|A. distachyos, foliage and|
inflorescence at water surface
The Aponogetonaceae (Cape-pondweed family or Aponogeton family) are a family of flowering plants in the order Alismatales. The Aponogetonaceae is considered to be allied to the Potamogetonaceae - Najadaceae complex of families.
In recent decades the family has had universal recognition by taxonomists. The APG system (1998) and APG II system (2003) treat it in the order Alismatales in the clade monocots. The family consists of only one genus, Aponogeton, with 56 known species (Christenhusz & Byng 2016 ) of aquatic plants, most of which have been included in a molecular phylogeny by Chen et al. (2015). The name was published in Supplementum Plantarum 32: 214 (1782) and is derived from a geographic location neighboring (geton) the Apono tribal district of coastal Gabon. Some species are used as ornamental plants in aquariums.
Individual plants are not always easy to identify due to hybridization (particularly those sold as A. crispus - which are often cultivated hybrids with A. natans or A. rigidifolius).
Generally an Aponogeton from Asia will have a single bloom stalk, while those from African heritage (including Madagascar) will have multiple blooming stems on the same flower stalk.
Even though 17 species are found in Africa, only one of them, A. distachyos, has been continuously maintained as a plant in garden ponds. Several of the 11 Madagascan species have been introduced as new aquarium plants in the early 21st century. At present, the following plants from Madagascar are in culture: Aponogeton boivinianus, A. longiplumulosus, A. madagascariensis and A. ulvaceus. Additionally, Aponogeton bernierianus, A. capuronii, A. decaryi and A. tenuispicatus have been imported on several occasions but have not achieved any wider distribution because they are difficult to maintain. From the 16 representatives of this genus from Asia and Australia, A. crispus, A. elongatus, A. rigidifolius, A. robinsonii and A. undulatus are useful aquarium plants. Aponogeton jacobensii, A. natans and A. loriae, too, were cultivated several times but have not proven themselves under aquarium conditions.
Many species grow in temporarily still or flowing waters and live through the dry period as a dormant tuber. They are fully aquatic herbaceous plants with milky sap, becoming dormant during drought conditions. Most species grow from tubers. Most Asian species remain submerged all year round, while the starchy tubercles of the African species are able to survive the dry season by shedding their leaves and undergoing a dormant period.
Almost all Aponogeton species go through resting and growth phases in their natural locations, triggered by the local ecological conditions. During growth periods, the plant will deposit proteins, fats, carbohydrates and mineral substances in the storage rhizome or tuber During the resting period, the tuber survives in the soil in order to again sprout during the following vegetation period. Tubers in Aponogeton species have a high resistance to drying out. This ability to store water is exploited, for instance, in the annual export of thousands of dormant A. crispus specimens, shipped in large bags in a totally dry state.
The tubers of several species are eaten by humans and their livestock. Some are grown as ornamental plants in aquariums or ponds. The 1889 book 'The Useful Native Plants of Australia records that "The tuberous roots of these water-plants are starchy, and of excellent taste, though not large".
All Aponogeton species are easy to grow when their preferences are met. The Madagascar lace plants (A. madagascarensis) require special handling as they prefer cooler water – 70 °F (21 °C) as a maximum. As of 2010, the Australian species exist in very small numbers in the hobby trade.
The African species in particular, (with the exception of A. rigidifolius, which has a rhizome and not a tuber, experience a natural rest period, corresponding to their habitat drying out in the wild. The Asian species may also have a rest period, but this is related only to temperature. As the plant stops growing, it can be taken out of the pond or aquarium and put in a bowl of damp sand. Keep the bowl in a dark, cool place, with the sand kept damp, for approximately 2–3 months at a temperature of about 50–64 °F (10–18 °C), until small leaves are seen to sprout from the tuber, when they can be returned to the pond or aquarium.
- Aponogeton abyssinicus Hochst. ex A. Rich.
- Aponogeton afroviolaceus Lye
- Aponogeton angustifolius Ait.
- Aponogeton azureus H. Bruggen
- Aponogeton bernierianus (Decne.) Hook.
- Aponogeton boivinianus Baill. ex Jum.
