Polygalaceae Explained

The Polygalaceae or the milkwort family are made up of flowering plants in the order Fabales. They have a near-cosmopolitan range, with about 27 genera and ca. 900 known species^[1] of herbs, shrubs and trees. Over half of the species are in one genus, Polygala, the milkworts.

The family was first described in 1809 by Johann Hoffmansegg and Johann Link.^[2] In 1896, Robert Chodat split it into 3 tribes. A fourth tribe was split off from the tribe Polygaleae in 1992.^[3] Under the Cronquist classification system, Polygalaceae were treated in a separate order of their own, Polygalales. Currently, according to the Angiosperm Phylogeny Group, the family belongs in Fabales.

Description

Polygalaceae are annual or perennial herbs, shrubs, trees or lianas. Its zygomorphic, hermaphrodite, bisexual flowers have 3-5 petals and 5 sepals.^[4] Its leaves are usually alternate, but may be opposite, fascicled, or verticillate. Each flower usually contains 8 stamens, though this may range from 3 to 10. They are usually in 2 series.^[4] The fruits of each plant can be a capsule, samara, or drupe.

Tribes and genera

The Polygalaceae comprise the following genera,^[5] with tribes based on various sources.^{[6] [7] [8] [9] [10] [11]}

• Carpolobieae Eriksen
  • Atroxima Stapf
  • Carpolobia G. Don
• Moutabeae Chodat
  • Barnhartia Gleason
  • Diclidanthera Mart.
  • Eriandra P. Royen & Steenis
  • Moutabea Aubl.
• Polygaleae Chodat
  • Acanthocladus Klotzsch ex Hassk.
  • Ancylotropis
  • Asemeia Raf.
  • Badiera DC.
  • Bredemeyera Willd.
  • Caamembeca J.F.B. Pastore
  • Comesperma Labill.
  • Epirixanthes Blume
  • Gymnospora (Chodat) J.F.B.Pastore
  • Hebecarpa (Chodat) J.R.Abbott
  • Heterosamara Kuntze
  • Hualania Phil.
  • Monnina Ruiz & Pav.
  • Monrosia Grondona
  • Muraltia DC.
  • Phlebotaenia Griseb.
  • Polygala L.
  • Polygaloides Haller
  • Rhamphopetalum J.F.B.Pastore & M.Mota
  • Rhinotropis (S.F. Blake) J.R. Abbott
  • Salomonia Lour.
  • Securidaca L.
• Xanthophylleae Chodat
  • Xanthophyllum Roxb.
• Tribe not assigned
  • Senega (DC.) Spach

Fossils

• †Deviacer Manchester
• †Paleosecuridaca Pigg, Kathleen B., M.L. DeVore & M.F. Wojc. 2008

Systematics

Modern molecular phylogenetics suggest the following relationships:^{[11] [12] [13] [14] [15] [16]}

Notes and References

1. Christenhusz, M. J. M. . Byng, J. W. . amp . 2016 . The number of known plants species in the world and its annual increase . Phytotaxa . 261 . 201–217 . 10.11646/phytotaxa.261.3.1 . 3 . free .
2. Web site: Harvard University . Royal Botanic Gardens Kew . Australian National Herbarium . Polygalaceae . International Plant Names Index . July 16, 2020.
3. Eriksen . Bente . Phylogeny of the Polygalaceae and its taxonomic implications . Plant Systematics and Evolution . 1993 . 186 . 1/2 . 33–55 . 10.1007/BF00937712 . 23674643 . 32590790 . 0378-2697.
4. Web site: Polygalaceae . Flora of Victoria . Government of Victoria, Australia . July 16, 2020.
5. Web site: Polygalaceae Hoffmanns. & Link . Plants of the World Online . Royal Botanic Gardens, Kew. 23 July 2024.
6. Abbott JR. . 2011 . Notes on the disintegration of Polygala (Polygalaceae), with four new genera for the flora of North America . Journal of the Botanical Research Institute of Texas . 5 . 1 . 125–137 . 41972495.
7. Pastore JFB. . 2012 . Caamembeca: Generic status and new name for Polygala subgenus Ligustrina (Polygalaceae) . . 67 . 3 . 435–442 . 10.1007/s12225-012-9360-x. 19252598 .
8. Pastore JF, Rodrigues de Moraes PL . 2013 . Generic status and lectotypifications for Gymnospora (Polygalaceae) . . 22 . 3 . 304–306 . 10.3417/2010113. 85269764 .
9. Abbott JR, Pastore JF . 2015 . Preliminary synopsis of the genus Hebecarpa (Polygalaceae) . . 70 . 3 . 39 . 10.1007/s12225-015-9589-2. 22601207 .
10. Ph.D. . Freire-Fierro A. . 2015 . Systematics of Monnina (Polygalaceae) . Drexel University . 2017-03-19 . https://web.archive.org/web/20170319195921/http://gradworks.umi.com/36/85/3685585.html . 2017-03-19 . dead .
11. Pastore JF, Abbott JR, Neubig KM, Whitten WM, Mascarenhas RB, Almeida Mota MC, van den Berg C . 2017 . A molecular phylogeny and taxonomic notes in Caamembeca (Polygalaceae) . . 42 . 1 . 54–62 . 10.1600/036364417X694935. 90353852 .
12. Persson C. . 2001 . Phylogenetic relationships in Polygalaceae based on plastid DNA sequences from the trnL–F region . . 50 . 3 (Golden Jubilee Part 5) . 763–779 . 10.2307/1223706 . 1223706.
13. Forest F, Chase MW, Persson C, Crane PR, Hawkins JA . 2007 . The role of biotic and abiotic factors in evolution of ant dispersal in the milkwort family (Polygalaceae) . . 61 . 7 . 1675–1694 . 10.1111/j.1558-5646.2007.00138.x. 17598748 . 37523521 .
14. Bello MA, Bruneau A, Forest F, Hawkins JA . 2009 . Elusive relationships within order Fabales: Phylogenetic analyses using matK and rbcL sequence data . . 34 . 1 . 102–114 . 10.1600/036364409787602348. 85655712 .
15. Ph.D. . Abbott JR. . 2009 . Phylogeny of the Polygalaceae and a revision of Badiera . University of Florida .
16. Mennes CB, Moerland MS, Rath M, Smets EF, Merckx VS . 2015 . Evolution of mycoheterotrophy in Polygalaceae: The case of Epirixanthes . . 102 . 4 . 598–608 . 10.3732/ajb.1400549. 25878092 . free .