Leaf epidermal descriptors applied to the taxonomy of Lauraceae, including new anatomical characters

Abstract

The difficulty of identifying Lauraceae species is well known. The leaf epidermis of 18 species from the Federal District, Brazil, was analyzed to test more characters as an aid to the taxonomy of this family. New anatomical characters are proposed here, such as sinus number, internal angles and number of sides of the common epidermal cells, their arrangement around the trichome base, and the shape and width of the subsidiary cells in relation to the guard cells. Epidermal characters that can aid in the identification of the studied species are: the contour of the common cells on both leaf surfaces and their anticlinal wall width, number of sides of the polygonal cells, sinus number, presence of angles greater than 180°, presence and type of indumentum, common cells with radial arrangement around the trichome base, stomatal position relative to the rest of the epidermis and width of the subsidiary cells in relation to the guard cells. Glabrous and glabrescent leaves are distinguished. Two species have unique characters: Aniba heringeri, with papillae on the abaxial surface, and Cryptocarya moschata, with peculiar horseshoe-shaped subsidiary cells. Characters of the epidermis together with the external leaf morphology are sufficient to distinguish the studied species. Additionally, we report for the first time the occurrence of Mezilaurus crassiramea and Ocotea diospyrifolia for the flora of Federal District, Brazil.

Microscopic investigations of Ocotea paranaensis―A Brazilian endemic and endangered species

“…They are paracytic type and located at the same level as the adjacent epidermal cells. Paracytic type and hypostomatic leaves are frequently observed in Ocotea species (Betim et al, 2020;Brustulim et al, 2020;Farago et al, 2005;Gomes-Bezerra et al, 2018;Gonçalves et al, 2018). Trofimov and Rohwer (2018) Simple non-glandular trichomes were found in O. paranaensis, as also observed in some other Ocotea species (Brustulim et al, 2020;Ceolin et al, 2009;Farago et al, 2005;Gonçalves et al, 2018).…”

“…They are paracytic type and located at the same level as the adjacent epidermal cells. Paracytic type and hypostomatic leaves are frequently observed in Ocotea species (Betim et al, 2020; Brustulim et al, 2020; Coutinho, Agra, Barbosa‐Filho, & Basilio, 2006; Farago et al, 2005; Gomes‐Bezerra et al, 2018; Gonçalves et al, 2018). Trofimov and Rohwer (2018) classified the stomatal shapes in Ocotea species and observed elliptic shapes in O. cernua (Nees) Mez, O. guianensis Aubl.…”

“…In Lauraceae, the anticlinal cell walls can be curved, undulate, sinuate, straight, or Ω‐shaped (Trofimov & Rohwer, 2018, 2020). In Ocotea , the shapes of the anticlinal cell walls are valuable features in distinguishing species (Betim et al, 2020; Gomes‐Bezerra et al, 2018; Trofimov & Rohwer, 2018, 2020).…”

A comparative phytochemical study of nine Lauraceae species by using chemometric data analysis

“…Although phytochemical studies are recognized for being able to deepen the understanding of relationships among targeted plants, comparative chemical analyses among Lauraceae have not been performed [4,5]. Many taxonomic analyses for Lauraceae species have been conducted on using morphological [6,7], anatomical [8][9][10][11], and genetic [12][13][14] differences to distinguish species.…”