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Item Morphoanatomy of nectaries of Chamaecrista (L.) Moench sections Chamaecrista, Caliciopsis and Xerocalyx (Leguminosae: Caesalpinioideae)(Acta Botanica Brasilica, 2017-07) Silva, Marinalva dos Santos; Coutinho, Ítalo Antônio Cotta; Araújo, Maicon Nascimento; Meira, Renata Maria Strozi AlvesNectaries are specialized structures that secrete nectar. Several species of Chamaecrista possess nectaries on the petiole, which have been shown to vary widely in morphology and the chemical nature of their secretion. However, a comprehensive investigation of the nectaries of the clade formed by sect. Chamaecrista, Caliciopsis and Xerocalyx has yet to be performed. Our study aimed to confirm whether or not the leaf glands of species of this clade are in fact nectaries, determine the chemical nature of their secretion and expand the morphoanatomical database on leaf nectaries in Chamaecrista with the intention of contributing to the taxonomy and phylogeny of the genus. Samples from herbarium and field-collected material were subjected to standard methods for light and scanning electron microscopy. Four different forms of nectaries were observed: urceolate, patelliform, verruciform and cupuliform. The nectaries were found to comprise a single-layered epidermis, nectary parenchyma, subnectary parenchyma and vascularization. Polysaccharides, lipids, phenolic compounds and proteins were detected in secretions. Although anatomical similarities were observed among the studied species, their morphology differed. Moreover, the glands are indeed nectaries and are similar to those observed in other species of the genus Chamaecrista. These data hold potential taxonomic usefulness for the studied sections.Item Colleters in Chamaecrista (L.) Moench sect. Chamaecrista and sect. Caliciopsis (Leguminosae-Caesalpinioideae): anatomy and taxonomic implications(Acta Botanica Brasilica, 2017-07) Silva, Marinalva dos Santos; Coutinho, Ítalo Antônio Cotta; Araújo, Maicon Nascimento; Meira, Renata Maria Strozi AlvesThe genus Chamaecrista contains ca. 330 species organized into six sections, of which section Chamaecrista is the second largest (ca.75 species) distributed among six series, while the section Caliciopsis contains only two species. Colleters have been described in the genus Chamaecrista and they show potential taxonomic and phylogenetic significance. They are associated with lubrication, desiccation prevention and protection from microbial attacks of young developing organs. Although six types of colleters have been described for the genus Chamaecrista, there have been no studies focusing on the diversity of colleters in the sections Chamaecrista and Caliciopsis. Samples from developing leaves and flowers of both sections were obtained from herbarium and field collections and subjected to standard methodologies for both light and scanning electron microscopy. Histochemical tests were also performed to determine the nature of the exudates. Five types of non-vascularized colleters were found: short digitiform, long digitiform, club-shaped, pyriform and short bottle-shaped. Polysaccharides, pectins, lipids and proteins were detected in the exudates of all types of colleters. Among the five types of colleters observed, pyriform is a novelty for Chamaecrista, reinforcing the significant morphological diversity of these secretory structures in this genus.Item A study of the morphoanatomical characters of the leaves of Chamaecrista (L.) Moench sect. Apoucouita (Leguminosae-Caesalpinioideae)(Acta Botanica Brasilica, 2013-04) Coutinho, Ítalo Antônio Cotta; Rando, Juliana Gastaldello; Conceição, Adilva de Souza; Meira, Renata Maria Strozi AlvesLittle attention has been paid to species of Chamaecrista sect. Apoucouita (Leguminosae-Caesalpinioideae), especially regarding anatomical studies. When only vegetative material is available, the identification of such species may be difficult. Additionally, vegetative material of some species of C. sect. Apoucouita may be even harder to identify because they can resemble species of Inga Mill. (Leguminosae-Mimosoideae). The present study focused on recognizing morphoanatomical characters of leaves that are taxonomically useful for the species of C. sect. Apoucouita by employing standard anatomical techniques. The arrangement