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Comparative floral structure and systematics of Pelagodoxa and Sommieria (Arecaceae) 总被引:1,自引:0,他引:1
FRED W. STAUFFER WILLIAM J. BAKER JOHN DRANSFIELD PETER K. ENDRESS 《Botanical journal of the Linnean Society. Linnean Society of London》2004,146(1):27-39
Floral structure is compared in Pelagodoxa and Sommieria (Arecaceae, Arecoideae). Male flowers have three free, imbricate sepals, three basally congenitally united and apically valvate petals, and six stamens. Anthers are dorsifixed and dehiscence introrse. The sterile gynoecium is tricarpellate. Female flowers have three free, imbricate sepals and three free, imbricate petals, which are slightly fused with the sepals at the base. Four to six staminodes are congenitally united at the base and fused with the ovary for a short distance. The gynoecium is syncarpous. Carpels are almost equal in early development; later the gynoecium becomes pseudomonomerous. The three stigmatic branches are equally developed, apical and sessile. The carpels are (syn-)ascidiate up to the level of the placenta and (sym-)plicate above. Each carpel has one ovule, in the sterile carpels it is aborted at anthesis. The fertile ovule is erect up to anthesis and pendant afterwards because of the bulging out of the ovary. Pollen tube transmitting tracts (PTTT) encompass the secretory epidermis of the ventral slits of each carpel. Floral structure in Pelagodoxa and Sommieria supports the sister group relationship between the two genera suggested in recent molecular phylogenies and reflects their close relationships to a major clade of pseudomonomerous arecoid palms from the Indo-Pacific region. © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 27–39. 相似文献
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This study represents a preliminary sampling of the pericarp histology of the subtribe Iguanurinae (tribe Areceae, subfamily
Arecoideae) of the family Arecaceae. At least one sample from each of the 27 recognized genera was examined and illustrated
with a line drawing. This sampling serves to characterize fruit structure in the subtribe as a whole, to illustrate the diversity
of pericarp adaptations found in the subtribe, to characterize the monotypic genera, to provide hypotheses about the characterization
of the larger genera, and to test existing phylogenetic hypotheses about the Iguanurinae. There are no unique tissues present
in the pericarp in this subtribe, but genera can be readily characterized by unique combinations and distributional patterns
in common tissues. These patterns, and some prominent evolutionary trends, parallel those in related subtribes of Areceae,
such as the Ptychospermatinae and Arecinae. Significant in this subtribe is variation in the distribution of tanniniferous
cells, raphide-bearing cells and brachysclereids, in the sculpturing of the seed and the locular epidermis, in the thickness
of the locular epidermis, in the thickness of the fibrous vascular bundle sheaths, and especially in the number, orientation
and distribution of nonvascular fibrous bundles. One major trend is the formation of systems of separate fibrous bundles and
their progressive displacement toward the outer layer of the fruit, where a complex exocarp may form. The diversity of pericarp
structure in the Iguanurinae is far greater than in the two subtribes previously studied. 相似文献
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