Percorrer por autor "Almada, F."
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- A revision of the status of Lepadogaster lepadogaster (Teleostei : Gobiesocidae): sympatric subspecies or a long misunderstood blend of species?Publication . Henriques, M.; Lourenço, R.; Almada, F.; Calado, G.; Gonçalves, D.; Guillemaud, Thomas; Cancela, M. Leonor; Almada, V. C.Molecular (partial mitochondrial 12S ribosomal DNA sequences), morphological and meristic analysis of Lepadogaster lepadogaster lepadogaster, L. l. purpurea and L. zebrina were performed to investigate the relationships between these taxa. On the western shore of mainland Portugal, where the two subspecies of L. lepadogaster occur sympatrically, they differ in microhabitat preferences and their breeding seasons are largely out of phase. This information, combined with data on distribution patterns, led to the following conclusions: Lepadogaster l. purpurea is considered to be a valid species, L. purpurea (Bonnaterre, 1788), different from L. l. lepadogaster, now designated L. lepadogaster (Bonnaterre, 1788). L. zebrina was found to be a synonym of L. lepadogaster. The two newly defined species were found to be in sympatry at Madeira and the Canary islands, the Atlantic coast of the Iberian Peninsula, and the Mediterranean at least as far as Genoa (Italy). Diagnostic characters and a list of synonyms are provided. (C) 2002 The Linnean Society of London, Biological Journal of the Linnean Society, 2002, 76, 327-338.
- Facultative cleaning behaviour of juvenile Diplodus sargus (Sparidae) and its ecological role in marine temperate watersPublication . Neto, J.; Vieira, D.; Abecasis, David; Marques, J.; Gordo, L.; Robalo, J. I.; Bispo, R.; Araújo, M.; Almada, F.The diversity and abundance of cleaner species have been frequently associated with ectoparasite load and ecological wealth of tropical fish communities. Cleaning behaviour in temperate regions has received less attention, with few labrid species being described as cleaners. The context and frequency of cleaning behaviour by juvenile white seabream Diplodus sargus are described. Surface observations from pontoons in yachting marinas were carried out based on a method used in a recent first report of cleaning behaviour by this northeastern Atlantic and Mediterranean sparid. A total of 51 h of observations revealed that these juveniles (<10 cm total length [TL]) display similar or higher cleaning rates (13.1 cleaning events per hour) compared to other temperate cleaners. The high cleaning rates, high abundance of young D. sargus on rocky shores along their distribution area and preferential targeting of adults by coastal fisheries highlight the ecological importance of D. sargus. The most common client species include grey mullets (Mugilidae), which represent 93.5% of total cleaning events registered. Regarding TL, clients were 4.6 to 6.6 times larger than cleaners. Environmental factors such as water temperature (14.0-24.0°C), wave exposure (6.0-17.0 s) and wind speed (2.0-8.0 m s-1) influence white seabream cleaning rates. Thus, a combination of factors may affect the health of temperate client fish communities. On a different perspective, these results also highlight the potential of juvenile D. sargus in integrated multitrophic aquaculture. In conclusion, white seabream cleaning behaviour plays an important role in temperate fish communities and its relevance in different habitats should be further assessed.
- Phylogenetic relationships of the north-eastern Atlantic and Mediterranean blenniidsPublication . Almada, F.; Almada, V. C.; Guillemaud, T.; Wirtz, PeterThe phylogenetic relationships of 27 north-eastern Atlantic and Mediterranean blennioids are analysed based on a total of 1001 bp from a combined fragment of the 12S and 16S mitochondrial rDNA. The most relevant results with implications in current blenniid taxonomy are: (1) Lipophrys pholis and Lipophrys (= Paralipophrys) trigloides are included in a well-supported clade that by the rule of precedence must be named Lipophrys; (2) the sister species of this clade are not the remaining species of the genus Lipophrys but instead a monotypic genus comprising Cory-phoblennius galerita; (3) the smaller species of Lipophrys were recovered in another well-supported and independent clade, which we propose to be recognized as Microlipophrys; (4) although some authors included the genera Salaria and Lipophrys in a single group we have never recovered such a relationship. Instead, Salaria is more closely related to the genera Scartella and Parablennius; (5) the genus Parablennius, which was never recovered as a monophyletic clade, is very diverse and may include several distinct lineages; (6) the relative position of Aidablennius sphynx casts some doubts on the currently recognized relationships between the different blenniid tribes. Meristic, morphological, behavioural and ecological characters support our results and are also discussed. The possible roles of the tropical West African coast and the Mediterranean in the diversification of blenniids are discussed. (c) 2005 The Linnean Society of London.