Origin and Habitat: Atlantic Coast of Northeast and Southeast Brazil (Bahia, Rio de Janeiro, and Espírito Santo).
Altitude: 0-10 m asl.
Habitat: It grows in coastal strand or dry wood, just above the high tide mark directly on sometimes salty, white sandy soils, specially on isolated beaches or "dry restinga" biomes, and is widely cultivated as an ornamental. This species binds the Atlantic dunes with massive subterranean rhizomes near the southern limit of the tropics, just as Serenoa repensSN|24688]]SN|24688]] in the north America.

• Allagoptera arenaria (Gomes) Kuntze
• Cocos arenaria Gomes
• Diplothemium arenarium (Gomes) Vasc. & Franco

• Allagoptera arenaria (Gomes) Kuntze
• Cocos arenaria Gomes
• Diplothemium arenarium (Gomes) Vasc. & Franco
• Allagoptera pumila Nees
• Diplothemium littorale Mart.
• Diplothemium maritimum Mart.

Description: Allagoptera arenariaSN|24788]]SN|24788]], popularly known as seashore palm, is a small fruit palm usually less than 1,8 m tall. It is monoecious.
Trunk: Apparently acaulescent (stemless) to short-stemmed up to 1,5 m long and 10 cm in diameter, solitary (or bifurcately branched) but subterranean, rhizomatose, rarely visible, giving it the appearance of clustering, growing in a swirling pattern and spreading out on different and seemingly random planes. Occasionally some very old plants can have short stems well developed above the ground and can grow up to 2,4 m tall and 4,5 m wide.
Leaves: 6 to 15 dark green above, silver on the under surfasce, pinnately compound (spaced along both side of the flexible rachis ), spineless, arched, spreading right out of the ground from the subterranean trunk 50–180 cm long (usually less than 120 cm tall); leaflets about 50 on each side 40-60 cm long, with a prominent mid-rib, arranged in groups of 2-5 in several planes and curling to various degrees depending on plant, age and climate. Sheath not tubular, fibrous.
Inflorescence: Spicate, with stalk up to 90 cm long and spike up to 15 cm long, coming from the middle, both male and female with cream or pale yellow flower, so one plant can produce seeds by itself. The female flowers are borne in distinct spirals. Male flowers with 10-16 stamens. This species exhibits protandry, long-lasting, diurnal anthesis, and sweetly scented flowers and flowers usually attract bees and beetles.
Fruit: Small, ovoid to turbinate, about 25 mm long and 13 mm in diameter arranged in distinct spirals, yellowish green to orange getting dry soon, covered in brown tomentose scales, with long persistent flower parts and shaped like small coconuts.
Remarks: This is a tillering palm, it exhibits saxophone style root growth (it has a heel).

Bibliography: Major references
1) Jules Janick,Robert E. Paull The Encyclopaedia of Fruit & Nuts page 85
2) Maria Esmeralda S. Payão Demattê, International Society for Horticultural Science. Section for Ornamental Plants - 1994
3) The European Garden Flora Editorial Committee European Garden Flora: A Manual for the Identification of Plants Cultivated Page 75.
4) Andrew Henderson 2002 Evolution and ecology of palms - Pagina 121
5) Wikipedia, the free encyclopedia http://en.wikipedia.org/wiki/Allagoptera_arenaria [accessed 03-Jan-2013]
6) School of Biological Sciences University of Texas at Austin http://w3.biosci.utexas.edu/prc/Sabal/saxophone.html [accessed 03-Jan-2013]

Cultivation and Propagation: The seashore palm is cultivated in humid tropical, subtropical and warm-temperate regions and planted in gardens and parks. It is one of the best palms for beach and coastal situations in subtropical and tropical settings and can be planted just above the high tide mark. If you needs a small low maintenance, but graceful looking palm, it doesn't get any better than Allagoptera arenariaSN|24788]]SN|24788]] It is also very 'user friendly' with soft, leathery leaves and has not sharp edges or spines. However it considered an agonizingly slow-growing plant when it is young, at least when grown in a Mediterranean climate. But its growth will increase dramatically when placed in a greenhouse, or warm, humid climate and responds well to fertilizer and water. Once established, it is virtually maintenance-free.
Soil: It is very adaptable to many kinds of well drained soils. It prefers sandy soils with little mineral or organic content, but may also grow on poor and rocky soils and on peaty and poorly drained sites.
Fertilization: Need a perfect fertilizer diet including all micro nutrients and trace elements or slow release fertilizer applied during the growing season, or according to package directions, using a fertilizer specifically formulated for palms.
Water Requirements: It tolerates low levels of humidity and summer drought, though it prefers evenly moist but not consistently wet medium. When supplied with adequate moisture and fertilizer it is also fairly fast growing. This palm is very drought tolerant once established. It dislikes constantly soggy soils. This is one of the palms prone to get bud damage from overhead watering (drip much preferred) causing weird folded new leaves (leaflets bent back against themselves), particularly if not grown in full sun.
Light: Heliophilous (adapted for a high intensity of sunlight.) It prefers bright sunny locations, but it also does well in part shade with some direct sunlight. It will survive in rather heavy shade but "stretches" to lose its compact shape.
Aerosol salt tolerance: It is very tolerant of extreme coastal and beach exposure, as well as salt spray. This is one of the most salt tolerant palms!
Wind resistance: It endures drying winds.
Hardiness: USDA Zones (9)-10-11. Mature and established palms tolerates winter frosts down to about −4°C for short periods. A number of gardeners are now successfully growing the seashore palm in USDA Zone 9. Seashore palms grown in Zone 9 may require protection during cold spells.
Roots: Usually not a problem
Maintenance: For the healthiest and most attractive plant, keep the palm pruned. As the old fronds die, these should be trimmed off and the leaf bases allowed to dry out, but do not prune if the frond still has some green colour. Palms recycle nutrients from dead or dying fronds and use them for healthier fronds.
Uses: They are used massively in gardening and landscaping in many parts of the world with the silver form being especially attractive. Plant Allagoptera arenariaSN|24788]]SN|24788]] in front of clumps of larger palms, or even underneath large palms. They look good massed in clumps in mixed borders, or as framing hedges. They are also excellent in containers. And thanks to their drought resistance and durability to heat they can thrive in harsh urban conditions. They can be used for watershed protection, erosion control and as a beach screen.
Traditional uses: The leaves are used to make baskets and other woven objects.
Food uses: It is cultivated extensively in South America for the edible fruits which are eaten fresh or made into a drink or jam.
Propagation: In the nursery it may be propagated by seed. Seeds will germinate in 2 to 6 month. Seedling growth and early development are slow. The optimal germination conditions for seashore palm seeds include prolonged exposure to high temperatures from 32-38ºC and high humidity. Keep the seed moist at all times. Establishment requires not less than 2 to 6 years, but due to its slow growth rate, get one as large as possible when buying this species or you will be looking at a few green blades of grass for many years (even a decade) maybe. It can also be propagated through underground stools. A single old individual could have dozens of palms dominating large areas.