Abstract:RESUMO -(Morfoanatomia das brácteas em ). All species are found in São Paulo State. In the subg. Heliconia the bracts are cymbiform and in Stenochlamys they are lanceolate-conduplicated. All species have bracts with uniseriate epidermis, with thin-walled cells, tetracytical stomata in H. hirsuta and H. subulata, and polycytical in the others; the vascular bundles and air canals are distributed in arc-shaped and the fiber bundles are situated close to the abaxial surface. The bract shape, associated with the di… Show more
“…These air lacunae are formed by large, thinwalled, translucent cells. This character is similar to previous reports on Cyperaceae and Heliconiaceae (Govindarajalu 1968;Simão and Scatena 2004). This resemblance, together with the assumption of tissue continuity from the leaf sheath, pseudopetiole and leaf blade, strengthen our assumption that the translucent cells in the mesophyll of Mapania are indeed aerenchyma instead of aquiferous parenchyma, as erroneously indicated by Alves et al (2002) for M. pycnocephala, M. sylvatica and species of Hypolytrum.…”
Section: Discussionsupporting
confidence: 90%
“…The basal leaf sheath in M. macrophylla presents more vascular and more fiber bundles, both on various levels. A similar pattern was found in involucral bracts of Heliconia (Heliconiaceae, Simão & Scatena 2004). This feature occurs specially on basal leaves of M. macrophylla, in which they are long and robust (up to 1.2 m, based on Simpson 1992) and thus require a more complex supportive tissue.…”
Mapania belongs to Mapanioideae, a quite controversial subfamily in Cyperaceae due to the existence of unusual characters in both reproductive and vegetative organs. The genus is represented by seven species in Northern Brazil but taxonomic valuable information related to the leaf organs is still unknown. The present study aimed the anatomical description of the leaf organs (either basal leaves or cataphylls and involucral bracts) of three representative Brazilian species of Mapania. Samples of cataphylls, basal leaves and involucral bracts were sectioned and stained for observations under light microscopy. The involucral bracts provide the most elucidative characters (ten) to distinguish the three species The basal leaves provides six distinguishing characters and are useful to M. macrophylla and M. pycnostachya, as they are absent in M. sylvatica. Mesophyll arrangement in the involucral bracts supports the circumscription of M. macrophylla and M. pycnostachya in M. sect. Pycnocephala and of M. sylvatica in M. sect. Mapania. Some features as thin-walled epidermal cells, stomata level and aerenchyma were considered to be adaptive to the humid environment in which the species occur. The translucent cells are here considered as aerenchyma precursors and a supportive function is assumed for the bulliform cells on the basal leaves and involucral bracts. No silica bodies were found which confirm it as a diagnostic character of Mapania among Hypolytreae genera. KEYWORDS: aerenchyma, cataphylls, Hypolytreae, involucral bracts, Poales Importância dos caracteres anatômicos foliares na caracterização de três espécies de Mapania (Mapanioideae, Cyperaceae) da Floresta Amazônica, Brasil RESUMO Mapania pertence à subfamília Mapanioideae que apresenta caracteres incomuns às demais Cyperaceae, tanto vegetativos como reprodutivos. O gênero é representado por sete espécies no norte do Brasil e apresenta ainda lacunas de informações especialmente relacionadas aos órgãos foliares. O presente estudo objetivou a descrição anatômica dos órgãos foliares (folhas basais, ou catafilos, e brácteas involucrais) de três espécies representativas de Mapania no território brasileiro. Amostras de catafilos, folhas basais e brácteas involucrais foram seccionadas e coradas para observações em microscopia de luz. As brácteas involucrais foram as mais elucidativas na separação das espécies, com dez caracteres variáveis, uma vez que ocorrem em todas as espécies durante o estágio reprodutivo. As folhas basais forneceram seis caracteres úteis na distinção de M. macrophylla e M. pycnostachya, já que não ocorrem em M. sylvatica. seguidas das folhas basais. O arranjo do mesofilo das brácteas involucrais suporta a circunscrição de M. macrophylla e M. pycnostachya em M. sect. Pycnocephala e de M. sylvatica em M. sect. Mapania. Características adaptativas ao ambiente úmido também foram encontradas, como epiderme com paredes delgadas, níveis dos estômatos e presença de aerênquima. As células translúcidas do mesofilo foram descritas como precursoras de...
