Hydatella
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Hydatella is a genus of five species of minute aquatic herbs in the family Hydatellaceae found in Australia and New Zealand.
These diminutive, moss-like, aquatic plants are the closest living relatives of water-lilies and their allies. They reside near the point at which water-lilies (order Nymphaeales) diverged from other flowering plants. Only a single angiosperm species, Amborella trichopoda, diverged from other flowering plants below this point.[1]
Morphology places these plants near the base of the angiosperm clade. This position is supported by ten unequivocal synapomorphies
- lack of a vascular cambium,
- lack of pericyclic sclerenchyma,
- anomocytic stomata,
- truncate anther connective,
- boat-shaped pollen,
- inner integument with two cell layers,
- palisade exotesta,
- seed operculum formed by cell enlargement in the inner integument,
- perisperm and
- hypogeal germination. [2]
- Species
- Hydatella australis Diels
- Hydatella dioica D.A. Cooke
- Hydatella filamentosa (Rodway) W.M. Curtis (Thread Hydatella)
- Hydatella inconspicua (Cheesm.) Cheesm. (New Zealand Hydatella)
- Hydatella leptogyne Diels
[edit] References
- ^ Botany: New home for tiny aquatics, Else Marie Friis & Peter Crane, Nature 446, 269-270 (15 March 2007)
- ^ Hydatellaceae identified as a new branch near the base of the angiosperm phylogenetic tree. Jeffery M. Saarela1, et. al., Nature 446, 312-315 (15 March 2007)