of the vascular system in the petiole/rachis, dorsiventral mesophyll, mucilage idioblasts in the epidermis of leaflets and hypostomatic leaves were some of the characters shared by all species studied. Length of the petiole, position and type of extrafloral nectaries, leaflet venation, presence and type of papillae on the epidermis of the leaflet blades and sclereids in the mesophyll were some of the characters useful in the distinction of taxa. The vascular arrangement of the petiole/rachis is a promising character in the distinction of species of C. sect. Apoucouita and Inga. Based on morphoanatomical data, the taxonomic revision of some species and varieties ascribed to C. sect. Apoucouita is suggested.Item Anatomical characteristics as taxonomic tools for the species of Curtia and Hockinia (Saccifolieae–Gentianaceae Juss.)(Plant Systematics and Evolution, 2013-06-25) Dalvi, Valdnéa Casagrande; Meira, Renata Maria Strozi Alves; Francino, Dayana Maria Teodoro; Silva, Luzimar Campos; Azevedo, Aristéa AlvesThe delimitation of species and even support of the genera Curtia and Hockinia, monotypic genus, are still controversial. To define anatomical characteristics that help resolve taxonomic problems, the stem and leaf anatomy of seven species of Curtia and Hockinia montana are described. Some characteristics are found in both genera: leaves with uniseriate epidermis, dorsiventral mesophyll, cells of the palisade parenchyma with invaginations, basal acrodromous venation with an incomplete marginal ultimate venation, presence of colleters and nectaries, stem with small wings and internal phloem. The types of stomata, the midrib vascular bundle, and the type and distribution of nectaries were used to separate the genera. The presence/absence of crystals, the sinuosity of the anticlinal walls of the epidermal cells, the type and distribution of stomata, and the distribution of nectaries distinguish species of Curtia. Our results suggest that these anatomical characteristics are potentially useful for clarifying the taxonomy of Gentianaceae, and that they represent an additional tool for distinguishing genera and identifying species of Curtia, particularly pointing out the need to revise the synonymy between C. patula and C. tenuifolia. We also highlight the first report of leaf nectaries and colleters in the Saccifolieae and the first record of stem nectaries in the Gentianaceae.Item Anatomical interpretations of the taxonomy of Chamaecrista (L.) Moench sect. Absus (Leguminosae–Caesalpinioideae)(Plant Systematics and Evolution, 2015-04-19) Coutinho, Ítalo A. C.; Francino, Dayana M. T.; Dalvi, Valdnéa C.; Azevedo, Aristéa A.; Conceição, Adilva de S.; Meira, Renata M. S. A.Chamaecrista (L.) Moench (Caesalpinioideae–Leguminosae) with 330 species is organized into six sections: Apoucouita, Absus, Grimaldia, Chamaecrista, Caliciopsis and Xerocalyx. Section Absus is the largest section of the Chamaecrista and is organized into four subsections, viz., subsect. Adenophyllum, subsect. Baseophyllum, subsect. Otophyllum and subsect. Absus. This section is not monophyletic and has a complex taxonomy. This study aims to anatomically characterize 60 taxa of Chamaecrista, identifying meaningful morphoanatomical characters that may shed light on the evaluations of the taxonomic and phylogenetic framework of Chamaecrista, especially C. sect. Absus. Standard light microscopy techniques were used to anatomically characterize the leaves. The anatomical data were subjected to a multivariate analysis (Jaccard index). Epidermal papillae on the abaxial side, the distribution and types of secretory and tector trichomes, variations in the arrangement of the vascular system of the midvein and the type of arrangement of the vascular system of the petiole are useful for separating species or groups of species. The presence and type of secretory structure, the type and position of stomata and the venation pattern are important in establishing the affinities between sections and subsections. The phenetic analysis demonstrates that the anatomical data contribute to the establishment of affinities between sections and subsections, supporting the elevation of the taxonomic status of the clade Baseophyllum to section and the insertion of C. absus (C. sect. Grimaldia) into C. sect. Absus, corroborating molecular studies.