Lankesteriana

**Nectary structure and nectar in Sobralia and Elleanthus (sobralieae: orchidaceae)**

With approximately 200 species, the tribe Sobralieae is a dominant and common Neotropical group of orchids, yet little is known of variation in floral morphology as it relates to their pollination. As currently circumscribed, the tribe includes four genera that differ considerably in flower size and morphology: Elleanthus, Epilyna, Sertifera, and Sobralia. Although nectar-foraging pollinators are known for some species, the relationships of pollination to deceit and to nectar production are all poorly understood. We examined pollination-related of nectaries and nectar characteristics (presence/absence, volume, and concentration) for major clades of Sobralieae. Some species produce abundant nectar, but many species offer no reward. When present, nectar is secreted by thickened calli at the lip base. The cells of the nectariferous calli contain starch, which is rapidly converted to sugar during a brief anthesis (often lasting only one day). Most Sobralia flowers are relatively large, bee-pollinated, with a gullet-shaped lip, false nectary, large pollinia, and offer no reward. Elleanthus flowers are relatively small with a legitimate nectar reward, and most species are hummingbirdpollinated. Hummingbird-pollinated Sobralieae flowers are relatively small, brightly colored in the perianth and/or the subtending bracts, somewhat tubular, with a lip that forms a cup around the callus for storing nectar, and pollinia that are dark and relatively small.

**Pollination ecology of Rodriguezia granadensis (orchidaceae)**

In this paper we describe the phenotypic variation and pollination ecology of the twig orchid epiphyte Rodriguezia granadensis. The species presents flower color polymorphism (pink to white), suggesting that different color forms might be pollinated by different pollinators. To evaluate this hypothesis, one hundred plants were monitored in the field and their flowering phenology and color polymorphism was noted, two peaks of flowering were noted over the year. We evaluated the reproductive success (pollinaria removal and fruit set) and the visit of potential pollinators to both morphs. Fruit production by autogamy, geitonogamy, xenogamy, and emasculation were compared. Sugar concentration in the nectar was measured with a refractometer. Potential pollinators, euglossini bees, were attracted using methyl salicylate and eugenol. We evidenced that R. granadensis is pollinated by nectar-foraging euglossine bees. The fluctuation in nectar production and the scarce reproductive success among individuals suggests that the orchids may employ an attraction-deceit system as a self-mimetic or a diffuse rewarding phenomenon.

En éste artículo describimos la variación fenotípica y ecología de la polinización de la epífita de ramita Rodriguezia granadensis. La especie presenta polimorfismo para el color de las flores (blanco a rosa), lo que lo llevó a hipotetizar que las diferentes formas de color pueden ser polinizadas por diferentes polinizadores. Para evaluar esta hipótesis, se monitorearon cien plantas en campo y se anotó su fenología de floración y polimorfismo en color. Dos picos de floración se presentan en el año. Evaluamos el éxito reproductivo (fitness masculino y femenino) y la visita de los polinizadores potenciales en ambos morfos. Se puso a prueba la producción de frutos por autogamia, geitonogamia, xenogamia y emasculación. La producción de néctar se midió con un refractómetro. Adicionalmente, usamos trampas de fragancia con salicilato de metilo y eugenol para atraer polinizadores potenciales (abejas euglosinas). Presentamos evidencia de la polinización de R. granadensis por abejas euglosinas que buscan néctar. La fluctuación en la producción de néctar y el escaso éxito reproductivo entre los individuos sugiere que la orquídea puede emplear un sistema de atracción/engaño como auto-mimetismo o un fenómeno de recompensas difusas.

**Three new species of Masdevallia (orchidaceae: pleurothallidinae) from the ayacucho and puno regions in Peru**

Three new species of Masdevallia, subgenus Masdevallia are described, illustrated with line drawings and color photographs, one dwarf species in section Coriaceae and two attractive and rather large species in section Masdevallia. The former section is also treated as the genus Byrsella by Luer (2006). All three new species are distinguished by unique combinations of features that separate them from all other species in the large genus Masdevallia.

**Protocorm-like bodies and plant regeneration from foliar explants of Coelogyne flaccida, a horticulturally and medicinally important endangered orchid of eastern himalaya**

An efficient induction of protocrom-like bodies (PLBs) and plantlet regeneration from the young leaves of in vitro grown seedlings of Coelogyne flaccida, an horticulturally and medicinally important endangered epiphytic orchid, was accomplished in order to develop mass-scale propagation. The young leaves (1.5 cm in length) from 110 days old aseptically germinated seedling were grown in vitro in Murashige and Skoogs (MS) medium supplemented with different concentrations and combinations of NAA ( 0.5-2 mg/L), BAP (0.5-2 mg/L) and Kn ( 0.5-2 mg/L ). The explants produced protocorm-like bodies directly from the epidermal cells of leaf without the formation of intervening callus tissue within four weeks of culture. The highest number of plantlets regenerated through PLBs per explant after 15 weeks was 35-36 in presence of NAA (2mg/l) and Kn (2mg/l). Within 20-25 weeks individual plantlets produced 2-3 leaves and 2-3 roots. Chromosome number from all plants regenerated from leaf explants showed the same chromosome number as the mother plant as 2n = 40. During acclimatization, 80% of the plantlets survived after one month of transplantation.

**Root anatomy of Galeandra leptoceras (orchidaceae)**

Due to the scarce information about the root organization of Galeandra genus representatives, this study aimed to describe the root anatomy of Galeandra leptoceras, describing adaptations related to hydric relations and characters of taxonomic interest. Five roots of three plants were fixed and preserved in 50% alcohol. These ones were cut in midline with the use of razors. The sections were stained with 0.05% Safrablau and mounted in glycerin. It was observed that the roots of species are structurally adapted to epiphytism; however, some anatomical features show that this species requires more frequent watering or environments with constant humidity. The anatomical characteristics described for roots support results reported by authors that include the genus in subtribe Catasetinae, Cymbidieae tribe. The anatomical characters have generic uniformity, serving as a tool for the genuss systematic.