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- A review of the parasites of deep-water fishes from Macaronesian Islands, North-East Atlantic OceanPublication . Costa, Graça; Costa, Luísa; Santos, Maria João; Moreira, E. MeloThe deep-water fish fauna of Macaronesian islands is currently estimated at a total of 1029 different fish species, but records of both ecto- and endoparasites are from only about 30 of those species. This fact presents an exciting field of research for scientists interested in fish parasitology, by exploring the structure of parasite communities and their connections with ecological and oceanographic variables. Research on the effect of climatic changes on the parasite faunas, on the occurrence of fish parasites in man and its impact on human health, has not been carried out to date. The present review aims to collate our present knowledge about the parasites of deep-water fishes of Macaronesia, and to suggest directions for future research on the parasites of fishes from the deepwater realm. A checklist of the parasites infecting the deep-water fishes from this region is included.
- Suspected viral erythrocytic necrosis (VEN) in the intertidal fish Mauligobius maderensis from Madeira, PortugalPublication . Eiras, J. C.; Costa, G.; Biscoito, M.; Davies, A. J.Suspected viral erythrocytic necrosis (VEN) was detected in two specimens of the intertidal fish Mauligobius maderensis (Teleostei: Gobiidae) from Madeira, Portugal. While one host was lightly infected, the other showed intraerythrocytic cytoplasmic inclusions within all mature erythrocytes examined. The inclusions were round to oval, 0-8-2-0 |im in diameter, and most were associated with dense eosinophilic granular areas of various sizes and shapes. Up to three of these granular regions accompanied each inclusion body, but they were sometimes widely separated from it. In a number of infected erythrocytes, a granular halo was observed surrounding the nucleus. The cytoplasm enclosed by the halo often had a different refringence from that outside. None of the 120 other fishes examined from Madeira, representing 43 species of intertidal, pelagic, and deep-sea origin, had detectable infections.
- A checklist of digenean parasites (Platyhelminthes: Digenea) infecting molluscs and fishes in Portuguese waters (Northeast Atlantic)Publication . Costa, G.; Soares, S.; Moreira, E. MeloThe present work is a compilation of the digenean parasites infecting molluscs (gastropods and bivalves), crabs and fishes of the Atlantic coast of Portugal and the Archipelagos of Azores and Madeira, based on literature sources, including research conducted by the present authors. A total of 65 digenea taxa were found, belonging to 24 families, infecting gastropods, bivalves, shore crabs and fishes. The most representative families of digeneans were the Hemiuridae (11 taxa), followed by the Bucephalidae (5 taxa), Opecoelidae (5 taxa) and the Zoogonidae (5 taxa). Hosts, site of infection, sampling locality and life cycle strategy are given when available. Further fields of research on the digenean parasites are suggested.
- Soil conditions and evolution of aluminium resistance among cultivated and wild plant species on the Island of MadeiraPublication . Ganança, J. F. T.; Abreu, I.; Sousa, N. F.; Paz, R. F.; Caldeira, P.; Santos, T. M. M. dos; Costa, G.; Slaski, J. J.; Carvalho, M. Â. A. Pinheiro deSoil samples collected from different soil formations throughout the Island of Madeira were analysed for pH, aluminium (Al) and organic matter content. On average, the Madeira soils appeared to be acid with a mean pH of 5.01, containing 0.79 cmol/kg of ionic Al and 3.02% organic matter, which may create favourable conditions for the development of Al resistance among plant species inhabiting the island. Six plant species were evaluated for their resistance to Al using the erichrome cyanine R tests: three agricultural species including wheat (Triticum aestivum L. and Triticum turgidum L.) and corn (Zea mays L.) and three wild species from the genus Sinapidendron. Profound differences in adaptation to local edaphic parameters (Al content, acidity, organic matter, altitude) between cultivated and wild species were observed. Comparison of the distribution patterns of the cultivated and wild species on the island may indicate that the anthropogenic activities played a pivotal role in the development of enhanced Al resistance among the cultivated species, while edaphic conditions seem to be a secondary factor.
- Ultrastructural and molecular characterization of a microsporidian infectingSerranus atricauda(Teleostei, Serranidae) in the Madeira ArchipelagoPublication . Casal, G.; Rocha, S.; Costa, Graça; Al-Quraishy, S.; Azevedo, C.
