Pseudophoenix H.Wendl. ex Sarg., Bot. Gaz. 11: 314 (1886)

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Number of Taxa

  • 4 species

Discussion

  • Pseudophoenix stands apart as the only genus of the Ceroxyloideae having hermaphroditic flowers and a well-developed crownshaft. It has unique anatomical features of the leaf and attachment of the anther, as well as an unusually elongate base or pseudopedicel on the flower. The spirally arranged single flowers on a highly branched interfoliar inflorescence, certain anatomical features, and the presence of just one single phloem strand in the central vascular bundles of the petiole ally Pseudophoenix with the Ceroxyleae. (J. Dransfield, N. Uhl, C. Asmussen, W.J. Baker, M. Harley and C. Lewis. 2008)

Biology And Ecology

Etymology

Diagnosis

  • Relatively short stemmed pinnate-leaved Caribbean tree palms, often with bottle-like trunks; crownshaft present; flowers are hermaphroditic or occasionally unisexual towards the tips of the rachillae and the ovary with three locules and three ovules. The fruit is lobed when more than one seed develops. (J. Dransfield, N. Uhl, C. Asmussen, W.J. Baker, M. Harley and C. Lewis. 2008)

Description

  • Moderate, solitary, pleonanthic, polygamous or hermaphroditic palms. Stem erect, often swollen, prominently ringed with rather wide leaf scars, smooth to finely striate, grey or green, waxy. Leaves few, mostly ca. 10, reduplicately pinnate, deciduous by a basal abscision zone; sheath forming a short, somewhat swollen crownshaft, splitting distally opposite the petiole, waxy; petiole channelled adaxially, rounded abaxially; rachis flat to angled adaxially, rounded abaxially, ± glabrous; leaflets numerous, irregularly arranged, grouped and fanned within the groups, stiff, acute, single-fold, waxy on both surfaces, midribs evident, other veins small, transverse veinlets not evident. Inflorescences interfoliar, pendulous or arched, branched to the fifth order; peduncle elongate, dorsiventrally flattened; prophyll tubular, 2-keeled, flattened, leathery, persistent, opening at the apex; peduncular bracts 2, the first similar to the prophyll, the second usually collar-like; rachis longer than or about as long as the peduncle; rachillae stiffly spreading or pendulous, each subtended by a small open bract. Flowers borne singly, spirally arranged, each subtended by an acuminate bract, hermaphoditic proximally but the distal few staminate with a much reduced pistil, base of the flower extended in a pseudopedicel formed by fusion and elongation of the receptacle and the base of the calyx; calyx 3-lobed with rounded, apiculate tips; petals 3, valvate, thick, much longer than the calyx, basally connate in a very short tube; stamens 6, filaments thin, dilated and briefly connate in a ring basally, the apex lying in a groove in the abaxial surface of the anther to about the midpoint of the connective, then bent sharply inward, anthers large, elongate, ± pointed apically and basally, dorsifixed, latrorse; gynoecium conical, trilocular, tri-ovulate, with 3 glands at the base opposite the petals, stigmas sessile, very short, becoming recurved after fertilisation, ovules campylotropous, inserted on the adaxial side of the locule. Pollen ellipsoidal, usually more or less bi-symmetric; aperture a distal sulcus; ectexine tectate, foveolate or reticulate, aperture margin and proximal face similar, but lumina smaller; infratectum columellate; longest axis ranging from 43–55 µm [3/4]. Fruit 1–3-seeded, waxy red, globose or 2–3-lobed, stigmatic remains near the base or in a central depression in 3-seeded fruits; epicarp smooth, mesocarp fleshy, with raphides, lacking fibres, endocarp hard, brown, smooth. Seed not adherent to endocarp at maturity, hilum basal, raphe branches ascending and spreading in shallow grooves, endosperm homogeneous; embryo subbasal. Germination remote-tubular; eophyll narrow lanceolate. Cytology: 2n = 34. (J. Dransfield, N. Uhl, C. Asmussen, W.J. Baker, M. Harley and C. Lewis. 2008)

Anatomy

  • Leaf and floral (Read 1968), and root (Seubert 1996b). The vascular system of the carpel, which consists of three major bundles with ventral bundles in ‘lateral’ positions and an ovular supply associated with ventral bundles only, resembles that of ceroxyloid and chamaedoreoid palms. The ground tissue of the gynoecium, which lacks tannins but has abundant raphides, is like that of Chamaedorea (Read 1968, Uhl and Moore 1971). (J. Dransfield, N. Uhl, C. Asmussen, W.J. Baker, M. Harley and C. Lewis. 2008)

Relationships

Taxonomic accounts

Fossil record

  • Reticulate trichotomosulcate pollen from the Lower Eocene of Saudi Arabia is compared erroneously with Pseudophoenix pollen (Srivastava and Binda 1991). Reticulate monosulcate palm-like pollen, Liliacidites tritus Frederiksen, from the Upper Eocene (Upper Jacksonian) of Texas, is also suggested to have an affinity with Pseudophoenix (Frederiksen 1980, 1981). Although geographically less persuasive, this fossil is probably more like the reticulate pollen of Ceroxylon. (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.