Anatomy and microscopy of Piper caldense, a folk medicinal plant from Brazil

ABSTRACT

ABSTRACT Piper caldense C. DC., Piperaceae, commonly known as "pimenta-d'água", "pimenta-darda" or "paguarandy" in Brazil, is a shrub that grows mainly in humid and shaded habitats. The present study investigates the anatomy of the leaves and stems of P. caldense by light and scanning electron microscopy in order to provide supporting data for correct identification of the species. The leaves are hypostomatic, have a 2-layered hypodermis, and posses pearl glands. The midrib shows a 'U'-shaped stele comprised of about ten collateral vascular bundles. The main anatomical marker of the stem is the presence of a continuous sclerenchymatous sheath in the pith. Two forms of calcium oxalate crystals, namely crystal sand and raphides, are observed in this species.