- Endoparasites of Trachurus picturatus (Pisces: Carangidae) from the Madeira and Canary Islands: selecting parasites for use as tagsPublication . Costa, Graça; Garcia Santamaria, Maria Teresa; Vasconcelos, Joana; Borges Perera, Clara; Moreira, Egberto MeloIn order to evaluate the use of parasites as biological tags to identify populations of the oceanic horse mackerel, Trachurus picturatus, two samples of 100 fish each, caught off the Madeira and Canary Islands from January to June 2009, were examined for the presence of anisakids, trypanorhynchs, acanthocephalans and liver coccidians. In T. picturatus from Madeira, prevalence of the coccidian Goussia cruciata reached 82%, whereas prevalence of the nematode Anisakis sp., the acanthocephalan Rhadinorhynchus cadenati and the trypanorhynch Nybelinia lingualis were 12.0%, 8.9% and 7.0%, respectively. In samples from the Canary Islands, prevalence of G. cruciata was 8.0%, Anisakis sp. and R. cadenati reached 5.0% and 42.0% respectively, and N. lingualis was not recovered. The absence of N. lingualis and the lower prevalence of Anisakis sp. appear to be related to the smaller size of the oceanic horse mackerels examined from the Canary Islands. Although significant differences in prevalence of two parasites, G. cruciata and R. cadenati, were found between the two regions investigated (χ2=125.13, df=1, p=0.000 and χ2=40.77, df=1, p=0.000), only G. cruciata was considered useful as a biological tag for the identification of populations of T. picturatus. In order to reach sound conclusions, an expansion of the temporal and spatial sampling strategy is recommended.
- Helminth parasites of Madeiran rockpool fishes, with a redescription of Schikhobalotrema longivesiculatum Orecchia & Paggi, 1975 (Digenea: Haplosplanchnidae), and some comments on their zoogeographical relationshipsPublication . Gibson, David I.; Costa, GraçaSeven species of Madeiran rockpool fishes were examined for their helminth parasites. Only two of these harboured helminth parasites. The most frequently encountered parasite was the digenean Schikhobalotrema longivesiculatum Orecchia & Paggi, 1975 from Parablennius parvicornis; this species is redescribed and discussed. The paucity of the parasite fauna of Madeiran rockpool fishes and the zoogeographical relationships of the digenean fauna of Madeiran marine fishes are commented upon.
- Larval cestodes infecting the deep-water fish, Cataetyx laticeps (Pisces: Bythitidae) from Madeira Archipelago, Atlantic OceanPublication . Costa, Graça; Khadem, Mahnaz; Dellinger, Thomas; Biscoito, Manuel; Moreira, Egberto MeloParasites of deep-water fishes are less known in comparison to the parasites of fishes living in the demersal and epipelagic ocean zones. In the present research note we report the occurrence of larval trypanorhynch cestodes in a rare deep-water fish, the deep-water brotula, Cataetyx laticeps. Based on the 28S rDNA (region D1-D3) sequence homology and the phylogenetic analysis, the larval cestodes are putatively assigned to the genus Grillotia. It is suggested that the definitive host of this trypanorhynch is a batoid.
- Gill monogeneans of the chub mackerel, Scomber japonicus from Madeiran waters of the Atlantic Ocean, PortugalPublication . Costa, G.; Freitas, N.; Dellinger, T. H.; MacKenzie, K.Five species of monogeneans were recovered from the gill filaments of 181 chub mackerel, Scomber japonicus, from the Madeiran waters of the Atlantic Ocean, Portugal, during 2004/2005. The monogenean Pseudokuhnia minor showed the highest prevalence (98.68%) and a mean intensity of 28.23, followed by Kuhnia scombri (prevalence of 43.71% and mean intensity of 2.69) and K. scombercolias (prevalence of 39.1% and a mean intensity of 1.81). Kuhnia sprostonae and Grubea cochlear were rare, occurring in only one and five fish hosts respectively. No correlation between fish host length and mean intensity of infection with the three most abundant monogeneans was found. However, significant differences in prevalence and abundance were found in relation to date of sampling for P. minor, and all parasites were aggregated in their distribution.
- Helminth parasites from the stomach of conger eel, Conger conger, from Madeira Island, Atlantic OceanPublication . Costa, Graça; Santos, Maria J.; Costa, Luísa; Biscoito, Manuel; Carvalho, Miguel Â. A. Pinheiro de; Moreira, Egberto MeloGeographic variations in the diversity and prevalence of helminth parasites of fish can provide important clues as to the relatedness of fish populations. In the present work, the stomachs of 64 conger eels, Conger conger, collected during 1999 and 2000, were examined for the presence of parasites. Four fish were infected with L3 stages of the nematode Anisakis simplex s.l. (Anisakidae), 1 with the nematode Cristitectus congeri (Cystidicolidae), 1 with the acanthocephalan Rhadi norhynchus pristis, 17 with postlarvae of Sphyriocephalus tergestinus (Eucestoda: Trypanorhyncha), and 55 with Lecithochirium spp. (Digenea: Hemiuridae). The hemiurids were the most abundant parasites, with a total of 385 individuals recovered. Strong aggregated distributions were found for both the digeneans, Lecithochirium musculus and Lecithochirium fusiforme, with variance-to-mean ratios (s 2 /x) and index of discrepancy (D) 13.98 and 0.672 (for L. musculus) and 8.08 and 0.90 for L. fusiforme, respectively. Intensity of L. musculus, L. fusiforme, and S. tergestinus showed significant relationships with depth of capture. Differences in number of species and prevalence were found between Madeira and the Atlantic coasts of the Iberian Peninsula.