Drymophloeus Zipp., Alg. Konst- Lett.-Bode 1: 297 (1829)

Primary tabs

http://media.e-taxonomy.eu/palmae/photos/palm_tc_64732_5.jpg

Number of Taxa

  • 3 species

Discussion

  • Zona (1999a) demonstrated good evidence for removing Drymophloeus samoensis and returning it to the genus Solfia and some evidence for dividing the genus into two groups: undergrowth species (Drymophloeus) and emergent species (Rehderophoenix). However, Drymophloeus in the broader sense is retained here. Zona (1999a) suggested that Drymophloeus is closely related to Brassiophoenix, Balaka and Solfia, with Balaka as the sister genus. (J. Dransfield, N. Uhl, C. Asmussen, W.J. Baker, M. Harley and C. Lewis. 2008)

Biology And Ecology

Etymology

Diagnosis

Description

  • Small to moderate, solitary or rarely weakly clustering, unarmed, pleonanthic, monoecious palms. Stem erect, slender, ringed with rather widely spaced leaf scars, sometimes short stilt roots present basally. Leaves pinnate, arching slightly, few in crown; sheath rather thick, forming a slender crownshaft, glabrous adaxially, abaxially densely covered with whitish tomentum and small red-brown scales, becoming minutely brown-dotted; petiole absent or short, slender, adaxially deeply channelled, abaxially rounded, covered with deciduous tomentum and pale or dark scales; rachis long, slender, adaxially often sharply pointed or ridged and rounded, abaxially rounded, densely covered with brown tattered scales or tomentum; leaflets subopposite to alternate, in one plane, single-fold, broadly or narrowly wedge-shaped, or broadly lanceolate to narrowly obovate, distal pair sometimes broader and united or small and narrow, leaflets distally variously lobed or oblique, raggedly praemorse, adaxially glabrous except for a few scales near bases of major veins, abaxially densely covered with small scales on minor veins, major veins with ramenta toward the base, or lacking scales except on midrib, midvein and a pair of large veins along or close to the margins prominent, margins densely covered with caducous tomentum and scales, transverse veinlets not evident. Inflorescences infrafoliar, branched to 1 or basally to 2–3 orders, protandrous; peduncle relatively slender, elongate (except Drymophloeus subdistichus), elliptical in cross-section; prophyll deciduous, tubular, slender, dorsiventally flattened, with 2, narrow, lateral keels, pointed, splitting apically and for a short distance abaxially to release the peduncular bract, densely covered with multibranched or pale-margined brown scales; peduncular bract tubular, slender, much longer than the prophyll, with a long rather flat, pointed tip, densely covered with scales like the prophyll, a few small incomplete peduncular bracts sometimes also present; rachis shorter than the peduncle, angled, tapering, bearing rather few, distant, spirally arranged branches; rachis bracts low, rounded; rachillae short, tapering, bearing spirally arranged triads of flowers basally, and pairs of a pistillate and one staminate, or a single staminate flower distally; floral bracteoles low, rounded or truncate. Staminate flowers borne laterally toward the lower side of the pistillate flower in rounded indentations in the rachillae; sepals 3, distinct, imbricate, irregularly but strongly keeled, margins thin, variously notched; petals 3, distinct, ovate, valvate, evenly thickened, adaxially grooved, reflexed at anthesis; stamens numerous, 24 to more than 320, filaments moderate, awl-shaped, anthers elongate, sagittate basally, uneven, sometimes divided apically, medifixed, versatile, latrorse; pistillode with 3 short, rounded, 3-angled lobes or ovoid attenuate to 2/3 as long as the stamens, usually shortly trifid apically. Pollen ellipsoidal or oblate triangular, asymmetric to pyriform; aperture a distal sulcus or trichotomosulcus; ectexine tectate, perforate or perforate-reticulate, aperture margin similar or slightly finer; infratectum columellate; longest axis ranging from 50–63 µm [2/7]. Pistillate flowers broadly ovoid; sepals 3, distinct, imbricate, hooded, edges minutely toothed or variously notched; petals 3, twice as long as the sepals in late bud, distinct, ovate, imbricate, lateral margins shortly fringed, tips thick, valvate; staminodes 3, shortly joined basally, wide, truncate and bifid or uneven distally; gynoecium symmetrical, ovoid, tapering distally, unilocular, uniovulate, stigmas 3, recurved, ovule attached laterally or pendulous from the top of the locule, form unknown. Fruit fusiform to ovoid, red at maturity, stigmatic remains apical; epicarp thin, smooth, becoming pebbled when dry, mesocarp fleshy, fibrous, with stinging crystals, fibres adherent to the thin, rather smooth endocarp, endocarp usually circular in cross-section, 5-lobed in D. hentyi and D. subdistichus). Seed ovoid, surface smooth, hilum apical, raphe much branched, branches somewhat sunken, endosperm homogeneous or ruminate; embryo basal. Germination adjacent-ligular; eophyll bifid, or entire, ovate, margins toothed. Cytology: 2n = 32. (J. Dransfield, N. Uhl, C. Asmussen, W.J. Baker, M. Harley and C. Lewis. 2008)

Anatomy

Relationships

  • Lewis et al. (in prep.) resolved Drymophloeus as polyphyletic. Drymophloeus litigiosus and D. oliviformis are resolved in a clade with Normanbya, Carpentaria and Wodyetia with low support. Drymophloeus hentyi is resolved as sister to Ponapea with high support. Norup et al. (2006) resolve a clade with low support comprising D. litigiosus and Normanbya. (J. Dransfield, N. Uhl, C. Asmussen, W.J. Baker, M. Harley and C. Lewis. 2008)

Uses

Bibliography

  • Dransfield, J. , Uhl, N. , Asmussen, C. , Baker, W.J. , Harley, M. & Lewis, C. 2008. Genera Palmarum. The evolution and classification of palms. Kew Publishing, Royal Botanic Gardens Kew.