Checklist of Selected Plant Families 2018. Published on the Internet at http://www.ipni.org and http://apps.kew.org/wcsp/
© Copyright 2017 International Plant Names Index and World Checklist of Selected Plant Families. http://creativecommons.org/licenses/by/3.0

Neotropikey
Milliken, W., Klitgard, B. and Baracat, A. (2009 onwards), Neotropikey - Interactive key and information resources for flowering plants of the Neotropics.
http://creativecommons.org/licenses/by/3.0