[Sporogenesis, sporoderm and mature spore ornamentation in Lycopodiaceae].

Studies on reproductive aspects, spore morphology and ultrastructure of Lycopodiaceae are not very common in the scientific literature, and constitute essential information to support taxonomic and systematic relationships among the group. In order to complete existing information, adding new and broader contributions on these topics, a comparative analysis of the sporogenesis ultrastructure, with emphasis on cytological aspects of the sporocyte coat development, tapetum, monoplastidic and polyplastidic meiosis, sporoderm ontogeny and ornamentation of the mature spores, was carried out in 43 taxa of eight genera of the Lycopodiaceae: Austrolycopodium, Diphasium, Diphasiastrum, Huperzia (including Phlegmariurus), Lycopodium, Lycopodiella, Palhinhaea and Pseudolycopodiella growing in the Andes of Colombia and the Neotropics. For this study, the transmission elec- tron microscopy (TEM) samples were collected in Cauca and Valle del Cauca Departments, while most of the spores for scanning electron microscopy (SEM) analysis were obtained from herbarium samples.

[Arborescent species of the genus Blechnum (Blechnaceae: Pteridophyta)].

Although the genus Blechnum has been largely studied, problems of species characterization, nomenclature, classification and taxonomy remain unsolved. For these reasons, in this study we intend to deepen in the characterization of the arborescent group of Blechnum with a review of eight species: B. brasiliense, B.

[Pollen morphology of neotropical species of Podostemum (Malpighiales: Podostemaceae)].

Pollen morphology of neotropical species of Podostemum is described for the first time with light (LM) and scanning electronic microscopes (SEM), using pollen dehydration by critical point. Herbarium specimens under study are P. comatum, P.

[Pollen morphology in species of Canna (Cannaceae), and systematics implications].

The morphology of pollen grains of eight taxa of Canna, C. ascendens, C. coccinea, C compacta, C.

Sporophyte morphology and gametophyte development of the fern Blechnum sprucei (Pteridophyta: Blechnaceae).

The fern Blechnum sprucei grows in Mesoamerica (Costa Rica) and South America, from Colombia to Bolivia, SE and centre of Brazil, Paraguay and Argentina. It is a distinctive, somewhat vulnerable, mostly orophilous species. Fresh and dry herbarium material was used for this study.