Systematic significance of the leaf cuticle of Hypodaphnis zenkeri (Engl.) Stapf (Lauraceae) and a record of its volatile organic compounds

Abstract

Hypodaphnis zenkeri is a monotypic taxon whose position is basal in the phylogenetic tree of the family Lauraceae. Cuticular information on the plant is lacking. Given the systematic relevance of this character in the family and absence of its record for the species, the leaves of the species were investigated with the aid of light and scanning electron microscopy. Also, volatile organic compounds in leaves and fruits were studied with Gas Chromatography-Mass Spectrometry (GC-MS), for the first time. Taxonomically useful cuticular features of the species include long stomatal rim and aperture, granulated periclinal walls on the adaxial surface and superficial stomatal orientation. The leaves and fruits of the plant are rich in volatile organic compounds such as 1,2-benzene-dicarboxylic acid, hexadecanoic acid ester and stigmasta-3,5-diene. Based on these features, the species can be distinguished from other related taxa in the family.