Scientific name: Podocarpus costalis C. Presl 1849

Synonyms: Nageia costalis (C.Presl) Kuntze

Common names: Seabluff podocarp, Igem-dagat (Philippines), Lan yu luo hang song (Chinese)

Description

Shrubby tree to 5 m tall. Bark smooth, greenish, peeling in thin flakes. Crown broad, with numerous horizontal, contorted branches bearing branchlets densely clothed with foliage. Twigs short, stout, light green, inconspicuously grooved between the attached leaf bases. Resting buds nearly spherical, 2-4 mm long, tightly wrapped by triangular bud scales with spreading tips. Leaves densely and evenly standing out from or forward around and along the twigs or more concentrated near the tips, leathery, lasting 2-4 years, dull bluish green above, yellowish green beneath, (2.5-)4-7 cm long (to 9 cm in juveniles), (5-)7-10 mm wide (to 13 mm in juveniles). Blades straight, the margins flat or slightly turned down, widest beyond the middle, tapering abruptly to a roundly triangular, round, or even slightly notched tip and gradually to a wedge-shaped base on a short petiole 2-3 mm long. Midrib fairly prominently raised above, more broadly and shallowly raised beneath, with three resin canals beneath the midvein, wings of support tissue extending out to the sides, and a partial hypodermis beneath the upper epidermis. Pollen cones 2.5-3.5 cm long and 6-8(-10) mm wide, one directly in the axils of the foliage leaves. Pollen scales with a narrow, tonguelike, upturned tip about 3 mm long. Seed cones on a short, leafless stalk (2-)4-6(-10) mm long, with a pair of 1.5 mm long needlelike bracteoles that are quickly shed, the reproductive part with two unequal bracts, these and the axis becoming swollen and juicy, bright red to purple, (7-)10-15 mm long by 8-9 mm thick. Fertile seed scale one, the combined seed coat and epimatium leathery over a hard inner shell, dark blue, (7-)9-10 mm long by 6-8 mm thick, with an inconspicuous beak.

Restricted to the Babuyan, Batan, and Lanyu Islands between Luzon (Philippines) and Taiwan, the Polillo Islands off the eastern coast of Luzon, and the Bucas Islands off northern Mindanao (Philippines). Coastal thickets among rocks on bluffs at the shoreline of small islands (hence the scientific name, Latin for “coastal”);0-300 m.

Conservation Status

Red List Category & Criteria: Endangered

The area of occupancy (ca. 24 km2) is well within the threshold for Endangered and the continuing removal of mature individuals for horticulture and/or pot plants is depleting the population. The population is also severely fragmented. Hence it is listed as Endangered. The total population is thought to be decreasing due to over collecting for the horticultural trade. Podocarpus costalis occurs on islands in lowland evergreen scrub to low forest on karst limestone bluffs and ridges or sea-stacks, from near sea level to at least 300 m a.s.l. It may be native in similar habitat on the northern coast of Luzon. Podocarpus costalis has a very limited distribution in fewer than five localities (islands) and is restricted to a specific habitat. It is in decline because plants are taken from the wild to be planted in gardens in Luzon and Taiwan, and possibly elsewhere. It was listed on Appendix I of CITES in 1975, but deleted from the Appendices in 1990. This attractive, shrubby dwarf tree is popular in cultivation for gardens in the Philippines and in Taiwan, where it has been confused with Podocarpus polystachyus. The pollen cones of Podocarpus costalis are much more robust (up to three times wider) and its leaves shorter and more crowded. The ripe receptacle of the seed cone is dark purple-pruinose, not red. Podocarpus costalis is also used in bonsai culture. This species is legally protected in the Philippines and Taiwan: collecting from the wild is illegal. Attempts should be made to grow this species from seed or scions in order to minimize the taking of plants from the wild.

References

Farjon, A. (2010). A Handbook of the World's Conifers. Koninklijke Brill, Leiden.
Eckenwalder, J.E. (2009) Conifers of the World: The Complete Reference. Timber Press, Portland.
IUCN Red List of Threatened Species, International Union for Conservation of Nature and Natural Resources. Cambridge, UK /Gland, Switzerland