“…These air lacunae are formed by large, thinwalled, translucent cells. This character is similar to previous reports on Cyperaceae and Heliconiaceae (Govindarajalu 1968;Simão and Scatena 2004). This resemblance, together with the assumption of tissue continuity from the leaf sheath, pseudopetiole and leaf blade, strengthen our assumption that the translucent cells in the mesophyll of Mapania are indeed aerenchyma instead of aquiferous parenchyma, as erroneously indicated by Alves et al (2002) for M. pycnocephala, M. sylvatica and species of Hypolytrum.…”
Section: Discussionsupporting
confidence: 90%
“…The basal leaf sheath in M. macrophylla presents more vascular and more fiber bundles, both on various levels. A similar pattern was found in involucral bracts of Heliconia (Heliconiaceae, Simão & Scatena 2004). This feature occurs specially on basal leaves of M. macrophylla, in which they are long and robust (up to 1.2 m, based on Simpson 1992) and thus require a more complex supportive tissue.…”
Mapania belongs to Mapanioideae, a quite controversial subfamily in Cyperaceae due to the existence of unusual characters in both reproductive and vegetative organs. The genus is represented by seven species in Northern Brazil but taxonomic valuable information related to the leaf organs is still unknown. The present study aimed the anatomical description of the leaf organs (either basal leaves or cataphylls and involucral bracts) of three representative Brazilian species of Mapania. Samples of cataphylls, basal leaves and involucral bracts were sectioned and stained for observations under light microscopy. The involucral bracts provide the most elucidative characters (ten) to distinguish the three species The basal leaves provides six distinguishing characters and are useful to M. macrophylla and M. pycnostachya, as they are absent in M. sylvatica. Mesophyll arrangement in the involucral bracts supports the circumscription of M. macrophylla and M. pycnostachya in M. sect. Pycnocephala and of M. sylvatica in M. sect. Mapania. Some features as thin-walled epidermal cells, stomata level and aerenchyma were considered to be adaptive to the humid environment in which the species occur. The translucent cells are here considered as aerenchyma precursors and a supportive function is assumed for the bulliform cells on the basal leaves and involucral bracts. No silica bodies were found which confirm it as a diagnostic character of Mapania among Hypolytreae genera. KEYWORDS: aerenchyma, cataphylls, Hypolytreae, involucral bracts, Poales Importância dos caracteres anatômicos foliares na caracterização de três espécies de Mapania (Mapanioideae, Cyperaceae) da Floresta Amazônica, Brasil RESUMO Mapania pertence à subfamília Mapanioideae que apresenta caracteres incomuns às demais Cyperaceae, tanto vegetativos como reprodutivos. O gênero é representado por sete espécies no norte do Brasil e apresenta ainda lacunas de informações especialmente relacionadas aos órgãos foliares. O presente estudo objetivou a descrição anatômica dos órgãos foliares (folhas basais, ou catafilos, e brácteas involucrais) de três espécies representativas de Mapania no território brasileiro. Amostras de catafilos, folhas basais e brácteas involucrais foram seccionadas e coradas para observações em microscopia de luz. As brácteas involucrais foram as mais elucidativas na separação das espécies, com dez caracteres variáveis, uma vez que ocorrem em todas as espécies durante o estágio reprodutivo. As folhas basais forneceram seis caracteres úteis na distinção de M. macrophylla e M. pycnostachya, já que não ocorrem em M. sylvatica. seguidas das folhas basais. O arranjo do mesofilo das brácteas involucrais suporta a circunscrição de M. macrophylla e M. pycnostachya em M. sect. Pycnocephala e de M. sylvatica em M. sect. Mapania. Características adaptativas ao ambiente úmido também foram encontradas, como epiderme com paredes delgadas, níveis dos estômatos e presença de aerênquima. As células translúcidas do mesofilo foram descritas como precursoras de...
“…This can be observed also in other groups of monocotyledons, such as Heliconia (Heliconiaceae), where characteristics such as the arrangement of fibre bundles in the abaxial region of the leaf, the size of the air canals in the mesophyll, and the form of the bracts provide important characteristics in determining the variation that exists among the subgenera (Sima˜o and Scatena, 2004).…”
“…In Brazil, H. spathocircinata (Heliconiaceae) is found in lowland Atlantic rainforest ( Berry and Kress 1991 ; Braga 2020 ) and blossoms in the wet season, between December and February ( Cruz et al 2006 ). This plant bears long-lasting inflorescences with cimbiform, brightly colored bracts varying from yellow to red, which are associated with ornithophily ( Berry and Kress 1991 ; Andersson 1998 ; Simão and Scatena 2004 ). Its plain and yellow flowers are inserted in the bracts, and visitors can only access the corolla legitimately through its opening at the apex of the flower.…”
Many plants pollinated by nectar-foraging animals have to maintain a balance between legitimate visitor attraction strategies and mechanisms that minimize illegitimate visits. This study investigated how floral display and neighboring species composition influences nectar robbing in the tropical ornithophilous herb Heliconia spathocircinata. We tested the role of inflorescence display, flower abundance, and neighboring species in the reduction of nectar robbing in H. spathocircinata. Our results indicate that nectar robbing hummingbird activity was higher in moderately large inflorescence displays and that the frequency of nectar robbing in H. spathocircinata decreases with increased flower abundance and the presence of neighboring plant species. Neighboring non-ornithophilous plants decreased the frequency of nectar robbing in H. spathocircinata flowers to a greater extent than ornithophilous ones. These results suggest that nectar robbing hummingbirds are attracted to similar conditions that attract legitimate visitors, and that spatial aggregation and mixed-species displays may represent a mechanism to dilute nectar robbing effects at an individual level.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.