- Aponogeton bogneri H. Bruggen
- Aponogeton bullosus H.Bruggen
- Aponogeton capuronii H. Bruggen
- Aponogeton crispus Thunb.
- Aponogeton desertorum Zeyh. ex A. Spreng.
- Aponogeton distachyos L.f.
- Aponogeton elongatus F. Muell. ex Benth.
- Aponogeton euryspermus Hellq. & S.W.L.Jacobs
- Aponogeton fotianus J. Raynal
- Aponogeton junceus Lehm.
- Aponogeton lakhonensis A. Camus (1909)
- Aponogeton longiplumulosus H. Bruggen (1968)
- Aponogeton madagascariensis (Mirb.) H. Bruggen
- Aponogeton natalensis Oliv.
- Aponogeton natans (L.) Engl. & K. Krause
- Aponogeton nudiflorus Peter.
- Aponogeton ranunculiflorus Jacot Guill. & Marais
- Aponogeton rehmannii Oliv.
- Aponogeton rigidifolius H. Bruggen
- Aponogeton stuhlmannii Engl.
- Aponogeton subconjugatus Schumach. & Thonn.
- Aponogeton troupinii J. Raynal
- Aponogeton ulvaceus Bak.
- Aponogeton undulatus Roxb.
- Aponogeton vallisnerioides Baker
- Aponogeton satarensis
- Angiosperm Phylogeny Group (2009), "An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG III", Botanical Journal of the Linnean Society, 161 (2): 105–121, doi:10.1111/j.1095-8339.2009.00996.x, archived from the original on 2018-03-30
- van Bruggen, H. W. E. (1985). "Monograph of the genus Aponogeton (Aponogetonaceae)". Bibliotheca Botanica. Stuttgart: E. Schweizerbart'sche Verlagsbuchhandlung. 33 (137): i–viii, 1–76. ISBN 978-3-510-48008-1. ISSN 0067-7892. Retrieved 2010-03-13.
- Christenhusz, M. J. M. & Byng, J. W. (2016). "The number of known plants species in the world and its annual increase". Phytotaxa. Magnolia Press. 261 (3): 201–217. doi:10.11646/phytotaxa.261.3.1.
- Punu (Apono)
- Watson, L. & Dallwitz, M. J. (1992 onwards): Aponogetonaceae Archived April 24, 2006, at the Wayback Machine
- J. H. Maiden (1889). The useful native plants of Australia : Including Tasmania. Turner and Henderson, Sydney.
- Gesting, B. Nature and Aquarium
- African Flowering Plants Database: Aponogeton
- Huxley, A., ed. (1992). New RHS Dictionary of Gardening. Macmillan ISBN 0-333-47494-5.
- Govaerts, R. et al. (2019) Plants of the world online: Aponogeton. Board of Trustees of the Royal Botanic Gardens, Kew. Retrieved 20 March 2019.
- Chen, L-Y.; Grimm, G. W.; Wang, Q-F.; Renner, S. S. (2015). "A phylogeny and biogeographic analysis for the Cape-Pondweed family Aponogetonaceae (Alismatales)". Molecular Phylogenetics and Evolution. 82: 111–117. doi:10.1016/j.ympev.2014.10.007. PMID 25462997.
- Illustrated Success with easy-growing Aponogeton plants
- Aponogeton Family by Karen Randall
- Aponogetons by Karen Randall
- Aponogetonaceae in L. Watson and M.J. Dallwitz (1992 onwards). The families of flowering plants: descriptions, illustrations, identification, information retrieval. Version: 9 March 2006. https://web.archive.org/web/20070103200438/http://delta-intkey.com/
- Monocot families (USDA)
- Aponogetonaceae in the Flora of North America
- NCBI Taxonomy Browser
- links at CSDL, Texas
- Les, Donald H.; Moody, Michael L.; Jacobs, Surrey W. L. (2005). "Phylogeny and Systematics of Aponogeton (Aponogetonaceae): The Australian Species". Systematic Botany. 30 (3): 503–519. doi:10.1600/0363644054782215. ISSN 0363-6445. PDF