Browsing by Author "Fletcher, Robert L."
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- Life history and morphological studies of Punctaria tenuissima (Chordariaceae, Phaeophyceae), a new record for the AzoresPublication . Parente, Manuela I.; Fletcher, Robert L.; Neto, Ana I.; Tittley, Ian; Sousa, Ana F.; Draisma, Stefano; Gabriel, DanielaPunctaria tenuissima (Chordariaceae, Phaeophyceae) is reported for the first time from the Azores. Erect thalli were collected on the Island of Sa˜o Miguel; they were up to 3 cm long, flattened and often twisted. The plurilocular sporangia were formed from surface cells that were quadrate or rectangular in surface view. Unilocular sporangia were not observed in the field. In culture, the plurispores of P. tenuissima developed into Hecatonema-like, tufted, prostrate thalli that formed plurilocular sporangia. The plurispores of the prostrate thalli cultured at 158C with a long day (LD) photoperiod developed into new prostrate thalli, which in turn formed plurilocular sporangia. This cycle was repeated 5 times, resulting in several generations of reproductive prostrate thalli. When these cultures were cooled to 108C with a short day (SD) photoperiod, new erect thalli developed from the prostrate thalli resembling the thalli collected in the field. These erect blades produced unilocular and plurilocular sporangia on the same or on different thalli. The plurispores and unispores produced by the erect thalli at 108C under SD conditions once again developed into new prostrate thalli. This is the first report of unilocular sporangia formed in cultures of P. tenuissima. Sexual reproduction was not observed. The culture conditions, particularly temperature and daylength, appeared to influence the formation of erect blades. The Punctaria-like thalli were produced in 108C/SD conditions, whilst the Hecatonema-like thalli were produced under 108–158C/LD and SD conditions. These results are similar to those reported for P. tenuissima from other locations and suggest the occurrence of both direct and heteromorphic life histories in the Azorean algae.
- Life history and phenology of Colpomenia sinuosa (Mertens ex Roth) Derbès & Solier (Scytosiphonaceae, Phaeophycota) in the Azores.Publication . Toste, Marisa F.; Parente, Manuela I.; Neto, Ana I.; Fletcher, Robert L.
- Life history and phenology of Hydroclathrus clathratus (Scytosiphonaceae, Phaeophyceae) in the Azores.Publication . Toste, Marisa F.; Parente, Manuela I.; Neto, Ana I.; Fletcher, Robert L.Hidroclathrus clathradus is a common specie on the rocky intertidal shores of the island of São Miguel, Azores, mainly in spring and summer. Fertile saccate thaili appear in spring and disappear from late summer onward. Two types of life history were observed in culture: a direct-type and a heteromorphic, monophasic life history. In the direct type, reproductive cells from erect plants collected in the field developed directly into new erect thaili with plurilocular sporangia. In the heteromorphic life-hystory pattern, plurispores from the plurilocular sporangia of the erect thaili developed into filamentous prostate microthalli. These developed unilocular and plurilocular sporangia in both short-day and long-day conditions at 15-22 ºC. Unispores released from the unlocular sporangia developed into saccate thaili, whereas plurispores gave rise to filamentous prostate microthaili.
- Life history and phenology of Hydroclathrus clathratus (Scytosiphonaceae, Phaeophycota) in the Azores.Publication . Toste, Marisa F.; Parente, Manuela I.; Neto, Ana I.; Fletcher, Robert L.
- Life history of Colpomenia sinuosa (Scytosiphonaceae, Phaeophyceae) in the Azores.Publication . Toste, Marisa F.; Parente, Manuela I.; Neto, Ana I.; Fletcher, Robert L.Colpomenia sinuosa (Mertens ex Roth) Derbès and Solier (Scytosiphonaceae, Phaeophyceae) is a common species on the rocky intertidal shores of the Azores, where reproductive gametophytes occur throughout the year. Life-history studies of this species were carried out in culture, and both sexual and asexual reproduction were observed. Anisogamous gametes fused to form zygotes. The zygotes gave rise to a filamentous prostrate sporophyte generation bearing unilocular sporangia, under both short-day and long-day conditions at 15 and 22° C, and to both unilocular and plurilocular sporangia, under the lower temperature condition. Unispores developed into gametophytes, and plurispores gave rise to filamentous sporophytes. Asexual reproduction was carried out by unfused female gametes and asexual plurispores produced from the same gametophyte. Unfused gametes developed into filamentous prostrate sporophytes producing unilocular sporangia in both culture conditions, and unispores released from the sporangia gave rise to gametophytes. Asexual plurispores from field gametophytes, under both culture conditions, developed directly into new gametophytes. The species exhibited three types of life history: a heteromorphic, diplohaplontic; a heteromorphic, monophasic (both with alternation between the erect and filamentous prostrate thalli); and a monomorphic, monophasic.
