Hydriastele divaricata

Hydriastele (high-dree-Ah-STEL-eh) divaricata (dih-vahr-ih-KAH-tah)
Hydriastele divaricata. Habit. From Nong Nooch Tropical Botanical Garden (cultivated specimen). Photo: Scott Zona. PETER PETOE, CHARLIE D. HEATUBUN & WILLIAM J. BAKER Phytotaxa 370 (1) © 2018 Magnolia Press.
Scientific Classification
Genus: Hydriastele (high-dree-Ah-STEL-eh) Species: divaricata (dih-vahr-ih-KAH-tah)
Synonyms
None set.
Native Continent
Oceania
Morphology
Habit: Clustering (Soboliferous) Leaf type: Pinnate
Culture
Survivability index
Common names
None.

Habitat and Distribution

Distribution:—Known only from the type locality on the lower slopes of the

Hydriastele divaricata. Habit. From Nong Nooch Tropical Botanical Garden (cultivated specimen). Photo: Scott Zona. PETER PETOE, CHARLIE D. HEATUBUN & WILLIAM J. BAKER Phytotaxa 370 (1) © 2018 Magnolia Press.

Mt. Jaya region (Dransfield et al. 2000) near to Timika in Papua Province, western New Guinea.

Habitat:—The transition zone between lowland alluvial rain forest and heath forest, 100 m. PETER PETOE, CHARLIE D. HEATUBUN & WILLIAM J. BAKER Phytotaxa 370 (1) © 2018 Magnolia Press.

Description

Clustering, very slender understorey palm forming clumps of about 5 stems, to 4.5 m tall. Stem about 9–17 mm in diam. Leaf about 80 cm long including petiole; sheath about 25 cm long; petiole about 27–30 cm long; leaflets 8–12 per side, irregularly to subregularly arranged, divaricate in the basal and middle portion of the leaf, single- or bi-fold, narrowly linear, praemorse apically. Inflorescence 10–12 cm long including 2–2.5 cm peduncle, spicate or branched to 1 order, protandrous; rachillae 1–2; triads spirally arranged. Staminate flower not seen. Pistillate flower 4–4.5 × 3–3.3 mm at early fruiting stage, with free sepals and free petals with conspicuous, triangular tips. Fruit about 12 × 3 mm when ripe, cylindrical, pale green to pinkish, with a distinct, dark, sclerotic zone encircling apical stigmatic remains (up to ca. 2 mm in diam.). Seed about 8 × 2 mm, elongate to cylindrical; endosperm shallowly ruminate. PETER PETOE, CHARLIE D. HEATUBUN & WILLIAM J. BAKER Phytotaxa 370 (1) © 2018 Magnolia Press.

Culture

Cold Hardiness Zone: 10b

Comments and Curiosities

Notes:—Hydriastele divaricata is a very slender understorey palm distinguished by its narrowly linear leaflets, which are widely spreading (divaricate) in the basal and middle section of the leaf. The limited available material displays inflorescences consisting of just one (spicate) or two rachillae, prompting comparison with H. flabellata and H. montana, but these two species have homogeneous endosperm whereas H. divaricata has ruminate endosperm. Hydriastele divaricata is described in more detail by Heatubun et al. (2018). PETER PETOE, CHARLIE D. HEATUBUN & WILLIAM J. BAKER Phytotaxa 370 (1) © 2018 Magnolia Press.