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Myrcia capixaba and M. forzzae, two new species from the large Neotropical genus Myrcia, are here proposed, described, and illustrated. Both species belong to Myrcia sect. Aguava and are morphologically quite distinct from the other species of the section. Myrcia capixaba occurs in the Atlantic Forest of Espírito Santo and presents a set of features that do not overlap with any other species within M. sect. Aguava: dibrachiate trichomes on the branches, leaves, and inflorescences and externally on the flowers, broadly elliptic to ovate leaves with flat, barely visible secondary venation adaxially, and subterminal panicles. Myrcia forzzae occurs in the Amazon Forest of Mato Grosso and resembles M. gigas, differing in the shorter internodes, vegetative branches and inflorescence rachises densely covered with trichomes (vs. with scattered trichomes or glabrous), and calyx lobes bearing trichomes externally (vs. glabrous). [ABSTRACT FROM AUTHOR]

Two new species of Myrcia sect. Reticulosae, M. carassana and M. revoluta are here described and illustrated. Myrcia carassana was firstly recognized in 1908 by A. F. M. Glaziou but never validly published. This species is similar to M. venosissima but differs by reddish trichomes, inflorescences botryoid or reduced to simple dichasia with longer peduncles, obconic floral buds and calyx lobes internally densely pilose. Myrcia revoluta resembles M. reticulosa but differs by leaves strongly revolute, densely pilose abaxially when mature, and subterminal inflorescences subtended by reduced leaves. [ABSTRACT FROM AUTHOR]

Myrcia longipetiolata, a new species of Myrcia, is here described and illustrated. With a phylogenetic hypothesis, we show that this species belongs to Myrcia clade 10, a morphologically recognized and narrowly distributed group of species, which was recently discovered. Myrcia longipetiolata resembles M. unana due to its long leaves, acute or acuminate leaf apex, cuneate leaf base, long petioles, and they share the same area of occurrence. Myrcia longipetiolata differs from M. unana by its larger leaves, larger number of leaf secondary veins, marginal vein more distant from the leaf margin, lanceolate bracteoles, smaller and truncate, rounded, or apiculate calyx lobes with whitish to yellowish trichomes, and smaller floral disc. Besides the phylogenetic placement of M. longipetiolata within the genus, morphological comparisons with related species and comments on its distribution, habitat, and conservation status are also provided. [ABSTRACT FROM AUTHOR]

• The V. polycephala leaf has a specific type of trichome, unprecedented for the genus. • Some anatomical traits of V. polycephala leaf may be adaptations to xeric environment. • Leaf anatomy can reveal important novelties for taxonomic studies. Varronia polycephala is a medicinal plant used as a substitute of V. curassavica (the popular "erva baleeira") in some traditional communities. This paper aims to describe and illustrate the leaf anatomy of V. polycephala. The results show that V. polycephala presents a distinct type of non-glandular trichome in abundance on the abaxial leaf surface, as well as a single type of glandular trichome on the same surface. Other characteristics observed in V. polycephala include non-glandular trichomes with cystoliths, crystal sand idioblasts, shape of the petiole in cross section, type of vascular bundles and ring collenchyma in the petiole. Histochemical results suggest similarities with V. curassavica , showing the pharmacological potential of V. polycephala. Possible ecological functions of structures and substances are discussed. [ABSTRACT FROM AUTHOR]