Sommieria Becc., Malesia 1: 66 (1877)

Primary tabs

https://media.e-taxonomy.eu/palmae/photos/palm_tc_192924_2.jpg

Distribution

Map uses TDWG level 3 distributions (https://github.com/tdwg/wgsrpd)
New Guinea present (World Checklist of Arecaceae)B
A single species confined to New Guinea where it occurs predominantly in the western half of the island. (Dransfield, J., Uhl, N., Asmussen, C., Baker, W.J., Harley, M. & Lewis, C. 2008: Genera Palmarum. The evolution and classification of palms)A

Discussion

  • Heatubun (2002) showed convincingly that variationin this genus does not warrant the recognition of more thanone species. (Dransfield, J., Uhl, N., Asmussen, C., Baker, W.J., Harley, M. & Lewis, C. 2008: Genera Palmarum. The evolution and classification of palms)A

Diagnosis

  • Short, sometimes acaulescent palm of forest undergrowth in western New Guinea, with entire-bifid or irregularly pinnate strongly discolourous leaves and small corky-warted fruit. (Dransfield, J., Uhl, N., Asmussen, C., Baker, W.J., Harley, M. & Lewis, C. 2008: Genera Palmarum. The evolution and classification of palms)A

Biology And Ecology

  • Confined to the undergrowth of humid lowlandtropical rain forest. (Dransfield, J., Uhl, N., Asmussen, C., Baker, W.J., Harley, M. & Lewis, C. 2008: Genera Palmarum. The evolution and classification of palms)A

Common Name

  • Mbebmega (Hatam language), som (Biak), man (Bewani). (Dransfield, J., Uhl, N., Asmussen, C., Baker, W.J., Harley, M. & Lewis, C. 2008: Genera Palmarum. The evolution and classification of palms)A

Etymology

  • Commemorating Stephen Sommier (1848–1922), Italian natural historian and friend of Odoardo Beccari. (Dransfield, J., Uhl, N., Asmussen, C., Baker, W.J., Harley, M. & Lewis, C. 2008: Genera Palmarum. The evolution and classification of palms)A

Description

  • Small, solitary, acaulescent to short-stemmed, unarmed, pleonanthic, monoecious palms. Stem eventually erect, becoming bare, ringed with very close leaf scars, sometimes also bearing bunches of aerial roots. Leaves numerous, entire, bifid, sometimes with 2 pairs of segments, pinnately ribbed, marcescent; leaf sheaths densely tomentose, eventually splitting irregularly opposite the petiole and disintegrating into an interwoven mass of fibres, the mouth (?always) prolonged into a fibrous ligule; petiole usually short, adaxially channelled, abaxially rounded, variously tomentose; rachis adaxially channelled near the base, distally angled, abaxially rounded, gradually tapering; blade divided to produce a large, bifid part and 1 pair of narrow acuminate basal segments, or simply bifid, the apical margins lobed, the lobes corresponding to the major folds, or subentire, adaxially minutely scaly (?always), abaxially glabrous or densely white-tomentose, transverse veinlets obscure. Inflorescences ± erect, interfoliar, solitary, ± equalling the leaves, branching to 1 order, protandrous; peduncle very long, slender, ± elliptical in cross-section; prophyll scarcely exserted from the subtending leaf sheath, 2-keeled, tubular, splitting along the abaxial face, the tip somewhat beaked, sometimes tattering into fibres at the tip; peduncular bract 1, tubular, borne at the tip of the peduncle, ± enclosing the rachillae before anthesis, membranous, splitting down one side to the base and becoming lanceolate, apparently sometimes persisting, sometimes deciduous; rachis very short; rachillae few in number (less than 12), spirally arranged, pendulous, ± stiff, slender, elongate, each subtended by a minute first-order bract, the surface of the rachilla densely dark brown-tomentose, flowers arranged in triads, sunken within pits ± throughout the entire length of the rachilla; the rachilla bracts low, minutely toothed, forming the lower lips of the pits; floral bracteoles minute. Staminate flowers ± symmetrical, the base somewhat stalked; sepals 3, distinct, rounded, imbricate, hooded, strongly keeled, ±striate; petals 3, ±twice as long as the sepals, distinct, ovate-triangular, valvate, scarcely opening at anthesis; stamens 6, filaments minutely connate basally, fleshy, awl-shaped, inflexed in bud (?always), the antesepalous much longer than the antepetalous, at anthesis spreading between the petals, the antepetalous included, anthers short, rectangular, medifixed, ± versatile, latrorse; pistillode ± as long as petals, columnar, ± angled. Pollen ellipsoidal asymmetric, occasionally oblate triangular; aperture a distal sulcus, less frequently a trichotomosulcus; ectexine tectate, perforate-rugulate, aperture margin similar or slightly finer; infratectum columellate; longest axis 22–28 µm [1/1]. Pistillate flowers eventually larger than the staminate, ± globular; sepals 3, distinct, or briefly connate, rounded, strongly imbricate; petals ± equalling the sepals, 3, distinct or briefly connate, rounded, imbricate except for the short, triangular, valvate tips; staminodes 3–6, tooth-like; gynoecium unilocular, uniovulate, ovoid, stigmas 3, apical, reflexed, ovule form not known. Fruit small, spherical, perianth whorls persistent, the stigmatic remains basal; epicarp smooth, brown early in development, soon cracking, obsolescent at maturity, mesocarp cracked to form pyramidal to hexagonal, corky warts, brown-tipped, pink-sided and white-based when fresh, drying dull brown throughout, endocarp thin, bony, operculate, closely adhering to the seed. Seed basally attached, spherical, hilum ± circular, raphe branches sparsely anastomosing, endosperm homogeneous; embryo subbasal. Germination adjacent-ligular; eophyll bifid. Cytology: 2n = 34. (Dransfield, J., Uhl, N., Asmussen, C., Baker, W.J., Harley, M. & Lewis, C. 2008: Genera Palmarum. The evolution and classification of palms)A

Anatomy

  • Floral (Stauffer et al. 2004) and fruit (Essig et al.1999). (Dransfield, J., Uhl, N., Asmussen, C., Baker, W.J., Harley, M. & Lewis, C. 2008: Genera Palmarum. The evolution and classification of palms)A

Fossil record

  • No generic records found. (Dransfield, J., Uhl, N., Asmussen, C., Baker, W.J., Harley, M. & Lewis, C. 2008: Genera Palmarum. The evolution and classification of palms)A

Relationships

  • For relationships, see Pelagodoxa. (Dransfield, J., Uhl, N., Asmussen, C., Baker, W.J., Harley, M. & Lewis, C. 2008: Genera Palmarum. The evolution and classification of palms)A

Taxonomic accounts

  • Heatubun (2002). (Dransfield, J., Uhl, N., Asmussen, C., Baker, W.J., Harley, M. & Lewis, C. 2008: Genera Palmarum. The evolution and classification of palms)A

Bibliography

    A. Dransfield, J., Uhl, N., Asmussen, C., Baker, W.J., Harley, M. & Lewis, C. 2008: Genera Palmarum. The evolution and classification of palms
    B. World Checklist of Arecaceae