Foliar epidermal morphology of the genera Aneilema and Commelina (Commelinaceae)

Abstract

A Comparative study of the foliar epidermal morphology of some members of the genera Commelina and
Aneilema was undertaken. The aim was to study the structure of the foliar epidermis of five species  belonging to the two genera and thus provide anatomical information that will help to possibly eliminate identification problems that exist among species of the genera using diagnostic characters of the foliar  epidermal morphology. Epidermal peels of both the adaxial and abaxial surfaces of members of the genera were made using standard method and photomicrographs of the surfaces were made. Qualitative and quantitative characters were observed, measured and recorded. Results show that the preponderance of hexacytic stomata is classificatory of the two genera. Rectangular to polygonal epidermal cells on the adaxial lamina is diagnostic of Aneilema aequinoctiale. Result also reveals that simple hooked bicellular and unicellular non glandular trichome is diagnostic of Commelina benghalensis and Aneilema  aequinoctiale respectively. Similarities exist in foliar epidermal characters like the trichome and stomata types among other characters between the genera Commelina and Aneilema. The low level of variability in the foliar epidermal morphology of the taxa studied show that foliar epidermal characters cannot stand alone in the separation of the taxa but need to be combined with characters from other lines of evidence.

Key words: Aneilema, Delimitation, Subtropical, Systematics, Trichome