Leaflet blade epidermis and its taxonomic significance in 13 species of Bignonieae (Bignoniaceae) from Pico do Jabre, Paraíba, northeast of Brazil

Abstract

Bignonieae is the largest tribe of Bignoniaceae, with 21 genera and 393 species of lianas and shrubs, 2–3-foliolate with the terminal leaflet modified as tendrils. We examined the micromorphologies of the leaflet blade epidermises of 13 species of Bignonieae belonging to Amphilophium, Anemopaegma, Bignonia, Cuspidaria, Dolichandra, Fridericia, Pyrostegia, Tanaecium, and Xylophragma, from Pico do Jabre, Paraíba, Brazil. These are lianas except for Tanaecium parviflorum (shrubby). We sought to identify epidermal leaflet parameters to support their taxonomy subject to great similarities between their vegetative characters, mainly in species of the same genus and related genera. Analyses were performed using light and scanning electron microscopy, and showed five types of epicuticular waxes, four cuticle types, three epidermal cell anticlinal wall types, and non-glandular and glandular trichomes. Hypostomatic leaves showed ten different types of stomata, with stomatal indices from 6.21% (Bignonia ramentacea) to 23.52% (Tanaecium parviflorum) and stomatal densities from 76 stomata/mm² (Pyrostegia venusta) to 752.9 (T. parviflorum). The presence of raphides in Amphilophium crucigerum and styloids in Fridericia pubescens constitute the first records for these genera. Epidermal micromorphology provided a set of distinctive characters to separate these species, representing an additional tool to support their taxonomies, as well as that of tribe Bignonieae.

Leaf and stem micromorphology of Jacquemontia evolvuloides (Moric.) Meisn. (Convolvulaceae) populations: New insights for taxonomic classification using light and scanning electron microscopy

“…Anatomical characters are important for classifying and delimiting angiosperm species (Farias et al, 2016; Gomes et al, 2005; Lopes‐Silva et al, 2021; Metcalfe & Chalk, 1950). Microscopic techniques, including light (LM) and scanning electron microscopy (SEM) have provided fundamental information for delimiting different groups of plants (Shah et al, 2018; Silva et al, 2020; Ullah et al, 2019).…”

A new Jacquemontia Choisy (Convolvulaceae) species from the Brazilian Amazon forest

“…Anatomical studies have been very relevant in the classification and delimitation of angiosperm species (Gomes et al 2005;Farias et al 2016;Lopes-Silva et al 2021). Among anatomical characters, several authors have indicated the shape of the petiole and midrib, the presence and types of stomata, as well as the morphology of the epidermis as taxonomically relevant characters (Rashid and Parnell 2017;Song and Hong 2018;Alencar et al 2022;Belo et al 2023a).…”