Phylogenetic signal (K) of leaf attributes and stomatal traits in 17 Paphiopedilum species.

K K >1 show that close relatives are more similar than expected. SL, stomatal length; SW, stomatal width; SA, stomatal area; SD, stomatal density; SI, stomatal index; UET, upper epidermal thickness; UCT, upper cuticular thickness; PTT, palisade tissue thickness; STT, spongy tissue thickness; LET, lower epidermal thickness; LCT, lower cuticular thickness, MT, mesophyll thickness; LT, leaf thickness; TCT, total cuticular thickness; LMA, leaf mass per unit area; LA, leaf area; and VD, vein density.