Orania littoralis A.P.Keim & J.Dransf.

Baker, W.J., Barfod, A.S., Cámara-Leret, R., Dowe, J.L., Heatubun, C.D., Petoe, P., Turner, J.H., Zona, S. & Dransfield, J. (2024) Palms of New Guinea. Royal Botanic Gardens, Kew, Richmond. 726 pp.

Morphology General Habit

Small, single-stemmed tree palm to 6 m

Morphology Stem

Stem 14 cm diam., grey

Morphology Leaves

Leaves ca. 12 in crown, spirally arranged, to 6 m long; petiole short, to 2 cm diam., covered with red-brown tomentum; rachis to 4 m long, ca. 2 cm wide in mid-leaf, with red-brown tomentum, leaflets up to 70 on each side of the rachis, regularly arranged in one plane, to 120 cm long, ca. 7 cm wide, upper surface bright green, shiny, glabrous, lower surface with white indumentum and red-brown tomentum along veins

Morphology Reproductive morphology Inflorescences

Inflorescence spreading, branched to 2 orders, to 2.5 m or more long; peduncle ca. 85 cm long, ca. 7 cm diam., with dense red-brown tomentum; peduncular bract persistent, woody to 2.4 m long; rachillae long, numerous, thick, 40–55 cm long, 0.6 cm diam., not zigzag

Morphology Reproductive morphology Flowers

Male flowers ca. 9–10 mm long, stamens 6 Female flowers 4 mm long, staminodes 6, uniform

Morphology Reproductive morphology Fruits

Fruits globose or bilobed, 4.5–5 cm diam., turning orange and red at maturity

Morphology Reproductive morphology Seeds

Seed with embryo above seed equator.

Distribution

Far south-eastern New Guinea. habitat: Lowland rainforest at sea level.

Vernacular

None recorded.

Conservation

Critically Endangered (IUCN 2021). Orania littoralis is known from only one site where it is threatened by logging.

Note

Orania littoralis shares many similarities with both O. ferruginea and O. oreophila. It can be distinguished by the much longer rachillae with relatively fewer flower clusters.

Extinction risk predictions for the world's flowering plants to support their conservation (2024). Bachman, S.P., Brown, M.J.M., Leão, T.C.C., Lughadha, E.N., Walker, B.E. https://nph.onlinelibrary.wiley.com/doi/full/10.1111/nph.19592

Conservation

Predicted extinction risk: threatened. Confidence: confident

Keim, A.P. & Dransfield, J. 2012. Kew Bulletin 67: 127. https://doi.org/10.1007/s12225-012-9356-6

Morphology General Habit

Small palm

Morphology Trunk

Trunk 6 m tall, c. 14 cm diam. (dbh), internodes 5 – 5.5 cm, leaf scars inconspicuous basally, visible on upper part, 3.5 – 4 cm wide below crown

Morphology Reproductive morphology Inflorescences

Inflorescence spreading, branching to 2 orders, c. 245 cm long; prophyll persistent, c. 63 cm long, disintegrating into fibres when old, adaxial surface greenish yellow, glabrous, abaxial surface with red-brown tomentum; peduncle c. 85 cm long, c. 7 cm diam., with dense red-brown tomentum, c. 3.5 cm diam.; peduncular bract one, woody, c. 240 cm long, acuminate tip, c. 42 cm long, adaxial surface glabrous, abaxial surface with dense red-brown tomentum, splitting in the middle, disintegrating into fibres; rachis c. 160 cm long, with dense red-brown tomentum; first order branches 23, c. 63 – 80 cm each; rachillae thick, not robust, straight, not conspicuously zigzag, c. 40 – 65 cm long, bearing 70 – 78 flower clusters, triads arranged in the half part, c. 2 cm devoid of flowers, triads c. 2 – 2.5 cm distant, rachilla with sparse red-brown tomentum

Morphology Reproductive morphology Flowers

Pistillate flowers with calyx of 3 united sepals, 1 mm long; corolla with 3 free petals, c. 4 mm long, 3.5 – 4 mm wide; staminodes 6, c. 2 mm long, uniform, tips not hooked; gynoecium dark blackish brown, c. 3 mm long, 4 mm wide, stigma of 3 elongate lobes, 0.8 – 0.9 mm long Staminate flowers with calyx of 3 united sepals, c. 1 mm long; corolla with 3 free petals, c. 9 – 10 mm long, 2 mm wide; stamens 6, filaments free, dark-brown, c. 1 mm long, anthers elongate-lanceolate, pale creamy yellow, always free, c. 6 – 7 mm long; pistillode absent

Morphology Reproductive morphology Fruits

Fruit globose or bilobed, c. 4.5 – 5 cm diam., stigmatic remains sub-basal, mature orange to red; endosperm white or creamy white, c. 3 – 3.5 cm diam. Embryo placed below middle line of seed

Morphology Leaves

Eophyll bifid Leaves 12 in crown, spirally arranged, c. 6 m long each; leaf-sheath c. 2 m long, margin disintegrating into fibres, adaxial surface glabrous, abaxial surface with dense red-brown tomentum; petiole short, c. 2 cm diam., with dense red-brown tomentum; rachis c. 4 m long, c. 2 cm diam., with dense red-brown tomentum; leaflets elongate-lanceolate, regularly-arranged leaflets held in one plane, leaflets c. 8 cm distant in the middle part of rachis, c. 67 leaflets on each side of rachis, c. 120 cm long, c. 7 cm wide, adaxial surface bright green, shiny, main vein obvious, other veins slender, abaxial surface with dense white indumentum and red-brown tomentum on main vein, other veins slender, glabrous

Distribution

New Guinea. Endemic to an area within the Milne Bay Province, Papua New Guinea. Map 7.

Ecology

Lowland rainforest at about sea level.

Conservation

Critically endangered (CR). The palm is known only from its type, collected at the end of a logging road. It seems highly likely that the palm is threatened with further logging in the area.

Vernacular

Unknown.

Note

Orania littoralis shares many similarities with both O. ferruginea and O. oreophila. However, several morphological characters can be used to distinguish them (Table 11). In terms of habitat preferences, O. littoralis differs from O. oreophila in growing in lowland forest at sea-level compared with the montane O. oreophila. Seacoast-loving.

Use

Unknown.