Podocarpus affinis

Seem. 1868

Common names

Kuasi [Fijian], also the local name for Podocarpus neriifolius (Smith 1979).

Taxonomic notes

Syn.: Nageia affinis (Seem.) Kuntze 1891 (Farjon 1998). Type: Fiji: Viti Levu, "forming the principal part of the vegetation of the summit of Voma Peak" Seemann 574 (holotype K), collected in 1860.08.24 (Smith 1979, Farjon 2010).

Podocarpus affinis occurs in close proximity to P. neriifolius, closely resembles it, and occurs at relatively higher elevations on isolated mountainous islands. By the theory of island biogeography (Mac Arthur and Wilson 1967) we would therefore expect that it formerly occurred at lower elevations and was excluded from that niche. Such exclusion could have happened in various ways, by ecological change, or competition with P. neriifolius, or speciation from P. neriifolius into the higher-elevation niche. The molecular analysis by Knopf et al. (2011) placed the two species into different clades, but P. affinis is sister to a larger clade that includes P. neriifolius. Moreover, if we treat P. decipiens as synonymous with P. neriifolius, then these taxa share a clade. Given these molecular findings, coupled with the generally high congruence between geography and systematic relationships within Podocarpus, it is likely that P. affinis is closely related to P. neriifolius and may warrant status as a variety.

Description

Trees to 20 m tall with short, spreading branches. Twigs slender, round, with small terminal buds of erect, free, narrowly triangular scales. Leaves on saplings similar to those on mature trees; oblanceolate to linear-elliptic, 25-50 × 6-9 mm, widest at or above the middle, coriaceous, tapering to a petiolate base, margins slightly revolute, apex obtuse to rounded, lustrous green on upper surface and dull brownish green beneath, with a narrow adaxial midrib, similar on lower side but fading toward apex; stomata abaxial, very small, in many irregular lines. Seed cones green when immature, red when mature, seed glaucous (Farjon 2010, Stauffer and Kuruvoli 1964).

The only other Fijian podocarp, P. neriifolius, has much larger leaves (6-15 cm long) with an acute apex (Smith 1979).

Distribution and Ecology

Fiji: Viti Levu, Namosi, Voma Peak (Farjon 1998). It has been found at 900-1200 m elevation in tropical rainforest, in the understory or dominant in areas of low canopy (Farjon 2010). It has been described as a component of the Quasi-Montane forest type, where it is associated with other conifers including Dacrydium nidulum, Agathis macrophylla, and Acmopyle sahniana (Tuiwawa et al. 2021).

The IUCN has assigned this species a "Near Threatened" conservation status. It has a very small extent of occurrence and area of occupancy, but is known from at least 5 locations and does not appear to have experienced substantial habitat fragmentation. There is likely some ongoing decline in extent and quality of habitat. Potential threats from climate change include an upslope shift of the cloud layer that could result in reduced humidity and decreased water availability. Deforestation is a risk to lower-elevation populations. The species is not known to occur in any conservation reserves, and otherwise receives little protection (Thomas 2013). Also see Keppel et al. (2015) for more current population information which, however, does not alter the conclusions of the assessment.

Remarkable Specimens

No data as of 2023.01.04.

Ethnobotany

Seemann (1868) reported that "The natives use the wood for outriggers of canoes," but this was cited as misinformation by Smith (1979), who declares "it is unlikely that this rare and small tree has any local uses." The resource is now depleted and no ongoing uses are known (Farjon 2010).

Observations

No records on iNaturalist as of 2023.01.04.

Remarks

The epithet means "allied to"; Seemann thought it closely related to Podocarpus elatus, although more recent analyses indicate otherwise.

Citations

Keppel, Gunnar, Alivereti Naikatini, Isaac Rounds, Robert Pressey, and Nunia Thomas. 2015. Local and expert knowledge improve conservation assessment of rare and iconic Fijian tree species. Pacific Conservation Biology https://doi.org/10.1071/PC14920.

Mac Arthur, Robert H. and Edward O. Wilson. 1967. The Theory of Island Biogeography. Princeton University Press.

Seemann, Berthold. 1868. Flora Vitiensis, p. 266. Available: Biodiversity Heritage Library, accessed 2023.01.04.

Smith. 1979. Flora Vitiensis Nova, vol. 1, p. 102. Available: Biodiversity Heritage Library, accessed 2023.01.04.

Stauffer, H. U. and J. Tavioli Kuruvoli. 1964. Notes on herbarium sheet, Naturalis Biodiversity Center, accessed 2023.01.04.

Thomas, P. 2013. Podocarpus affinis. The IUCN Red List of Threatened Species 2013: e.T31053A2801991. https://dx.doi.org/10.2305/IUCN.UK.2013-1.RLTS.T31053A2801991.en, accessed 2023.01.04.

Tuiwawa, Marika, Sarah Pene, and Linton Winder. 2021. Vegetation patterns in Waisoi primary rainforest, southeast Viti Levu, Fiji. Pacific Science 74. https://doi.org/10.2984/74.3.2.

See also

The species account at Threatened Conifers of the World.

Gray, Netta E. 1958. A Taxonomic Revision of Podocarpus, XI. The South Pacific Species of Section Podocarpus, Subsection B. Journal of the Arnold Arboretum 39:445. Available: Biodiversity Heritage Library, accessed 2023.01.08.