Anatomical Studies of the Foliar Epidermis and Petiole of some Lannea Species in Jos, Plateau State, Nigeria

Aims: Leaf epidermal morphology and petiole anatomy of seven Lannea species namely; Lannea velutina, Lannea kerstingii, Lannea egregia, Lannea schimperii, Lannea acida, Lannea microcarpa, and Lannea edulis in Nigeria were investigated to provide new taxonomic characters that could help in proper identification and delimitation of the taxa. Place and Duration of Study: The study was carried out in the Department of Plant Science and Biotechnology, University of Jos, Nigeria between August 2020 and March 2021. Methodology: Transverse sections of petioles were cut using a rotary microtome and epidermal peels were made. Staining was done using Safranin and slides observed using a light microscope. Results: Stomatal distribution was hypostomatic except for L. velutina and L. edulis with amphistomatic distribution. Three stomata types are found; paracytic occurring in L. velutina, L. edulis and L. egregia, cyclocytic in L. schimperii and L. microcarpa and anomocytic in L. kerstingii and L. acida. Stomata index vary among taxa with L. egregia and L. acida having the highest (22.43%) and lowest (12.17%) respectively. The epidermal cell shape was polygonal in all the species and anticlinal wall patterns were straight to slightly curved. Unicellular/multicellular uniseriate trichomes were observed in L. schimperii, L. egregia and L. kerstingii distinguishing them from other species. Petiole outlines were circular to oval, epidermis was uniseriate and vascular bundles are collateral. Presence of continuous sclerenchyma rings surrounding the vascular bundles in L. kerstingii and L. microcarpa serve as a distinguishing character. Other distinguishing characters are presence of crystals, druses and phenolic idioblasts. A taxonomic key was produced using the anatomical character as an aid to the identification of the species. Conclusion: Variations observed in the stomata types, petiole outline, petiole vasculature type, trichome type and stomata index could be employed for species identification and delimitation.

Taxonomic studies of two trifoliate legumes of high economic importance in Ebonyi State, South-eastern Nigeria

Taxonomic studies of Sphenostylis stenocarpa and Centrosema pubescens based macro-morphology and foliar epidermises were carried out to determine their similarities and differences. The taxa are of high economic values as they are used as food and medicine in Nigeria. Standard methods were used to carry out the studies as qualitative and quantitative macromorphological characters of the taxa were obtained by visual observation and measuring with metre rule while foliar epidermal study followed standard methods previously used by other researchers. The taxa studied have trifoliate leaf type with leaf and leaflet arrangement alternate and opposite respectively. From the foliar epidermises, Sphenostylis stenocarpa possesses paracytic stomata on the abaxial surface and anisocytic stomata on the adaxial. The abaxial surface of Centrosema pubescens possesses anomocytic and paracytic stomata and anomocytic stomata on the adaxial surface. Cell shapes of the foliar epidermal surfaces are irregular with undulate anticlinal wall patterns except on the adaxial surface of Sphenostylis stenocarpa with pentagonal cell shape and straight anticlinal wall. The two taxa are similar in their leaf type and arrangement but differ greatly in their stomatal types.

Seed testa sculpture of species of Allium L. (Amaryllidaceae) and its taxonomic implications

We investigated the seed testa sculpture of twenty-four species belonging to thirteen sections and five subgenera of Allium from the herbarium materials or collected from plants in living collections. Seed testa sculpture of 21 species were described for the first time in this study. According to our results, the straight anticlinal wall and one large verruca or dense granules periclinal wall were found among the species in subgenus Amerallium, Cepa, Polyprason and Reticulatobulbosa. Only A. ochroleucum (sect. Daghestanica, subg. Polyprason) has U-type undulation anticlinal wall, which is similar to species of subg. Allium. The U- to Omega-type undulation anticlinal walls and several big verrucae with marginal verrucae periclinal wall were found in subg. Allium. Our results suggest that seed testa sculpture is important character of species and sections level of the genus Allium.

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

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.

Comparative foliar epidermal morphology of Isolona Engl. (Annonaceae)

A qualitative micromorphological assessment of the seven species of Isolona occurring in Nigeria and the Cameroons was undertaken with the aid of light microscope. The stomatal cells are particularly useful, providing stable characters which can be reliably employed in distinguishing the species. Hypostomatic leaves and paracytic stomatal type are generic constant. Possession of only paracytic stomata is characteristic of I. dewevrei whereas other species may have in addition another type such as 1+2 laterocytic stomatal type found only in I. zenkeri and presence of brachyparacytic stomata which shows relatedness of I. campanulata, I. congolana, I. hexaloba, I. pleurocarpus and I. thonneri. The epidermal surfaces appeared glabrous but an indication of hairs is shown by the presence of a glandular trichome base only in I. hexaloba. The epidermal cell characters such as epidermal cell shapes and anticlinal wall patterns seem to intergrade and they are not as definite as the stomatal cells. However, a combination of these features will be helpful in defining the species better and their leaf fragments can be differentiated based on the various characters studied for effective utilization in herbal medicinal research.

