Pogonotium J.Dransf., Kew Bull. 34: 763 (1980)

Primary tabs

http://media.e-taxonomy.eu/palmae/photos/palm_tc_162079_2.jpg

Distribution

Map uses TDWG level 3 distributions (http://www.nhm.ac.uk/hosted_sites/tdwg/geogrphy.html)

Three species, one in Malay Peninsula and Sarawak (Borneo), the other two confined to Sarawak. (J. Dransfield & N. Uhl & C. Asmussen & W.J. Baker & M. Harley & C. Lewis, Genera Palmarum. The evolution and classification of palms. 2008)A

Discussion

Diagnosis

Biology And Ecology

Etymology

Uses

Description

  • Solitary or clustered, spiny, erect or short-climbing, pleonanthic, dioecious, rattan palms. Stem with short internodes. Leaves pinnate, without cirrus; sheath tubular, densely armed with whorled and scattered spines and caducous tomentum, terminating in 2 erect, narrow auricles, 1 on each side of the petiole, the auricles variously armed like the sheath; knee absent or poorly developed; flagellum absent; petiole well developed, flat adaxially, rounded abaxially, armed with reflexed grapnel spines and various papillae and hairs; rachis armed as the petiole; leaflets few to very numerous, linear, single-fold, regularly arranged, very crowded to very distant, the surface covered with a variety of bristles and scales, midribs prominent adaxially, transverse veinlets short, conspicuous. Inflorescences axillary but adnate to the internode and leaf sheath of the following leaf, held erect between the 2 auricles of the subtending leaf, ± sessile, the pistillate branching to 2 orders, the staminate to 3 orders; prophyll enclosing the inflorescence, boat-shaped, with a flattened beak, armed or unarmed, splitting longitudinally along the mid adaxial or abaxial line, thus exposing the flowers; rachis bracts very much smaller than the prophyll, with free tips, each and the prophyll subtending a variously hairy branch; bracts on first-order branches tubular at the base, with triangular limbs. Staminate flowers solitary, borne subdistichously on branches of the second or third-order, each subtended by a minute, short, tubular, triangular bract and bearing a 2-keeled bracteole; calyx tubular in proximal part, striate, with 3 triangular lobes; corolla split almost to the base into 3 triangular valvate lobes; stamens 6, borne at the base of the corolla lobes, filaments fleshy, elongate, inflexed at the tips, anthers oblong, medifixed, sagittate basally, latrorse; pistillode minute. Pollen spheroidal, bi-symmetric; monoporate with pore on one of two short axes of grain; ectexine tectate or semi-tectate, perforate-rugulate or foveolate-reticulate, aperture margin usually similar; infratectum columellate; longest axis 18–32 µm [2/3]. Pistillate flowers in dyads, each subtended by a small, triangular bract, and consisting of a pistillate and a sterile staminate flower and two 2-keeled cup-like bracteoles. Sterile staminate flower like the fertile but tending to be contorted by close-packing and with empty flattened anthers and a variable pistillode. Pistillate flowers larger than the staminate; calyx cupular, striate, lobes triangular, valvate; corolla split almost to the base into 3 triangular, valvate lobes; staminodes 6, epipetalous; gynoecium incompletely trilocular, triovulate, ovoid, scaly, stigmas 3, fleshy, rugose, divergent, ovule basally attached, anatropous. Fruit 1-seeded, globose or ovoid, beaked, stigmatic remains apical; epicarp covered in neat vertical rows of reflexed magenta to chestnut-coloured scales, mesocarp becoming thin and dry at maturity, endocarp not differentiated. Seed basally attached, sarcotesta thick, sweet, endosperm homogeneous; embryo basal. Germination adjacent-ligular; eophyll pinnate or with a single pair of divergent leaflets. Cytology not studied. (J. Dransfield & N. Uhl & C. Asmussen & W.J. Baker & M. Harley & C. Lewis, Genera Palmarum. The evolution and classification of palms. 2008)A

Relationships