Leaf epidermal micromorphology defining the clades in Cinnamomum (Lauraceae)

By

Zeng, Gang
Liu, Bing (Botanist)
Rohwer, J. G. (Jens G.), 1958-
Ferguson, David Kay, 1942-
Yang, Yong

Type

Article

Date of Publication

2021

Original Publication

PhytoKeys

Volume

182

Pages

125--148

Subjects

Anatomy , Cinnamomum , Lauraceae , scanning electron microscope (SEM) , systematics

Contributed by

Pensoft Publishers

Language

English

Published by

Sofia, Bulgaria Pensoft Publishers [2010]-

Identifiers

DOI: https://doi.org/10.3897/phytokeys.182.67289

 

Abstract

In this study, we sampled 48 species of AsianCinnamomumcovering the species groups that were identified in recent phylogenetic studies and conducted leaf micromorphological observations using both light microscopy (LM) and scanning electron microscopy (SEM). Synapomorphies were determined by means of mapping micromorphological characters on a phylogenetic tree. The results indicate thatCinnamomumexhibits two different types of leaf upper epidermis: Type I has smooth/non-reticulate periclinal walls whereas Type II has reticulate periclinal walls and is unusual in the family Lauraceae. We found that the two types of micromorphological characters are clade-specific, sect. Camphora s.s. possesses Type I leaf upper epidermis, and sect. Cinnamomum s.l. has Type II leaf upper epidermis. Our study also reveals thatC. saxatile, a member of sect. Camphora s.l. in the traditional classification, actually has Type II leaf upper epidermis, thus reinforcing the result of a recent molecular phylogeny that has this species in a clade consisting mainly of species of sect. Cinnamomum.