Licuala adscendens Barfod & Heatubun

First published in Kew Bull. 64: 553 (2009)
This species is accepted
The native range of this species is Maluku (Obi). It is a shrub or tree and grows primarily in the wet tropical biome.

Descriptions

Barfod, A.S. & Heatubun, C.D. 2009. Two new species of Licuala Thunb. (Arecaceae: Coryphoideae) from North Moluccas and Western New Guinea. Kew Bulletin 64: 553. DOI: https://doi.org/10.1007/s12225-009-9129-z

Type
Indonesia, North Moluccas, Obi Island, Anggai, GunungBatuPutih, 550 m a.s.l., 1°24′S, 127°48′E, 14 Nov. 1974, de Vogel 4044 (holotypusL!; isotypi BO, CANB!, LAE!, MO!).
Morphology General Habit
Solitary, medium-sized tree up to 3 m tall
Morphology Stem
Stem c. 3 cm in diam., with 10 – 15 mm long internodes and inconspicuous leaf scars
Morphology Leaves
Leaf sheath brown, extending above and attached to the armed part of the petiole, disintegrating irregularly into a narrow band of fibrous mesh, extending into two, up to 40 cm long, strap-shaped appendices, detached from the petiole; petiole to 120 cm long, 15 – 20 mm wide at the base, adaxial face shallowly channelled basally to flattened distally, abaxial face rounded, armed on lower third with relatively delicate, up to 5 mm long, unevenly sized, more or less straight spines; lamina divided along the abaxial ribs into 13 – 15 segments, mid segment with about 20 – 26 adaxial ribs, 40 – 45 cm long, truncate, 27 cm wide at the apex, the remaining segments with 3 – 4 adaxial ribs, basal segment 34 – 40 cm long, obliquely truncate apically, 4.5 – 8 cm wide, indentations leading to both adaxial and abaxial ribs 2 – 5 mm long
Morphology Reproductive morphology Inflorescences
Inflorescences 80 – 100 cm long, erect, with 2 – 3 partial inflorescences; peduncle 15 – 20 cm long; prophyll 26 – 40 cm long, brownish, chartaceous, inserted 4 – 5 cm above the base; peduncular bracts lacking; rachis erect and more or less straight; proximal rachis bract 23 – 35 cm long, inserted 10 – 35 cm above prophyll, splitting irregularly at the apex, covered with patchy tomentum, entirely contained in prophyll to free, partial inflorescences erect, the proximal one with 5 – 6 cm long main axis, branched irregularly into 2 orders, carrying 6 – 12 rachillae, 10 – 20 cm long, adscending and covered with minute, ferruginous, ramentose hairs
Morphology Reproductive morphology Flowers
Flowers solitary or in pairs proximally on the rachilla, borne on up to 2 mm long pedicels, bullet-shaped and about 4 mm long, floral subtending bract and bracteole inconspicuous, putatively unisexual; calyx 2.6 – 2.7 mm long, fused with receptacle for about 0.4 – 0.5 mm, breaking up regularly in three, c. 0.6 – 0.8 mm long, apically rounded to obtuse lobes; corolla c. 3.4 – 3.5 mm long, lobes 1 – 1.2 mm long; androecium 2.5 – 2.6 mm long, fused to corolla for 0.9 – 1.0 mm, staminal ring 0.6 – 0.8 mm high; anthers inserted in two levels, elongate, 0.6 mm long, slightly narrower and dehiscent earlier in putative female flowers; ovary 2.5 – 2.6 mm long, about 1 mm wide and rounded apically in putative female flowers, about 0.6 mm wide and attenuate apically in putative male flowers; style 1 – 1.1 mm long; locules in lower half of gynoecium, about 0.8 – 0.9 mm long in putative female flower; 0.3 – 0.4 mm long in putative male flowers
Morphology Reproductive morphology Fruits
Young fruits with stigmatic remains still attached, 9 – 10 mm long, obovate; seed not seen
Distribution
Known only from a single collection made by Ed de Vogel in Obi Island, North Moluccas.
Ecology
Collected in dense forest on limestone outcrops where it was locally common; 550 m.
Conservation
Data Deficient (DD). Further studies are needed to assess the conservation status of this palm.
Note
Licuala adscendens shows affinities to the morphologically variable species L. lauterbachiiDammer & K. Schum. (in Schumann & Lauterbach 1900: 199), which is widespread in the eastern Malesian region. With this species it shares features such as conspicuously wider and undivided mid-segments of the leaf (Fig. 1A), shortly pedicellate and glabrous flowers (Fig. 1C & E), and stamens that are inserted in two levels (Fig. 1F). It differs by having erect inflorescences (Fig. 1B), short main axes of the partial inflorescences, adscending rachilla branches and larger anthers (Fig. 1F). Some flowers have reduced gynoecia and may be functionally unisexual (Fig. 1G). Further conclusions regarding sexual expression depend upon more studies in the field.
[KBu]

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
[AERP]

Sources

  • Angiosperm Extinction Risk Predictions v1

    • Angiosperm Threat Predictions
    • http://creativecommons.org/licenses/by/4.0
  • Herbarium Catalogue Specimens

  • Kew Backbone Distributions

    • The International Plant Names Index and World Checklist of Vascular Plants 2024. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2023 World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0
  • Kew Bulletin

    • Kew Bulletin
    • http://creativecommons.org/licenses/by-nc-sa/3.0
  • Kew Names and Taxonomic Backbone

    • The International Plant Names Index and World Checklist of Vascular Plants 2024. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2023 International Plant Names Index and World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0