Comparative anatomy of five species of Campyloneurum (Polypodiaceae) from South America

Anatomical characters of the sporophyte of five Campyloneurum species are presented: C. aglaolepis, C. angustifolium, C. angustipaletum, C. lorentzii, and C. tucumanense, to evaluate anatomical characters with a taxonomic value. Histological sections of the root, rhizome, and petiole were made in three sections (basal, middle, and distal) and lamina, using specimens of herbarium and material collected for this purpose. Observations were made with a light microscope and a scanning electron microscope. The anatomical characters, such as the type of helical thickening in parenchymal cells in outer cortex and the number of layers in the inner cortex of the root; diameter, presence of prurine, number of meristeles and sclereid nests in the rhizome; adaxial groove and the number of vascular bundles in the petiole; and mesophyll, stomata and hairs types in the lamina, shows a highly significant in taxonomic value for the separation between the five studied species. For the first time, hydathodes, nectaries, diacytic stomatal types and homogeneous mesophyll are described in Campyloneurum, and the anatomy of C. tucumanense is presented.

Automated summary

The anatomical features of the sporophyte of five Campyloneurum species were studied, revealing significant differences in anatomical characteristics that hold taxonomic value. This study provided insights into the unique anatomical traits of these species, contributing to a better understanding of their taxonomic classification.