''Borassus heineanus'' is a species of a large solitary fan palm found only in northern

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 ...

, in both

Papua New Guinea Papua New Guinea, officially the Independent State of Papua New Guinea, is an island country in Oceania that comprises the eastern half of the island of New Guinea and offshore islands in Melanesia, a region of the southwestern Pacific Ocean n ...

and

Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania, between the Indian Ocean, Indian and Pacific Ocean, Pacific oceans. Comprising over List of islands of Indonesia, 17,000 islands, including Sumatra, ...

, where it is threatened by

habitat loss Habitat destruction (also termed habitat loss or habitat reduction) occurs when a natural habitat is no longer able to support its native species. The organisms once living there have either moved elsewhere, or are dead, leading to a decrease ...

. Also known as the New Guinea palmyra palm, ''B. heineanus'' grows up to 20 m tall with a robust trunk ringed with leaf scars; the old leaves remain attached to the trunk, but eventually fall cleanly. The blueish-green leaves are deeply dissected, up to 3.2 m across and the petioles have very sharp edges, which can give a nasty cut to the unwary. As with all ''Borassus'' species, ''B. heineanus'' is

dioecious Dioecy ( ; ; adj. dioecious, ) is a characteristic of certain species that have distinct unisexual individuals, each producing either male or female gametes, either directly (in animals) or indirectly (in seed plants). Dioecious reproduction is ...

with male and female flowers on separate trees. The male flowers are 1.5 cm long and in semi-circular clusters enclosed within leathery

bract In botany, a bract is a modified or specialized leaf, associated with a reproductive structure such as a flower, inflorescence axis or cone scale. Bracts are usually different from foliage leaves in size, color, shape or texture. They also lo ...

s, forming massive

catkin A catkin or ament is a slim, cylindrical flower cluster (a spike), with inconspicuous or no petals, usually wind- pollinated ( anemophilous) but sometimes insect-pollinated (as in '' Salix''). It contains many, usually unisexual flowers, arra ...

-like

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 ...

s. In contrast, the female flowers are golfball-sized, solitary and rest on the surface of the inflorescence axis. After

pollination Pollination is the transfer of pollen from an anther of a plant to the stigma (botany), stigma of a plant, later enabling fertilisation and the production of seeds. Pollinating agents can be animals such as insects, for example bees, beetles or bu ...

, they develop into green fleshy

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 ...

s, each containing 1-3

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 ...

s. Each seed is contained within a woody endocarp and in some cases, woody flanges inside the endocarp penetrate the seed. ''Borassus heineanus'' differs from all other ''Borassus'' species in that it is found in tropical forests, rather than open

savanna A savanna or savannah is a mixed woodland-grassland (i.e. grassy woodland) biome and ecosystem characterised by the trees being sufficiently widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach th ...

s, resulting in a leaf anatomy resembling forest palms rather than other ''Borassus'' species. This led palm botanist

Odoardo Beccari Odoardo Beccari (16 November 1843 – 25 October 1920) was an Italian botanist famous for his discoveries in Indonesia, New Guinea, and Australia. He has been called the greatest botanist to ever study Malesia. Life Youth and education (18 ...

to suggest that ''B. heineanus'' might be more akin to the forest palm genus '' Borassodendron'', however

DNA Deoxyribonucleic acid (; DNA) is a polymer composed of two polynucleotide chains that coil around each other to form a double helix. The polymer carries genetic instructions for the development, functioning, growth and reproduction of al ...

evidence and

pollen Pollen is a powdery substance produced by most types of flowers of seed plants for the purpose of sexual reproduction. It consists of pollen grains (highly reduced Gametophyte#Heterospory, microgametophytes), which produce male gametes (sperm ...

morphology clearly place ''B. heineanus'' within the genus ''Borassus''.

References

{{Taxonbar, from=Q4944304 Flora of New Guinea heineanus Plants described in 1914 Taxa named by Odoardo Beccari