2001/01/01 by Sherwin Carlquist, Edward L. Schneider · 36 citations
Agricultural and Biological Sciences · Biochemistry, Genetics and Molecular Biology · #Plant Diversity and Evolution #Plant and Fungal Species Descriptions #Plant Parasitism and Resistance #Xylem #Biology #Tracheid #Anatomy #Botany #Whorl (mollusc) #Genus
paper · open access · doi:10.1353/psc.2001.0020
published in Pacific Science 55(3), 305-312 (University of Hawaii Press)
openalex publication_date 2001/01/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/02
Light microscopy was used to study leaf hypodermis, vein sclerenchyma, stomatal subsidiary cell types, and stem and root xylem in liquid-preserved material of Amborella trichopoda; oblique borders on tracheid pits, scalariform end walls on tracheids, and porosities in end-wall pit membranes were studied with scanning electron microscopy. Amborella shares stomatal configurations, nodal type (in part), ray types, and porose pit membranes in tracheary elements with llliciaies s.l., but differs from that order in lacking oil cells, vessels, and grouped axial parenchyma cells. These data are consistent with a basal position in angiosperms for Amborella, and for a close relationship with, but not inclusion in, llliciales; inclusion in a monofamilial order is conceivable. Both loss of pit membranes or pit membrane portions on end walls and increase in cell diameter are requisites for origin of vessels. Sarcandra and Illiciaceae show these early stages in origin of vessels; Amborella shows development of porosities in pit membranes. Vessel presence or absence may not be strictly bipolar, because some primitive vessel elements exhibit at least some tracheidlike characteristics and are thus transitional, and because changes in at least two characters define vessel origin.