Data from: Of puzzles and pavements: a quantitative exploration of leaf epidermal cell shape

Epidermal cells of leaves are diverse: tabular pavement cells, trichomes,
and stomatal complexes. Pavement cells from the monocot Zea mays (maize)
and the eudicot Arabidopsis thaliana (Arabidopsis) have highly undulate
anticlinal walls. The molecular basis for generating these undulating
margins has been extensively investigated in these species. This has led
to two assumptions: first, that particular plant lineages are
characterized by particular pavement cell shapes; and second, that
undulatory cell shapes are common enough to be model shapes. To test these
assumptions, we quantified pavement cell shape in epidermides from the
leaves of 278 vascular plant taxa. We found that monocot pavement cells
tended to have weakly undulating margins, fern cells had strongly
undulating margins, and eudicot cells showed no particular undulation
degree. Cells with highly undulating margins, like those of Arabidopsis
and maize, were in the minority. We also found a trend towards more
undulating cell margins on abaxial leaf surfaces; and that highly
elongated leaves in ferns, monocots and gymnosperms tended to have highly
elongated cells. Our results reveal the diversity of pavement cell shapes,
and lays the quantitative groundwork for testing hypotheses about pavement
cell form and function within a phylogenetic context.