Hydriastele dransfieldii

Hydriastele (high-dree-Ah-STEL-eh) dransfieldii (dranz-feeld'-ee)
Fairchild Tropical Garden, Florida. Photo by Dr. Scott Zona/Palmweb.
Scientific Classification
Genus: Hydriastele (high-dree-Ah-STEL-eh) Species: dransfieldii (dranz-feeld'-ee)
Synonyms
None set.
Native Continent
Oceania
Morphology
Habit: Solitary Leaf type: Pinnate
Culture
Survivability index
Common names
Ombrush (Biak language).

Habitat and Distribution

Papua New Guinea, Biak Island. Reported from Supiori and Numfoor Islands by

Forest on limestone along Jalan, Papua, Biak, Indonesia. Photo by Dr. William J. Baker, Royal Botanic Gardens, Kew/Palmweb.

Biak islanders. In forest on limestone between sea level and 310 m, often growing in very thin soils and occasionally in cracks in limestone.

Description

Solitary pleonanthic, moderately robust palm; stems up to 1,2 m tall, 5-12 cm in diam.; internodes 3.0-1 1.5 cm long, nodal scars not always conspicuous. Leaves 6-10 in the crown, pinnate, 1.3-3.0 m long (including petiole), neatly abscising; sheaths tubular, 35-80 cm long, covered with thin, finely floccose, dark brown indumentum; crownshaft well defined, up to 12O cm long and up to 20 cm in diam.; petiole 10-65 cm long and 1.5-3.0 cm in diam., channeled adaxially, rounded abaxially, indumentose at junction with sheath, otherwise with copious minute, dark scales; rachis somewhat arching, with adaxial longitudinal ridge, rounded abaxially, indumentose as sheath, indumentum sometimes more dense and coarse than on sheath, sometimes absent with only scattered scales remaining, indumentum possibly lost with age; blade variously divided into 1-19 fold leaflets, typically including 3 pairs of multiple-fold leaflets, interspersed with very few pairs of single-fold leaflets; leaflet with praemorse apical margin, 65-130 cm long, 1.5-30 cm wide, individual folds 1.5-3.5 cm wide, terminal pair of leaflets always multiple-fold (about 10-14 folds) forming flabellum with cleft apex; Iamina with numerous minute brown dots on both sides, transverse veinlets inconspicuous, adaxial surface paler when dried, main veins with very few minute hairs adaxially and brown ramenta abaxially. Inflorescence infrafoliar, 37-41, cm long at anthesis, apparently growing to about 52 cm long in fruit, protandrous, branching to 1 order; peduncle 2-5 cm long, glabrous; prophyll 43-46 cm long, 5-8 cm wide, borne about half way up the peduncle, tubular, lanceolate, Z-keeled, membranous, glabrous, entirely enclosing the inflorescence, then splitting longitudinally and falling before staminate anthesis; peduncular bracts 1-3, first peduncular bract borne 8-10 mm above the prophyll, similar to the prophyll in shape and size, but lacking keels, remaining peduncular bracts inconspicuous and incomplete; rachis 1-2 cm long; rachis bracts inconspicuous, incompletely sheathing; rachillae 4-LI, 30-36 cm long at anthesis, apparently growing to about 49 cm long in fruit, 2.0-3.5 mm wide, borne at a very acute angle to the rachis, apparently rather stiff and straight, or pendulous when heavy with fruit, sometimes sinuous in distal-most portion, bearing triads in opposite and decussate pairs, except in distal-most and proximal-most portion of rachilla where arranged spirally, triads 4-6 mm apart; rachilla bracts very inconspicuous, low, rounded; floral bracteoles low, rounded, similar to rachilla bract. Staminate flowers 9-11 mm long, asymmetrical; sepals 3, greenish white, connate, triangular, 2 mm long; petals 3, white, briefly connate at the base, falcate, acuminate, much exceeding the calyx, 1 petal much larger than the others, 10-11 x 4-5 mm, smaller petals 9-10 x 2-3 mm; stamens 13-16 (very rarely as few as 9); filaments slender, about 0.5 mm long, sometimes briefly epipetalous near base of petal; anthers linear, 5-6.5 mm long, about 0.6 mm wide, basifixed, dehiscence latrorse, connective prolonged into an acute appendage, about 0.5 mm long; pollen unknown; pistillode absent. Pistillate flowers about 9 x 5 mm long at anthesis, perianth apparently continuing to grow as fruit develops, flower scar 2.5-4 x,2-3 mm; calyx greenish white, synsepalous, forming cylindrical tube, about 3 mm long, about 5 mm wide, margin with 3 very short lobes; corolla white about 8.5 mm long, about 5 mm wide, sympetalous for half its length, with 3 free lobes, the two parts separated by a dark equatorial ridge (visible only in herbarium material); corolla lobes about 4 mm long, very thick, valvate, tightly closed during staminate anthesis, adaxial surface thrown into minute folds and tubercles, drytng after pistillate anthesis, becoming hard and brittle, and often caducous; staminodes 3-5(6?), minute, triangular; gynoecium white, 5.5 mm long, 3.5 mm wide, obovoid, uniloculaq uniovulate, locule located near the base of the ovary, ovary wall rather fibrous; stigmas 3, lobes less than 1 mm long, fleshy, slightly recurved, stigmatic surface forming deep, narrow invagination into the ovary wall at the iunction of the 3 lobes. Fruit obovoid, about 18 mm long, about 12 mm wide, with conspicuous woody discoid depression at apex, about 5 mm in diam., stigmatic remains persistent in centre of depression, perianth persistent, corolla lobes becoming hardened with age and often caducous; epicarp smooth, thin, ripening through yellow to red when mature, with copious tannin bodies beneath; mesocarp fibrous, about 1 mm thick, but much thicker below stigmatic remains; endocarp very thin, adhering closely to seed; seed subglobose, about 8 x 7 mm, with small basal depression and shallow longitudinal groove; endosperm deeply ruminate; embryo basal. (W.J. Baker, R.A. Maturbongs, J. Wanggai and G.G. Hambali. 2000)/Palmweb. Editing by edric.

Comments and Curiosities

Etymology: The species is named for John Dransfield (eminent English palm botanist) in recognition of his monumental contribution to the taxonomy of palms in Southeast Asia. (W.J. Baker, R.A. Maturbongs, J. Wanggai and G.G. Hambali. 2000)/Palmweb.

Uses: Seed as substitute for betel nut, leaves for wrapping meat or sago. (W.J. Baker, R.A. Maturbongs, J. Wanggai and G.G. Hambali. 2000)/Palmweb.