Podocarpus annamiensis

N.E.Gray (1958)

Common names

海南罗汉松 hainan luohansong [Hainan podocarp].

Taxonomic notes

Type: Viet Nam, Bà Nà Hills ("Mt. Bana"), 7-6-1920, E. Poilane 1561 (holotype A). Syn. Podocarpus neriifolius var. annamiensis (N.E.Gray) L.K.Phan.

This species has generally been seen as extremely similar to P. neriifolius and since Gray's 1958 description, some authors have treated it as a good species and others have reduced it to synonymy with P. neriifolius. de Laubenfels (2015) reassessed the infrageneric structure of Podocarpus on morphological grounds and placed P. neriifolius in Podocarpus section Foliolati while placing P. annamiensis in section Globuli, and this requires granting it species rank. The molecular analysis by Khan et al. (2023) did not agree with de Laubenfels' classification, but also placed P. annamiensis sister to P. pallidus in a clade with 6 other species of Podocarpus; its only relationship to P. neriifolius being that both are in subgenus Foliolatus. Available evidence thus shows it to be a distinct taxon, probably warranting species rank, though its precise placement within Podocarpus remains uncertain.

Description

Trees to 16 m tall and 100 cm dbh. Bark pale gray-brown to dark brown. Twigs thick. Terminal foliar buds ovate to globose, 2.5-4 mm diameter, outer scale leaves broad-triangular, keeled, stiff, erect, to 5 mm long; apex acute, apiculate or acuminate; inner scale leaves shorter with a rounded or minutely apiculate apex. Leaves crowded at the tips of the branches, radially spreading, usually straight but are sometimes falcate, 4-10.5(-18) cm × 5-10(-20) mm, 8-10 times as long as wide, broad-linear or linear-lanceolate, occasionally elliptic-lanceolate; coriaceous; adaxial midrib from broadly prominent to flat above, rarely narrowly prominent; abaxial midrib broadly prominent, raised to channelled; stomatal bands abaxial, 3.8-4.5 mm wide, margins flat to revolute; apex abruptly narrowed, obtuse, orbicular or acute; petiole gradually narrowed, 2-6 mm long. Pollen cone buds solitary (occasionally in clusters of 2 or 3), borne in the axils of the lower leaves of the new growth, subsessile, subglobose, 1.5-3 mm diameter, covered in tightly appressed, broadly triangular, stiff bud scales with obtuse to acute apices and scarious margins, strongly keeled; young pollen cones greenish white, mature ones pale yellow, 3-5 cm long. Seed cones axillary, solitary, widely scattered, on a 2-10 mm peduncle, receptacle 4-8 mm long, composed of two fused fleshy almost equal scales with free tips, at maturity orange-red with a glaucous, dark bluish purple epimatium; seed ovoid, not narrowed at the bottom, apex obtuse, apiculate or orbicular, 8-10 mm. long, 6 mm. wide, not crested. Pollination March-April, seed maturity September-October (Gray 1958, Wu and Raven 1999).

"Podocarpus annamiensis differs from P. neriifolius, which is found in nearby regions, in the smaller stiff leaves which are crowded toward the ends of the twigs and in the abruptly obtuse or acute apex of these leaves. The habit and shape of the leaves is much like that of P. macrophyllus but it differs from this species in the leaf anatomy. The stiff leaves also suggest P. polystachyus, but this is a tree of the strand rather than of the mountains, and the pollen cones occur in clusters of as many as five" (Gray 1958). Also, P. annamiensis "differs in the nearly flat upper leaf midribs, overlapping bud scales, and bluntly acute leaves" (de Laubenfels 2015).

Distribution and Ecology

China: Hainan, E Myanmar, Viet Nam; occurs at 600-1600 m elevation on laterite and granitic yellow-earth in tropical montane rainforests and evergreen broad-leaved forests (Wu and Raven 1999). "Frequent summit tree of mountains in the coast range." Cited locales include Bà Nà Hills, Khánh Hòa Province, Quảng Trị province, and "mountain forests" of Hainan (Gray 1958).

The species has seldom been collected, and as long ago as 1999 Wu and Raven could say it was "a vulnerable species in China; only a few trees now remain in unexploited forests in S Hainan." It is likely of conservation concern, perhaps warranting "Endangered" status.

Remarkable Specimens

The largest reported specimens are up to 16 m tall and 3 m in diameter, and are reported from Hainan (Gray 1958).

Ethnobotany

"The wood is excellent for carving and making writing materials and musical instruments" (Wu and Raven 1999).

Observations

Remarks

The epithet refers to Annam, a French colony (1883-1949) approximately coincident with the modern nation of Viet Nam.

Citations

Gray, N. E. 1958. A taxonomic revision of Podocarpus XI. Journal of the Arnold Arboretum 39:451. Available: Biodiversity Heritage Library, accessed 2025.02.22.

Khan, R., Hill, R. S., Liu, J., and Biffin, E. 2023. Diversity, distribution, systematics and conservation status of Podocarpaceae. Plants 12(5):1171. https://doi.org/10.3390/plants12051171.

Laubenfels, D. J. de. 2015. New sections and species of Podocarpus based on the taxonomic status of P. neriifolius (Podocarpaceae) in tropical Asia. Novon 24(2):133–152. https://doi.org/10.3417/2012091.

See also