Browsing by Author "Riosmena-Rodriguez, Rafael"
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- Are the reported coralline red seaweeds species for the Macaronesian region taxonomically still valid?Publication . Rosas-Alquicira, Edgar; Riosmena-Rodriguez, Rafael; Neto, Ana I.
- Diagnosing characters in Amphiroa (Corallinales) and the genus diversity evaluation in the Azores.Publication . Rosas-Alquicira, Edgar; Riosmena-Rodriguez, Rafael; Neto, Ana I.
- Life-cycle of Scinaia interrupta (Nemaliales, Rhodophyta)Publication . León-Cisneros, Karla; Nogueira, Eunice M.; Riosmena-Rodriguez, Rafael; Neto, Ana I.The life-cycle of Scinaia interrupta (A.P. de Candolle) M. J. Wynne was investigated in vitro using four irradiance regimes: 4, 8, 12 and 16 μmol photons mˉ² sˉ¹. A triphasic heteromorphic life-cycle was observed. Carpospores released by cystocarps of gametophytes collected in the field developed into filamentous tetrasporophytes, which produced tetrahedral tetrasporangia. Tetrasporangial development was accelerated under higher irradiance levels. Tetraspores germinated into filamentous protonemal gametophytes, initially identical to the tetrasporophyte. Filamentous gametophytes developed apical utricles and gave rise directly to the fleshy gametophyte. Further development of the fleshy gametophyte was not observed at the lowest irradiance regime (4 μmol photons mˉ² sˉ¹). The present study reports for the first time the influence of the irradiance regime on the initial tetrasporangial development and in the development of the fleshy gametophyte, and reinforces the importance of light intensity on Scinaia life-cycle. Production of apical utricles by the filamentous gametophyte is newly reported for the genus.
- Life-cycle of Scinaia interrupta (Nemaliales; Rhodophyta)Publication . León-Cisneros, Karla; Nogueira, Eunice M.; Riosmena-Rodriguez, Rafael; Neto, Ana I.
- Molecular characterization of the red algal genus Scinaia (Scinaiaceae, Nemaliales) from the Azorean Archipelago with morphological observations on S. interrupta.Publication . León-Cisneros, Karla; Gabriel, Daniela; Neto, Ana I.; Fredericq, Suzanne; Riosmena-Rodriguez, Rafael
- Morphological and anatomical observations on the genus Scinaia (Nemaliales; Rhodophyta) from the Gulf of California, Mexico.Publication . León-Cisneros, Karla; Riosmena-Rodriguez, Rafael; Neto, Ana I.
- New additions to the Azorean algal flora with ecological observations on rhodolith formations.Publication . Rosas-Alquicira, Edgar; Riosmena-Rodriguez, Rafael; Neto, Ana I.; Couto, Ruben P.
- New additions to the Azorean algal flora, with ecological observations on rhodolith formationsPublication . Rosas-Alquicira, Edgar; Riosmena-Rodriguez, Rafael; Couto, Ruben P.; Neto, Ana I.Non-geniculate coralline algae are abundant and ecologically important in the Azorean littoral, although they have been investigated only sporadically. This paper is the first report on the occurrence of Neogoniolithon brassica-florida, Lithophyllum crouanii and Phymatolithon calcareum as rhodoliths in the Azores (the first two in Ilhéu de Vila Franca, São Miguel Island, and the third at Lajes do Pico, Pico Island). At each sampling site area and percent cover of rhodoliths were estimated along their depth distribution range, and for each species rhodolith density, branch density, and sphericity were determined. Rhodoliths were distributed between 2 and 4 m depth, and differences were found in the percent cover between sites, and in rhodolith density, maximum length, branch density and sphericity between species, with higher values for Neogoniolithon brassica-florida. Sphericity differences may result from differences in growth characteristics between species.
- Ontogeny of conceptacles in Amphiroa (Corallinales, Rhodophyta)Publication . Rosas-Alquicira, Edgar; Hernández-Carmona, Gustavo; Riosmena-Rodriguez, Rafael; Neto, Ana I.
- A re-evaluation of Scinaia (Nemaliales, Rhodophyta) in the Azores.Publication . Léon-Cisneros, Karla; Riosmena-Rodriguez, Rafael; Neto, Ana I.The genus Scinaia in the Azores is re-evaluated based on historical and recent collections. A combination of morphological and anatomical diagnostic characters was used for species segregation, and a key for Azorean species determination is presented. Anatomical information associated to the hair development is described for the first time for the genus. The occurrence of S. furcellata and S. interrupta is confirmed for the archipelago. The presence of S. acuta is reported for the first time in the Azores, representing a spread from Australia to the N-Atlantic and specifically into the Macaronesian region. Its occurrence in the archipelago and the Canaries is discussed as a possible introduction.