Podocarpus decumbens | Threatened Conifers of the World (en-GB)

Podocarpaceae

Podocarpus decumbens N.E.Gray

Endemic to New Caledonia where it is only known from three small sites in the south of Grand Terre. Its main threat is from fire

Description

Habit

Decumbent or prostrate shrub, sometimes semi-erect, to ca 40cm. Bark exfoliating with fibrous strips, outer bark yellowish brown.

Foliage

Leaves in tufts borne towards ends of branches, oblanceolate to linear, 4.5–8 x 0.6–0.9cm, leathery, gradually tapering to a pertiole at base, margins revolute, apex narrowing abruptly, obtuse or almost acute. Midrib prominent on upper side, flattened on lower side, light green.

Cones

Male pollen-cones axillary, solitary, sessile, subtended by triangular, keeled bud-scales, 15–30 x 3–3.5mm. Female seed-cones axillary, solitary on a 5–7mm long peduncle; receptacles swelling 8–10cm long, red and succulent, subtended by two 3–4mm long bracts which are made up of 3–4 fused bracts with exserted tips, one being fertile. Seeds solitary 6–7 x ca 4mm Including epimatium)

Distribution

Endemic to New Caledonia in the southern ultramafic massifs of Province Sud on Grand Terre where it occurs in three very small sites on Montagne des Sources and Mont Kouakoué. It has an extent of occurrence of 23km² and an area of occupancy is 8km².

Habitat and Ecology

A prostrate mat-forming shrub (rising to 40cm high) that only occurs in high-altitude (800 to 1000m) maquis in areas of high precipitation where it forms small patches (colonies) up to 20m across.

Conservation Status

Global assessment

Critically Endangered B2ab(iii,v)

Global rationale

This species is only known from three sites in Montagne des Sources and on Mt Kouakoué where it has a extent of occurrence of 23km² and an area of occupancy is 8km². The subpopulations are regarded as severely fragmented due to their geographic and ecological isolation. In Montagne des Sources, recent fires have come very close to destroying one subpopulation.

Global threats

Although all three sites are relatively inaccessible and within protected areas, they are all vulnerable to fires. In Mont Kouakoué, mining is not prohibited. Due to its ecological specificity, this species may also be vulnerable to the predicted effects of climate change

Conservation Actions

All the known localities are within protected areas.

References and further reading

de Laubenfels, D.J. (1972). Flore de la Nouvelle-Caledonie et Dependances. (4). Gymnospermes. Paris: Museum National d'Histoire Narurelle. 167 pp.
Jaffré, T., Munzinger, J. & Lowry, P. P. (2010). Threats to the conifer species found on New Caledonia's ultramafic massifs and proposals for urgently needed measures to improve their protection. Biodiversity and Conservation: 19(5):1485-1502.
Gray, N.E. (1955). A Taxonomic revision of Podocarpus IX. The south Pacific Species of Section Eupodocarpus, Subsection F. Journal of the Arnold Arboretum 36:199-206.
Thomas, P. (2010). Podocarpus decumbens. In: IUCN 2012. IUCN Red List of Threatened Species. Version 2012.1. . Downloaded on 27 September 2012.