Elatinaceae

Waterwort Elatine triandra, copyright Stefan Lefnaer.

Belongs within: Malpighiales.

The Elatinaceae are a cosmopolitan group of herbs and shrubs found growing in or near water (Hickman 1993).

Characters (from Hickman 1993): Annual or perennial, in or near water; roots fibrous, from a tap root or not, generally from lower leaf axils as well. Stem generally soft. Leaves simple, opposite, more or less 4-ranked; stipules scarious. Inflorescence with flowers axillary or terminal, solitary or clustered. Flowers small, inconspicuous, radial, bisexual; sepals and petals generally free, 3-5, equal in number; ovary spheric, styles 3-5, very short. Fruit a capsule, septicidal, more or less spheric, ovoid, or depressed-ovoid, walls thin; chambers 2-5, each several- to many-seeded. Seed very small; surface net-like or glossy.

<==Elatinaceae [Elatineae] XR12
    |--Bergia XR12
    |    |--B. ammannioides H90
    |    |--B. occultipetala H90
    |    |--B. pedicellaris LK14
    |    |--B. perennis H90
    |    |    |--B. p. ssp. perennis H90
    |    |    `--B. p. ssp. obtusifolia H90
    |    |--B. polyantha VB02
    |    |--B. suffruticosa PP07
    |    |--E. texana XR12
    |    `--B. trimera H90
    `--Elatine Linnaeus 1753 A61
         |--E. ambigua H93
         |--E. americana (Pursh.) Arn. 1830 A61
         |--E. brachysperma [incl. E. obovata] H93
         |--E. californica H93
         |--E. chilensis [incl. E. gracilis] H93
         |--E. gratioloides Cunningham 1840 (see below for synonymy) A61
         |--E. heterandra H93
         |--E. minima V72
         |--E. rubella H93
         `--E. triandra WM09

Elatine gratioloides Cunningham 1840 [incl. E. americana Hook. f. 1852 non (Pursh.) Arn. 1830, E. americana var. australiensis Bentham 1863] A61

*Type species of generic name indicated

REFERENCES

[A61] Allan, H. H. 1961. Flora of New Zealand vol. 1. Indigenous Tracheophyta: Psilopsida, Lycopsida, Filicopsida, Gymnospermae, Dicotyledones. R. E. Owen, Government Printer: Wellington (New Zealand).

[H90] Harden, G. J. (ed.) 1990. Flora of New South Wales vol. 1. New South Wales University Press.

[H93] Hickman, J. C. (ed.) 1993. The Jepson Manual: Higher Plants of California. University of California Press: Berkeley (California).

[LK14] Lyons, M. N., G. J. Keighery, L. A. Gibson & T. Handasyde. 2014. Flora and vegetation communities of selected islands off the Kimberley coast of Western Australia. Records of the Western Australian Museum Supplement 81: 205–244.

[PP07] Pandey, R. P., & P. M. Padhye. 2007. Studies on phytodiversity of Arid Machia Safari Park-Kailana in Jodhpur (Rajasthan). Bulletin of the Botanical Survey of India 49: 15–78.

[VB02] Vijay, S. K., & T. N. Bhardwaja. 2002. Vegetation and phenodynamics of wetlands of central Rajasthan. Journal of the Bombay Natural History Society 99 (3): 573–581.

[V72] Voss, E. G. 1972. Michigan Flora. Part I. Gymnosperms and Monocots. Cranbrook Institute of Science and University of Michigan Herbarium.

[WM09] Wang, H., M. J. Moore, P. S. Soltis, C. D. Bell, S. F. Brockington, R. Alexandre, C. C. Davis, M. Latvis, S. R. Manchester & D. E. Soltis. 2009. Rosid radiation and the rapid rise of angiosperm-dominated forests. Proceedings of the National Academy of Sciences of the USA 106 (10): 3853–3858.

[XR12] Xi, Z., B. R. Ruhfel, H. Schaefer, A. M. Amorim, M. Sugumaran, K. J. Wurdack, P. K. Endress, M. L. Matthews, P. F. Stevens, S. Mathews & C. C. Davis. 2012. Phylogenomics and a posteriori data partitioning resolve the Cretaceous angiosperm radiation Malpighiales. Proceedings of the National Academy of Sciences of the USA 109 (43): 17519–17524.