Leaf anatomical variation in Desmos Lour. and Dasymaschalon (Hook. f. & Thomson) Dalla Torre & Harms species (Annonaceae)

Nikmah IA, Rugayah R, Chikmawati T. 2020. Leaf anatomical variation in Desmos Lour. and Dasymaschalon (Hook. f. & Thomson) Dalla Torre & Harms species (Annonaceae). Biodiversitas 21: 3317-3330. The relationships between Desmos and Dasymaschalon are debated for along time. Those two genera have high morphological similarities, especially in their generative character (moniliform monocarps). Therefore, sterile specimens of Desmos are difficult to be distinguished from Dasymaschalon. Leaf anatomy in paradermal section of 20 taxa (12 species of Desmos, eight species of Dasymaschalon) have been carried out. The data were used to support the interspecific and intergeneric delimitation of Desmos and Dasymaschalon. Desmos and Dasymaschalon are two distinct genera mainly distinguished based on the anticlinal wall undulation of epidermal cells and supported by variation of the crystal type, and size. The anticlinal wall undulation of Desmos is almost straight to slightly wavy, and never sinuous, meanwhile, Dasymaschalon varies from almost straight to deeply sinusoid. The crystals of Desmos consist of rhombohedric, druse type A, and druse type B crystals, whereas Dasymaschalon has prism, druse type A, druse type B, and drue type C crystals.

Micromorphological, anatomical and molecular study of Hedera species (Araliaceae) in Iran

Hedera, with 12 extant species, is a genus of evergreen climbers native to Europe, north Africa, and south Asia. In this study, the micromorphological, anatomical structure and molecular evidences of 11 populations from two species of Hedera (H. helix and H. pastuchovii) have been considered to evaluate the relationships in Hedera. In total, seven quantitative and qualitative characters of pollen were selected and measured. Based on this study, the anticlinal wall and surface sculpturing of seed support for separation of two species of Hedera. Micromorphology of epidermis illustrated two types of epidermal cells: puzzle-shaped and polygonal cells. Using nuclear (nrDNA ITS) marker, we reconstructed phylogenetic relationships within two species of Hedera. This data set was analyzed by phylogenetic methods including Bayesian inference, maximum likelihood, and maximum parsimony. In phylogenetic analyses, all members of two species formed a well-supported clade (PP = 1; ML/BS = 100/100) and divided into two major clades (A and B). Neighbor Net diagram demonstrated separation of the studied populations. The results showed that these taxa differ in taxonomically important micromorphological, anatomical and molecular characteristics and these data provide reliable evidence for separation of these two species.

Taxonomic significance of some leaf anatomical features of the species of Annona L. (annonaceae) from Nigeria

A comparative study of the some leaf anatomical features of four species of Annona occurring in Nigerian was undertaken with the aid of light microscope. The four foliar structures (epidermis, petiole, midrib and lamina architecture) studied revealed useful characters which support recognition of the species. A combination of these features has been used to prepare an artificial indented dichotomous key for identifying the species. The generic constant features encountered included hypostomata, paracytic stomatal type, linear nerves endings, uneven midrib outline, and centrally located vascular bundles in the petiole and midrib. However, the most reliable distinguishing characters found across the species included presence of brachyparacytic stomata in A. reticulata, presence of trichomes on the midrib in A. senegalensis, absence of druses on the abaxial surface in A. muricata and A. squamosa, a thick pitted anticlinal walls on the surfaces of A. muricata and consistent polygonal areola shape in A. squamosa. The overlapping characters which also justify the closeness of the species and their grouping in a genus were recorded in both the qualitative and quantitative features. Prominent among them are the mean stomatal width which is about 1.0 μm in all species, nerve endings within the areole which varies between 1-2, U- or V-shaped midrib on the adaxial surface and straight to curved anticlinal wall pattern. The significance of these observations is discussed in updating the existing data in the genus. Keywords: Epidermis, Microscopy, Midrib, Petiole, Systematic

Morpho-anatomy of the cypselae of native species of Mutisieae (Asteraceae) from Mexico

The aims of this study were to describe and illustrate cypselae of 15 Mexican species of Mutisieae from observations using optical and scanning electron microscopy. The cypselae are heteromorphic with pilose, sericeous or glandular indumentum. The primary sculpture of the surface has two microstructural patterns: reticulate and plicate. The secondary sculpture is striate in 13 taxa, but in two species, Chaptalia estribensis and C. mexicana, differences were found in the secondary sculpture of the external and internal cypselae. The most distinctive anatomical trait is in the epicarp, which has rectangular or square-shaped cells that have a convex periclinal wall in most species of Chaptalia. The mesocarp has vascular bundles with fibers in all species of Chaptalia, but fibers are absent in Adenocaulon, Gerbera and Leibnitzia. In addition, the cells of the mesocarp inner layer have either thick walls or only an anticlinal wall in nine species of Chaptalia. The micromorphological characteristics of the primary or secondary sculpture of the surface, the type of trichomes and the variation they present have taxonomical value for recognizing closely-related taxa, whereas anatomical traits of the mesocarp distinguish Adenocaulon, Gerbera and Leibnitzia from most Chaptalia species.

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

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.