- Life history studies and ecological observations of Endarachne binghamiae J. Agardh (Scytosiphonaceae, Phaeophycota) from the Azores.Publication . Parente, Manuela I.; Neto, Ana I.; Fletcher, Robert L.
- Life history studies and ecological observations of Endarachne binghamiae J. Agardh (Scytosiphonaceae, Phaeophycota) from the Azores.Publication . Parente, Manuela I.; Neto, Ana I.; Fletcher, Robert L.
- Marine algal flora of Flores and Corvo Islands, AzoresPublication . Neto, Ana I.; Parente, Manuela I.; Tittley, Ian; Fletcher, Robert L.; Farnham, William F.; Costa, Ana C.; Botelho, Andrea Z.; Monteiro, Sandra; Resendes, Roberto; Afonso, Pedro; Prestes, Afonso L.; Álvaro, Nuno V.; Milla-Figueras, David; Neto, Raul M. A.; Azevedo, José M. N.; Moreu, IgnacioBACKGROUND The algal flora of the western group of the Azores archipelago (Islands of Flores and Corvo) has attracted the interest of many researchers on numerous past occasions (such as Drouet 1866, Trelease 1897, Gain 1914, Schmidt 1929, Schmidt 1931, Azevedo et al. 1990, Fralick and Hehre 1990, Neto and Azevedo 1990, Neto and Baldwin 1990, Neto 1996, Neto 1997, Neto 1999, Tittley and Neto 1996, Tittley and Neto 2000, Tittley and Neto 2005, Tittley and Neto 2006, Azevedo 1998, Azevedo 1999, Tittley et al. 1998, Dionísio et al. 2008, Neto et al. 2008). Despite this interest, the macroalgal flora of the Islands cannot be described as well-known with the published information reflecting limited collections preformed in short-term visits by scientists. To overcome this, a thorough investigation, encompassing collections and presence data recording, has been undertaken for both the littoral and sublittoral regions, down to a depth of approximately 40 m, covering a relatively large area on both Islands (approximately 143 km² for Flores and 17 km² for Corvo). This paper lists the resultant taxonomic records and provides information on species ecology and occurrence around both these Islands, thereby improving the knowledge of the Azorean macroalgal flora at both local and regional scales. NEW INFORMATION For the Island of Flores, a total of 1687 specimens (including some taxa identified only to genus level) belonging to 196 taxa of macroalgae are registered, comprising 120 Rhodophyta, 35 Chlorophyta and 41 Ochrophyta (Phaeophyceae). Of these taxa, 128 were identified to species level (80 Rhodophyta, 22 Chlorophyta and 26 Ochrophyta), encompassing 37 new records for the Island (20 Rhodophyta, 6 Chlorophyta and 11 Ochrophyta); two Macaronesian endemics (Laurencia viridis Gil-Rodríguez & Haroun and Millerella tinerfensis (Seoane-Camba) S.M.Boo & J.M.Rico); six introduced (the Rhodophyta Asparagopsis armata Harvey, Neoizziella divaricata (C.K.Tseng) S.-M.Lin, S.-Y.Yang & Huisman and Symphyocladia marchantioides (Harvey) Falkenberg; the Chlorophyta Codium fragile subsp. fragile (Suringar) Hariot; and the Ochrophyta Hydroclathrus tilesii (Endlicher) Santiañez & M.J.Wynne and Papenfussiella kuromo (Yendo) Inagaki); and 14 species of uncertain status (10 Rhodophyta, two Chlorophyta and two Ochrophyta). For the Island of Corvo, a total of 390 specimens distributed in 56 taxa of macroalgae are registered, comprising 30 Rhodophyta, nine Chlorophyta and 17 Ochrophyta (Phaeophyceae). Whilst a number of taxa were identified only to the genus level, 43 were identified to species level (22 Rhodophyta, eight Chlorophyta and 13 Ochrophyta), comprising 22 new records for the Island (nine Rhodophyta, four Chlorophyta and nine Ochrophyta), two introduced species (the Rhodophyta Asparagopsis armata and the Chlorophyta Codium fragile subsp. fragile and seven species of uncertain status (five Rhodophyta and two Ochrophyta).
