The Gymnosperm Database

 

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Conservation status 2013

Agathis borneensis

Warb. 1900

Common names

Borneo kauri, Malayan kauri (English); bindang (Sarawak); kayu buloh, bulu (Iban); tolong (Brunei); mengilan, tambunan (Sabah); dammar, dammar daging, dammar minyak, tulong (Malaya); hedje (Tapanuli); salang (Kendayah); manggilam (Dusun); bangalan, bengalan (Sampit, Pilau); toga (W Kutai); bembuëng (SE Borneo); nuju (Dajak); enghatan (Sanggan); pisau, putut (Sintang); bamboeng, bengalen, bindang, mengilan, pilan, tulong (Borneo) (Smythies 1965, Whitmore 1980, Silba 1986, de Laubenfels 1988).

Taxonomic notes

Syn.: A. beccarii Warburg 1900; A rhomboidalis Warburg 1900; A. latifolia Meijer Drees 1940; A. endertii Meijer Drees (1940).

For the moment I continue to treat A. endertii as a good species per de Laubenfels (1988), but the species has been synonymized with A. borneensis by both Whitmore (1980) and Farjon (2010). However, Whitmore provides no explanation of his decision, while Farjon simply asserts that "it is not really distinct in any diagnostic character;" de Laubenfels concludes otherwise. I have not examined either herbarium specimens or trees in habitat and have no personal opinion in the matter; however, I would like to see a more detailed argument for reducing A. endertii to synonymy before dismissing de Laubenfels' work.

Type: A specimen collected by Beccari on Sarawak [locality not stated]. My references on this point conflict: Whitmore (1980) cites Beccari 491, isotypes at BO and K; Farjon (2010) cites Beccari 596, syntype K.

Whitmore (1980) explains that Warburg described A. borneensis and A. beccarii at the same time, but for A. borneensis he provided a male specimen and a good drawing of the microsporophyll, while for A. beccarii he provided only a sterile specimen, with a female isotype for Kew. Thus the A. beccarii specimen does not display characters that allow it to be classified to species, and A. borneenesis becomes the type, with A. beccarii reduced to synonymy. This is unfortunate because it means that one of the most widespread species of Agathis in Malaya and Sumatra now bears the epithet "borneensis."

Description

Trees to 50(-55) m tall and 3.5 m dbh. Mature trees follow the usual Agathis model of a long (20-30 m) clear bole with a broad emergent crown of large rigid first-order branches. Bark variable: grey, light brown, to black, finely dimpled to thinly scaly or rough, exfoliating thus with few epiphytes. Leaves sub-opposite, thick, coriaceous, light green, highly variable even on a single tree, more or less elliptic, acute on young trees, 2.5-14 cm long, generally larger on younger than on mature trees, about 3-10 times as long as wide. Pollen cones axillary, solitary on a stout, 1-2(-5) mm (Malaya and Borneo) or (4-)10 mm (Sumatra) peduncle; ovoid-cylindrical at anthesis, 30-40 × 14-18 mm; ultimately becoming dark brown flexible cylinders, 20 × 50 - 40 × 90 mm. Basal bracts forming a loose flattened cupule adpressed to cone and usually smaller but rarely enclosing it, occasionally cone extending downwards so obscuring the cupule. Microsporophylls large; as seen in intact cone at anthesis strongly imbricate, 4-5 mm across, with a clearly demarcated, erose, usually pale, chartaceous margin; head in adaxial view 5-6 mm across × 4-5 mm radially, often extending axially as 2 truncated wings tipped by anthers; anthers 4-10. Seed cones solitary on thick peduncles, ellipsoid to globose, 10-13 cm across at maturity, resinous, green ripening to brown (Whitmore 1980, Farjon 2010).

The most similar species is A. dammara; indeed the two were synonymized by de Laubenfels (1988), with which no one else has agreed. In portions of their range where the two species coincide, accurate identification requires the pollen cones, which of course are not present on (or beneath) all trees. When they are immature, the pollen cones of A. borneensis are rather globose and become cylindrical by elongation, while those of A. dammara are cylindrical but still small and retain their proportions as they grow. At maturity, the microsporophylls of A. borneensis are much larger than those of A. dammara and have a thin, lighter-colored upper margin (Farjon 2010).

Distribution and Ecology

Sumatra, Borneo and the Malay peninsula below c. 10° N latitude. It occurs from low elevations to c. 1200 m in upland tropical rainforest "and in dense, nearly pure stands on low-lying sandy peat soil in many parts of Borneo and in one area in Malaya." This ecological setting is very similar to that of Dacrydium pectinatum (de Laubenfels 1988); it also occurs with Falcatifolium falciforme, Nageia wallichiana, Sundacarpus amarus, and species of Podocarpus (Farjon 2010).

Remarkable Specimens

No data as of 2023.02.22.

Ethnobotany

No data as of 2023.02.22.

Observations

No data as of 2023.02.22.

Remarks

Citations

See also

The species account at Threatened Conifers of the World.

Meijer-Drees (1940).

Whitmore (1977).

Last Modified 2023-11-01