Prumnopitys taxifolia
Prumnopitys taxifolia, commonly known as mataī and black pine, is a species of tree in the family Podocarpaceae. It is a dioecious evergreen conifer reaching in height, with a trunk up to in diameter, typically inhabiting lowland to montane forests. It is endemic to New Zealand; its range mainly covers the North and South Islands, it is also found on Stewart Island, but is extremely uncommon there. P. taxifolia is a slow-growing tree and is highly shade-tolerant. P. taxifolia is profoundly heteroblastic; its young form is distinct and resembles a divaricating-wiry shrub, which may last for up to 60 years. It is unknown why P. taxifolia developed this characteristic. P. taxifolia has an average lifespan of 600 years, although it may live as long as 1000 years.
Prumnopitys taxifolia was first described by the British botanist Aylmer Bourke Lambert in 1832. The fruits of P. taxifolia are dispersed by fruit-eating animals, and the tree is pollinated by the wind. It is commonly found on mountain slopes in which it grows in fertile and well-drained soils, although it can still grow well in drier climates. P. taxifolias timber is noted for its strength and durability, and was historically used for building bridges and houses, railway sleepers, and furniture-making. The conservation status of P. taxifolia was assessed by the IUCN Red List in 2013 as "Least Concern".
Description
Prumnopitys taxifolia is a species of dioecious evergreen conifer in the family Podocarpaceae, reaching heights of tall, with a trunk of up to in diameter. Branches are initially ascending and eventually become spreading, forming a domed or rounded crown. The bark is thin and smooth ; it has spots, similar to hammer marks, which are red or purplish-brown in colour when fresh, weathering into a dark brown to black colour, and peeling freely into thick flakes. The outer bark itself can vary in colour from a dark brown to an almost black colour. The wood is very dense, hard, and a dark brown to rich yellow-brown colour. P. taxifolia has an average lifespan of 600 years, although it may live as long as 1000 years.Prumnopitys taxifolias young form is distinct and profoundly exhibits heteroblasty. Its young form, which resembles a tangled shrub, is so distinct that the first botanists in New Zealand initially thought they were separate species. Unlike the related miro, P. taxifolia has a distinctive and long-lasting young stage, which is a tangle of slender, flexible, divaricating branchlets that are interspersed with a scattering of leaves. After several decades, the adult tree begins to grow out of the top of the young shrub and the divaricating branchlets will drop off. It is unknown why this species developed this characteristic; one possibility is that the tangled branches are designed to create a warm temperature inside the shrub, hence the species could survive in colder climates, or it may serve as a defence against browsing animals. The young stage can last for up to 60 years.
Young leaves are 5–10 × 1–2 mm long and brown to pale yellow in colour, narrow and tapering, with a pointed tip, and they can have long whip-like shoots. Adult leaves are 10–15 × 1–2 mm long, dark green in colour, glaucous, subdistichous and often apiculate in character. They generally have a broad shape, but can be more pectinate and linear in character, 10–20 mm long, 1.5–2 mm wide. Leaves are widest near the middle, with nearly parallel sides. The midrib is raised on a bluish-green surface, where there are waxy, pale bluish-green bands of stomata. The Canadian botanist, James Emory Eckenwalder, hypothesised that the leaves of P. taxifolia potentially contain unidentified physiologically active compounds.
Like all conifers, P. taxifolia does not produce flowers or true fruits, but instead produces pollen and seed in cones. The species is dioecious, with male and female reproductive structures on separate trees. The ovules are found on short axillary branches, with 3–10 per a 40 mm long spike. P. taxifolias male pollen cones are found on nearly leafless lateral and axillary spikes near the ends of foliage branches. Each spike is yellow in colour, and can have up to 10–30 cones per spike, each 5–12 mm long and approximately 2 mm wide. The seed cones take 12–18 months to mature and are found throughout the year. They are round to oval in shape, fleshy, globe-shaped or nearly spherical, purplish-black in colour, and about 8–10 mm wide. P. taxifolia has a diploid chromosone count of 38.