- Marine algal flora of São Miguel Island, AzoresPublication . Neto, Ana I.; Moreu, Ignacio; Rosas-Alquicira, Edgar; León-Cisneros, Karla; Cacabelos, Eva; Botelho, Andrea Z.; Micael, Joana; Costa, Ana C.; Neto, Raul M. A.; Azevedo, José M. N.; Monteiro, Sandra; Resendes, Roberto; Afonso, Pedro; Prestes, Afonso L.; Patarra, Rita F.; Álvaro, Nuno V.; Milla-Figueras, David; Ballesteros, Enric; Fletcher, Robert L.; Farnham, William F.; Tittley, Ian; Parente, Manuela I.BACKGROUND The macroalgal flora of the Island of São Miguel (eastern group of the Azores Archipelago) has attracted the interest of many researchers in the past, the first publications going back to the nineteenth century. Initial studies were mainly taxonomic, resulting in the publication of a checklist of the Azorean benthic marine algae. Later, the establishment of the University of the Azores on the Island permitted the logistic conditions to develop both temporal studies and long-term research and this resulted in a significant increase on research directed at the benthic marine algae and littoral communities of the Island and consequent publications. Prior to the present paper, the known macroalgal flora of São Miguel Island comprised around 260 species. Despite this richness, a significant amount of the research was never made public, notably Masters and PhD theses encompassing information regarding presence data recorded at littoral and sublittoral levels down to a depth of approximately 40 m around the Island and the many collections made, which resulted in vouchers deposited in the AZB Herbarium Ruy Telles Palhinha and the LSM- Molecular Systematics Laboratory at the Faculty of Sciences and Technology of the University of the Azores. The present publication lists the macroalgal taxonomic records, together with information on their ecology and occurrence around São Miguel Island, improving the knowledge of the Azorean macroalgal flora at local and regional scales. NEW INFORMATION A total of 12,781 specimens (including some identified only to genus) belonging to 431 taxa of macroalgae are registered, comprising 284 Rhodophyta, 59 Chlorophyta and 88 Ochrophyta (Phaeophyceae). Of these, 323 were identified to species level (212 Rhodophyta, 48 Chlorophyta and 63 Ochrophyta), of which 61 are new records for the Island (42 Rhodophyta, 9 Chlorophyta and 10 Ochrophyta), one an Azorean endemic (Predaea feldmannii subsp. azorica Gabriel), five are Macaronesian endemisms (the red algae Botryocladia macaronesica Afonso-Carrillo, Sobrino, Tittley & Neto, Laurencia viridis Gil-Rodríguez & Haroun, Millerella tinerfensis (Seoane-Camba) S.M.Boo & J.M.Rico, Phyllophora gelidioides P.Crouan & H.Crouan ex Karsakoff and the green alga Codium elisabethiae O.C.Schmidt), 19 are introduced species (15 Rhodophyta, two Chlorophyta and two Ochrophyta) and 32 are of uncertain status (21 Rhodophyta, five Chlorophyta and six Ochrophyta).
- Morphological studies of Hapalospongidion macrocarpum and Nemoderma tingitanum (phaeophyceae) from the Salvage Islands (Madeira archipelago).Publication . Parente, Manuela I.; Neto, Ana I.; Fletcher, Robert L.; Gil-Rodríguez, María C.; Haroun, Ricardo J.Two species of encrusting brown algae (Phaeophyceae) are newly recorded for the Salvage Islands (Madeira Archipelago) viz. Nemoderma tingitanum and Hapalospongidion macrocarpum. The species are described, and information is presented concerning their ecology, morphology and geographical distribution in the Atlantic.