Lankesteriana

Osmophore diversity in the catasetum cristatum alliance (orchidaceae: catasetinae)

AbstractCatasetum is a neotropical orchid genus of 130 species characterized by its unisexual flowers. They are pollinated by male Euglossini bees. It is widely know that these bees collect volatile compounds in Catasetum from structures called osmophores. However, there is little information on morpho-anatomy and histochemistry of secretory tissues for this neotropical genus and data are lacking. Based on these arguments members of the Catasetum cristatum alliance, namely C. arietinum, C. ariquemense, C. barbatum, C. carolinianum, C. cristatum, C. lanciferum, C. multifidum, C. multifissum, C. rivularium and C. semicirculatum were analyzed. The labellum of male flowers of this alliance is elongate and with fimbriate margins, possessing two protuberances and a median saccate portion. The labellum of female flowers is galeiform and there is no ornamentation. The entire adaxial surface of the labellum is secretory in both sexes, including the fimbriae of male flowers. The structure of the secretory tissue is similar among species, and they are composed of a simple epidermis and five layers of underlying parenchyma. In most species the epidermis is flat, and cells are elongated in the saccate portion. In C. ariquemense and C. carolinianum the epidermal cells are papillous, while in C. semicirculatum they have convex surface (male flowers). The histochemical analysis detected lipophilic droplets and starch grains inside the secretory cells. All characteristics observed are encountered in secretory tissues with high-energy demand, as is common in osmophores.

A new species of catasetum (orchidaceae, epidendroideae, cymbidieae) from the southern brazilian amazon

AbstractCatasetum colidense, from margins of the Teles Pires River, Mato Grosso State, Brazil, is described and illustrated. The new species is compared with morphologically similar species.

ResumoÉ descrita e ilustrada Catasetum colidense, oriunda das margens do rio Teles Pires, estado de Mato Grosso, Brasil. A nova espécie é comparada com as espécies morfologicamente próximas.

The genus vanda (orchidaceae: aeridinae) in the philippines: two new species and a key to the species in the archipelago

AbstractTwo Philippine Vanda species long confused with the Javanese species V. limbata and V. helvola are here described as V. mariae and V. cootesii. A key to the genus Vanda in the Philippines is provided.

A new oliveriana (orchidaceae: oncidiinae) from Ecuador

AbstractA new species of Oliveriana is described and illustrated. It is compared with and distinguished from all other listed members of the genus by a unique combination of distinct features, such as the extremely elongate and narrow leaves, and a flower with a fleshy triangular lip. It is speculated here that this new species may be self-pollinating due to the high success of seed pod production, which is unusual among genera in Oncidiinae.

Three new species of pleurothallis (orchidaceae: pleurothallidinae) in subsection macrophyllaefasciculatae from northern south america

AbstractThe history of the taxonomy of Pleurothallis R.Br. subsection Macrophyllae-Fasciculatae and recent descriptions in that group are summarized. The phylogenetic position of the group based on preliminary molecular data and the appropriateness of the proposed genera Acronia C.Presl. and Zosterophyllanthos Szlach. & Marg. for this group are discussed. Three new species from northern South America are described: Pleurothallisrubrifolia from southeastern Ecuador and northeastern Peru; Pleurothallis nangaritzae from southeastern Ecuador; and Pleurothallis castanea. Labellar micromorphology examined by scanning electron microscopy for P. rubrifolia and P. nangaritzae is discussed in relation to taxonomy and possible pollinator interactions.

A new masdevallia (orchidaceae: pleurothallidinae) from a deforested area in the huanuco region of Peru

AbstractA new and showy species of Masdevallia from the Huanuco region in Peru is described and illustrated with a line drawing and color photographs. It belongs to the subgenus Masdevallia, section Masdevallia. The new species is compared to several more or less morphologically similar species, such as M. burianii, M. cranion and M. popowiana that appear to be closely related. The new species differs from them by a combination of features, including the rather fleshy leaves and the bell-shaped flowers covered internally with magenta to white pubescence.