Phytochemistry
The sap of P. taxifolia contains matairesinol, a compound which could be useful in cancer research.Taxonomy
Classification
Prumnopitys taxifolia is a member of the genus Prumnopitys, which consists of five species across Australasia and South America. P. taxifolia is categorised in the subgenus Prumnopitys. In 2019, British botanist Chris Page transferred six species from Prumnopitys into a genus Page newly described as Pectinopitys. Page retained three species within the genus Prumnopitys, including P. taxifolia. He based his move on cladistic, morphological, and molecular analysis, concluding that Pectinopitys was distinct enough for it to be described as a new genus, rather than retaining it in Prumnopitys. Page also mentioned that Pectinopitys has a diploid chromosone count of 2n = 36, while Prumnopitys has a count of 2n = 38. Khan et al. revealed that Prumnopitys montana of South America, is the closest relative to P. taxifolia. A 2012 study based on rbcL data sequencing revealed that both species are nearly allied to species within the genus Pectinopitys.History
Prumnopitys taxifolia was first described as Dacrydium taxifolium by the British botanist Aylmer Lambert in his work A Description of the Genus Pinus. It is the basionym of the species. P. taxifolia was described as Dacrydium mai and Podocarpus spicatus in 1838. It was attempted to be renamed to Stachycarpus spicatus in 1891 by the French botanist Philippe Édouard Léon Van Tieghem. American botanist David John de Laubenfels described it as Prumnopitys taxifolia in 1978, which is its currently recognised binomial name.Etymology
The etymology of P. taxifolias genus name, Prumnopitys, means 'plum-fruited pine', which derives from the Greek prunum, which means 'plum', and pitys which means 'fir' or 'pine'. The species name refers to the 'yew-like' leaves of the species, deriving from the Latin taxus, which is in reference to Taxus baccata.The species is commonly known as the mataī and or black pine. The word 'mataī' is likely a combination of the Māori language words 'mata', meaning 'unripe', and 'ī' meaning 'fermented' or 'sour'; likely referring to the bitter taste of resin exuded by the trunk. In 1907, New Zealand ethnographer Elsdon Best recorded that young trees are known in Māori as kāī, kākāī, and māī. The British missionary Richard Taylor, recorded that mature trees were also known as te mai.
Ecology
Prumnopitys taxifolias seeds are dispersed by fruit-eating animals. A 2012 study found that P. taxifolia seeds can still germinate after being excreted by feral pigs, with a success rate of 57 percent. A 2021 study hypothesised P. taxifolias seeds were consumed by the extinct little bush moa, although in low quantities when compared to other native species at the studied site at Borland Burn in Fiordland National Park. The seeds of P. taxifolia reflect some ultraviolet radiation, which is visible to some species of birds and vertebrates, although they do not reflect as strongly as Dacrycarpus dacrydioides. The seeds of P. taxifolia are eaten by the endemic moth, Heterocrossa iophaea. P. taxifolia is a host to the native insects, Ambeodontus tristis and Prionoplus reticularis.Beveridge noted that sixty blackbirds were observed feeding on P. taxifolia seeds at Minginui. The kākā have been recorded destroying the seeds of P. taxifolia. A 1989 study, published in the New Zealand Journal of Ecology, recorded the kererū, kōkako, tūī, and weka as dispersers of the seeds of P. taxifolia. In 2023, a study published in MycoKeys, examined three new Chaenothecopsis lichen species that grow primarily on the exudates of P. taxifolia. One of these species, C. matai, was named in honour of the tree. Like all conifers, the ovules of P. taxifolia are pollinated by the wind. The cones of P. taxifolia have an elongated central axis with about twelve ovules. Each ovule is positioned beneath arranged bracts. At the base of each bract, there is a groove that forms a small gutter around the ovule. During pollination, pollen collects into the grooves before and after a drop of secretion appears, helping to capture pollen efficiently. P. taxifolia is sensitive to fire and has a moderate flammability rate.
Distribution
Prumnopitys taxifolia is endemic to New Zealand; its range primarily covers the North and South Islands. It also occurs on Stewart Island, but it is extremely uncommon there. In The Forest Flora of New Zealand, published in 1889, Thomas Kirk reported only one solitary specimen growing on the southern side of Halfmoon Bay. P. taxifolia commonly coincides with Nothofagus species in the South Island's West Coast Region. Kirk noted in his 1889 revision of New Zealand plants that the species was very common in the central areas of the North Island and in the western and south-western parts of the South Island.The conservation status of P. taxifolia was assessed by the IUCN Red List in 2013 as "Least Concern", and its population trend was evaluated as "Stable". Its assessment in the New Zealand Threat Classification System was evaluated in 2023 as "Not Threatened".