''Eugeissona'' is a clustering

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...

in the palm family native to

Borneo Borneo (; id, Kalimantan) is the third-largest island in the world and the largest in Asia. At the geographic centre of Maritime Southeast Asia, in relation to major Indonesian islands, it is located north of Java, west of Sulawesi, and eas ...

Thailand Thailand ( ), historically known as Siam () and officially the Kingdom of Thailand, is a country in Southeast Asia, located at the centre of the Indochinese Peninsula, spanning , with a population of almost 70 million. The country is bo ...

and

Malaysia Malaysia ( ; ) is a country in Southeast Asia. The federation, federal constitutional monarchy consists of States and federal territories of Malaysia, thirteen states and three federal territories, separated by the South China Sea into two r ...

. The six

monoecious Monoecy (; adj. monoecious ) is a sexual system in seed plants where separate male and female cones or flowers are present on the same plant. It is a monomorphic sexual system alongside gynomonoecy, andromonoecy and trimonoecy. Monoecy is conne ...

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

provide a wide range of local uses and are commonly called bertam or wild Bornean sago. The genus is the sole representative of the Eugeissoninae having very few obvious relatives; the

hermaphrodite In reproductive biology, a hermaphrodite () is an organism that has both kinds of reproductive organs and can produce both gametes associated with male and female sexes. Many Taxonomy (biology), taxonomic groups of animals (mostly invertebrate ...

and staminate flowers are also found in ''

Metroxylon ''Metroxylon'' is a genus of monoecious flowering plants in the Arecaceae (palm) family, and commonly called the ''sago palms'' consisting of seven species. They are native to Western Samoa, New Guinea, the Solomon Islands, the Moluccas, the C ...

'', however the other specialized characteristics are unique suggesting an early split and differentiation from other members of the Calameae.Uhl, Natalie W. and Dransfield, John (1987) ''Genera Palmarum - A classification of palms based on the work of Harold E. Moore''. Lawrence, Kansas: Allen Press. / Fossilized

pollen Pollen is a powdery substance produced by seed plants. It consists of pollen grains (highly reduced microgametophytes), which produce male gametes (sperm cells). Pollen grains have a hard coat made of sporopollenin that protects the gametophyt ...

belonging to these plants has been recovered in the lower and middle

Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recen ...

deposits in

Sarawak Sarawak (; ) is a States and federal territories of Malaysia, state of Malaysia. The largest among the 13 states, with an area almost equal to that of Peninsular Malaysia, Sarawak is located in northwest Borneo Island, and is bordered by the M ...

. The name is from two Greek words meaning "good" and "roof", due to their common use in roof

thatching Thatching is the craft of building a roof with dry vegetation such as straw, water reed, sedge (''Cladium mariscus''), rushes, heather, or palm branches, layering the vegetation so as to shed water away from the inner roof. Since the bulk of ...

Description

All of the ''Eugeissona'' palms will form above-ground stems where the apical inflorescence will appear toward the final year of the palm life. For the highland native of Borneo they let the palm grow trunk and harvest it just before flowering for it palm heart and the starch ( sago) found inside. Amongst the lowland native, the much sought-after palm heart is harvested before the trunk has been formed. During trunk-forming they are supported by tall masses of stilt roots in which detritus and leaf matter collect, providing nesting to various biota. The large leaves are carried on long, spiny petioles, and the rachises and trunks are also spine-bearing. The erect inflorescence bears some of the largest flowers in the palm family, emerging within the leaf crown featuring both male and bisexual flowers. The fruit is a beaked, ovoid drupe carrying one seed.Riffle, Robert L. and Craft, Paul (2003) ''An Encyclopedia of Cultivated Palms''. Portland: Timber Press. /

Floral microbiome

Eugeissona tristis ''Eugeissona'' is a clustering genus of flowering plant in the palm family native to Borneo, Thailand and Malaysia. The six monoecious species provide a wide range of local uses and are commonly called bertam or wild Bornean sago. The genus is th ...

'', from West Malaysia, is adapted to promote microbial growth in its flowers. It bears robust, long-lived (sometimes over 4 months) flowers which contain abundant yeast populations. In the central chambers of these flowers, yeast fermentation generates a nectar that is almost 4% ethanol. The palm is pollinated by mammals (squirrels, nocturnal

murids In Sufism, a ''murīd'' (Arabic مُرِيد 'one who seeks') is a novice committed to spiritual enlightenment by ''sulūk'' (traversing a path) under a spiritual guide, who may take the title murshid, '' pir'' or ''shaykh''. A ''sālik'' or Suf ...

, and treeshews like the

pentailed treeshrew The pen-tailed treeshrew (''Ptilocercus lowii'') is a treeshrew of the family Ptilocercidae native to southern Thailand, the Malay Peninsula, Borneo, and some Indonesian islands. It is the only living species in the genus ''Ptilocercus''. All ...

) which have adapted to chronic alcohol consumption.

Distribution and habitat

They inhabit a variety of settings including the low-lying heath forests, montane rain forests, and

swamp A swamp is a forested wetland.Keddy, P.A. 2010. Wetland Ecology: Principles and Conservation (2nd edition). Cambridge University Press, Cambridge, UK. 497 p. Swamps are considered to be transition zones because both land and water play a role in ...

s, but are most common on

scarp Scarp may refer to: Landforms and geology * Cliff, a significant vertical, or near vertical, rock exposure * Escarpment, a steep slope or long rock that occurs from erosion or faulting and separates two relatively level areas of differing elevatio ...

faces, hills and rocky ridgetops up to 1000 m. ''E. brachystachys'' and ''E. tristis'' are found solely in Malaysia, while the remainder are Bornean or Thai in origin. ''E. tristis'' has become an effective pest in the Hill Dipterocarp forest where it colonizes cleared timberland preventing the regeneration of various trees.

Cultivation and uses

While not common in cultivation, they are used extensively by locals for a variety of purposes. The sago made from the trunks forms the staple of the

Punan Punan Bah or Punan is an ethnic group found in Sarawak, Malaysia and in Kalimantan, Indonesia. The Punan Bah people are distinct and unrelated to the semi-nomadic Penan people. Their name stems from two rivers along the banks of which they ha ...

diet, and the seed's

endosperm The endosperm is a tissue produced inside the seeds of most of the flowering plants following double fertilization. It is triploid (meaning three chromosome sets per nucleus) in most species, which may be auxin-driven. It surrounds the embryo and ...

and the pollen are also known to be consumed. The leaves are used in roof construction, various thatchings, and the manufacture of blinds. The stilt roots of some species are made into walking sticks and toys, while the petioles are fashioned into darts for

blowgun A blowgun (also called a blowpipe or blow tube) is a simple ranged weapon consisting of a long narrow tube for shooting light projectiles such as darts. It operates by having the projectile placed inside the pipe and using the force created by ...

hunting.

References

External links

''Eugeissona'' on NPGS/GRINGBIF PortalFairchild Guide to Palms: ''Eugeissona''
{{Taxonbar, from1=Q139312, from2=Q21445617 Calamoideae Arecaceae genera Flora of Borneo Flora of Peninsular Malaysia Flora of Thailand