''Metroxylon'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

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 comparable with gynomonoecy, andromonoecy and trimonoecy, and contras ...

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (). The term angiosperm is derived from the Ancient Greek, Greek words (; 'container, vessel') and (; 'seed'), meaning that the seeds are enclosed with ...

s in the

Arecaceae The Arecaceae () is a family (biology), family of perennial plant, perennial, flowering plants in the Monocotyledon, monocot order Arecales. Their growth form can be climbing palm, climbers, shrubs, tree-like and stemless plants, all commonly k ...

(palm) family, and commonly called the ''sago palms'' consisting of seven

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

. They are native to

Western Samoa Samoa, officially the Independent State of Samoa and known until 1997 as Western Samoa, is an island country in Polynesia, part of Oceania, in the South Pacific Ocean. It consists of two main islands ( Savai'i and Upolu), two smaller, inhabit ...

New Guinea New Guinea (; Hiri Motu: ''Niu Gini''; , fossilized , also known as Papua or historically ) is the List of islands by area, world's second-largest island, with an area of . Located in Melanesia in the southwestern Pacific Ocean, the island is ...

, the

Solomon Islands Solomon Islands, also known simply as the Solomons,John Prados, ''Islands of Destiny'', Dutton Caliber, 2012, p,20 and passim is an island country consisting of six major islands and over 1000 smaller islands in Melanesia, part of Oceania, t ...

, the

Moluccas The Maluku Islands ( ; , ) or the Moluccas ( ; ) are an archipelago in the eastern part of Indonesia. Tectonically they are located on the Halmahera Plate within the Molucca Sea Collision Zone. Geographically they are located in West Melanesi ...

, the Carolines and

Fiji Fiji, officially the Republic of Fiji, is an island country in Melanesia, part of Oceania in the South Pacific Ocean. It lies about north-northeast of New Zealand. Fiji consists of an archipelago of more than 330 islands—of which about ...

in a variety of habitats, and cultivated westward to

Thailand Thailand, officially the Kingdom of Thailand and historically known as Siam (the official name until 1939), is a country in Southeast Asia on the Mainland Southeast Asia, Indochinese Peninsula. With a population of almost 66 million, it spa ...

and Malaya.Kew World Checklist of Selected Plant Families
/ref> The name is a combination of two Greek words: meaning "womb", commonly translated as "heart" in this context, and meaning "wood", in allusion to the large proportion of pith contained in the plant.

Description

The trunks of ''Metroxylon'' species are solitary or clumped and large to massive in size, and usually sprout aerial roots at leaf-scar rings. All but one is

monocarpic Monocarpic plants are those that flower and set seeds only once, and then die. The term is derived from Greek (', "single" + , "fruit" or "grain"), and was first used by Alphonse de Candolle. Other terms with the same meaning are '' hapaxanth'' ...

( hapaxanthic),

foliage A leaf (: leaves) is a principal appendage of the stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, f ...

pinnate Pinnation (also called pennation) is the arrangement of feather-like or multi-divided features arising from both sides of a common axis. Pinnation occurs in biological morphology, in crystals, such as some forms of ice or metal crystals, and ...

with oversized petioles and leaf sheaths. The petioles are distinguished by "groups of small black spines resembling the record made by a

seismograph A seismometer is an instrument that responds to ground displacement and shaking such as caused by quakes, volcanic eruptions, and explosions. They are usually combined with a timing device and a recording device to form a seismograph. The out ...

as it registers a mild tremor".Riffle, R. L. and Craft, P. (2003). ''An Encyclopedia of Cultivated Palms''. Portland: Timber Press. / (page 389) All species have spines on the

rachis In biology, a rachis (from the [], "backbone, spine") is a main axis or "shaft". In zoology and microbiology In vertebrates, ''rachis'' can refer to the series of articulated vertebrae, which encase the spinal cord. In this case the ''rachi ...

and petiole. The monocarpic species present a

Christmas tree A Christmas tree is a decorated tree, usually an evergreen pinophyta, conifer, such as a spruce, pine or fir, associated with the celebration of Christmas. It may also consist of an artificial tree of similar appearance. The custom was deve ...

shaped

inflorescence In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a mai ...

, or instead, upward-reaching branches spreading horizontally. These

panicle In botany, a panicle is a much-branched inflorescence. (softcover ). Some authors distinguish it from a compound spike inflorescence, by requiring that the flowers (and fruit) be pedicellate (having a single stem per flower). The branches of a p ...

s are second only to '' Corypha'' spp in size, in the case of '' Metroxylon salomonense'' growing up to thirty feet (nine meters) in height by up to in width. The

fruit In botany, a fruit is the seed-bearing structure in flowering plants (angiosperms) that is formed from the ovary after flowering. Fruits are the means by which angiosperms disseminate their seeds. Edible fruits in particular have long propaga ...

, covered in tough shiny scales arranged in precise rows, are relatively large for palms and contain one

seed In botany, a seed is a plant structure containing an embryo and stored nutrients in a protective coat called a ''testa''. More generally, the term "seed" means anything that can be Sowing, sown, which may include seed and husk or tuber. Seeds ...

Extant species

It contains the following species WCSP, World Checklist of Arecaceae
''Metroxylon''

References

Arecaceae genera Taxonomy articles created by Polbot {{palm-stub