Itaya H.E.Moore, Principes 16: 85 (1972)

Primary tabs

http://media.e-taxonomy.eu/palmae/photos/palm_tc_103167_7.jpg

Distribution

Map uses TDWG level 3 distributions (http://www.nhm.ac.uk/hosted_sites/tdwg/geogrphy.html)
Brazil Northpresent (World Checklist of Arecaceae)B
Colombiapresent (World Checklist of Arecaceae)B
Ecuadorpresent (World Checklist of Arecaceae)B
Perupresent (World Checklist of Arecaceae)B
One species, known from a few localities in Amazonian Colombia, Ecuador, Peru and Brazil. (J. Dransfield & N. Uhl & C. Asmussen & W.J. Baker & M. Harley & C. Lewis, Genera Palmarum. The evolution and classification of palms. 2008)A

Discussion

  • Itaya appears to be most closely related to Chelyocarpus and Cryosophila. It differs, however, in the connation and adnation of sepals and petals, in its numerous stamens, in its unicarpellate gynoecium, and in the presence of two phloem strands in central vascular bundles of the petiole. The split in the petiole base has been commented on for Thrinax by Read (1975). It is an immediately recognizable field character but is not useful with herbarium material, which usually lacks leaf bases. (J. Dransfield & N. Uhl & C. Asmussen & W.J. Baker & M. Harley & C. Lewis, Genera Palmarum. The evolution and classification of palms. 2008)A

Diagnosis

  • Solitary moderate hermaphroditic fan palms of Amazonian rain forest, stems becoming bare; leaves are discolorous, with the blade divided by a central deep split and petiole base split; stamens are numerous and the fruit minutely roughened. (J. Dransfield & N. Uhl & C. Asmussen & W.J. Baker & M. Harley & C. Lewis, Genera Palmarum. The evolution and classification of palms. 2008)A

Biology And Ecology

  • Itaya amicorum occurs in rain forest at low elevations. (J. Dransfield & N. Uhl & C. Asmussen & W.J. Baker & M. Harley & C. Lewis, Genera Palmarum. The evolution and classification of palms. 2008)A

Common Name

  • Not recorded. (J. Dransfield & N. Uhl & C. Asmussen & W.J. Baker & M. Harley & C. Lewis, Genera Palmarum. The evolution and classification of palms. 2008)A

Etymology

  • Named after the River Itaya, a tributary of the Amazon near which the genus was discovered. (J. Dransfield & N. Uhl & C. Asmussen & W.J. Baker & M. Harley & C. Lewis, Genera Palmarum. The evolution and classification of palms. 2008)A

Uses

  • Itaya is a promising horticultural subject because of its large and handsome leaves much resembling those of Licuala species, its moderate stature, and creamy-white inflorescences and flowers. (J. Dransfield & N. Uhl & C. Asmussen & W.J. Baker & M. Harley & C. Lewis, Genera Palmarum. The evolution and classification of palms. 2008)A

Description

  • Moderate, solitary, unarmed, pleonanthic, hermaphroditic palm. Stem smooth (drying roughened), bare except for fibrous remains of sheaths and a lattice of long persistent, split petioles below the crown. Leaves spreading, induplicate, palmate; sheaths short, fibrous, split opposite the petiole, persisting as fibrous margins on the bases of the petioles; petiole elongate, unarmed, the base prominently split, channelled adaxially, rounded abaxially near the base, becoming biconvex and rhomboid in section distally, margins obtuse; adaxial hastula deltoid, often large, basally grooved, abaxial hastula narrow; blade held in one plane, thin, orbicular, divided to ca. 3/4 the radius at the middle, each half again deeply divided into several (4–7) elongate, wedge-shaped, 4–7-fold segments, these very shallowly divided apically into briefly bifid, 1-fold segments, abaxially lighter, midribs very prominent abaxially, transverse veinlets of 2 sizes very prominent. Inflorescences interfoliar, elongate, curved, branched to 3 orders basally, to 1 order distally; peduncle terete; prophyll short, 2-keeled, abaxially split, peduncular bracts ca. 5, bases tubular, apices inflated, acute, coriaceous, persistent, larger than the prophyll, marcescent, lightly tomentose, split on one side; rachis about as long as the peduncle, tapering, ± angled, tomentose; first-order branches each subtended by a persistent, marcescent bract similar to the peduncular bracts but progressively smaller and the upper-most scarcely tubular at the base, the branches ± flattened, adnate to the rachis often nearly to the succeeding bract; rachillae short, rather distant, slightly sinuous, each subtended by a linear acute bract, rachillae bearing spirally arranged, solitary flowers, each on a very short pedicel subtended by a small acute bract. Flowers creamy-white; sepals 3, connate in an acutely 3-lobed cup; petals 3, connate ca. 1/2 their length, the 3 lobes rounded and erect at anthesis, probably valvate in bud; stamens 18–24, one or two opposite each sepal, the remainder opposite the petals, filaments connate basally in a fleshy tube less than 1/2 their length, slightly adnate to corolla basally, fleshy and ± awl-shaped distally, anthers exserted at anthesis, oblong, dorsifixed at the middle, versatile, bifid at apex and base, latrorse; gynoecium of 1 carpel, eccentrically ovoid, narrowed to a slender curved style and oblique papillose stigma, ovule hemianatropous, attached adaxially at the base, the short funicle bearing a large oblique aril. Pollen ellipsoidal, with slight to obvious asymmetry; aperture a distal sulcus; ectexine tectate, coarsely perforate, aperture margin finely perforate; infratectum columellate; longest axis 36–41 µm [1/1]. Fruit oblong-ovoid or subglobose with eccentrically apical stigmatic remains; epicarp minutely granular-roughened and with minute perforations, mesocarp thick, white, dry, with anastamosing fibres and a peripheral layer of sclerosomes, endocarp not differentiated. Seed oblong-ovoid, hilum elliptic, subbasal, raphe branches ascending-spreading, endosperm homogeneous; embryo eccentrically basal. Germination remote-tubular (Chavez 2003); eophyll undivided, elliptic. Cytology: 2n = 36. (J. Dransfield & N. Uhl & C. Asmussen & W.J. Baker & M. Harley & C. Lewis, Genera Palmarum. The evolution and classification of palms. 2008)A

Anatomy

  • Leaf (Uhl 1972c), roots (Seubert 1997), floral (Uhl 1972b). (J. Dransfield & N. Uhl & C. Asmussen & W.J. Baker & M. Harley & C. Lewis, Genera Palmarum. The evolution and classification of palms. 2008)A

Fossil record

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

Relationships

  • Roncal et al. (2008) resolve Itaya as sister to all Cryosophileae except Chelyocarpus with low support. (J. Dransfield & N. Uhl & C. Asmussen & W.J. Baker & M. Harley & C. Lewis, Genera Palmarum. The evolution and classification of palms. 2008)A

Taxonomic accounts

  • Moore (1972). (J. Dransfield & N. Uhl & C. Asmussen & W.J. Baker & M. Harley & C. Lewis, Genera Palmarum. The evolution and classification of palms. 2008)A

Bibliography

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