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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.
- 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.
- Digenean parasites of the marine gastropods Littorina littorea and Gibbula umbilicalis in the Northern Portuguese Atlantic coast, with a review of digeneans infecting the two gastropod generaPublication . Costa, Graça; Soares, Sónia; Carvalho, Fernando; Bela, JoãoObjective: To study the digenean parasites of the prosobranch gastropods, Littorina littorea (L. littorea) and Gibbula umbilicalis (G. umbilicalis) from rocky shores of the Northern Atlantic coast of Portugal. Methods: A total of 413 L. littorea and 2603 G. umbilicalis were collected from rocky shores, at Aveiro estuary, Aguda Beach, and Foz Beach at Porto (Northern Atlantic coast of Portugal) from January to July 2014 and February 2014 to January 2015, respectively. Gonads and digestive glands of the gastropods were examined under light microscopy for the presence of digeneans. Infected gonads of L. littorea were prepared for histological observation, whereas digeneans found in G. umbilicalis were studied and identified with the aid of light and scanning electron microscopy. Results: Two species of digeneans were found infecting the digestive gland and gonads of G. umbilicalis, namely, Cainocreadium labracis and Lecithochirium furcolabiatum with a combined prevalence of 3%. Histological observations of gonads of L. littorea revealed the infection with digeneans, with considerable replacement of gonadal tissues. These digeneans were not identified to species level. The prevalence of digeneans in this snail host was 0.7%. Conclusions: The present study adds G. umbilicalis as another first intermediate host for Cainocreadium labracis and extends its geographical range to the Portuguese Atlantic coast. Cercariae of Lecithochirium furcolabiatum were previously reported from G. umbilicalis. A literature review of digeneans occurring in the gastropod genera Gibbula and Littorina is given.
- 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.
- Occurrence of microsporidians Glugea hertwigi and Pleistophora ladogensis, in smelt Osmerus eperlanus from two German rivers, North Sea coastPublication . Costa, G.; Moreira, E. Melo; Carvalho, M. A. P. deMonthly samples of smelt Osmerus eperlanus (Linnaeus, 1758) were collected from July 1985 to May 1986, in the river Elbe (Germany), and examined for infections with microsporidi ans. Two microsporidians were found: Glugea hertwigi Weissenberg, 1911, infecting the digestive tract and Pleistophora ladogenis Voronin, 1978, infecting the skeletal musculature. G. hertwigi in fection led to the formation of xenomas, whereas P. ladogensis was characterized by diffuse infec tions, with the production of macroscopic visible thread-like or oval-shaped infection foci. Develop ment of G. hertwigi in the host cells showed characteristics typical of the genus Glugea. The ultrastructural development of P. ladogensis showed features typical of the genus Pleistophora, without evidence of the production of 2 types of spores. Host reaction consisted of inflammatory tis sue surrounding some of the infection foci as well as phagocytosis of spores. G. hertwigi was only found in juvenile smelt (<10 cm in length), whereas P. ladogensis infected smelts from 6 to 26 cm in length. Prevalence increased with fish length to a maximum value of 9.6%. Seasonal fluctuations in prevalence of infection were also found, with the lowest value in the winter months (2.5% in January 1986) and the highest in summer (11.8% in July 1985). The differences in prevalence of in fection with fish length and date of sampling were significant. Additionally, samples of smelt caught in April 1986 from the rivers Eider and Ems revealed infections with P. ladogensis in the first river system only.
- 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.
- Endohelminth parasites of the leafscale gulper shark, Centrophorus squamosus (Bonnaterre, 1788) (Squaliformes:Centrophoridae) off Madeira ArchipelagoPublication . Costa, Graça; Chada, Tomás; Moreira, Egberto Melo; Cavallero, Serena; D’Amélio, StefanoThe endohelminth parasite fauna of a deep water shark, the leafscale gulper shark, Centrophorus squamosus, examined from Madeiran waters, from September 2009 to January 2010, consisted of larval and juvenile cestodes of two orders, namely Trypanorhyncha and Tetraphyllidea, and L3 stages of Anisakis spp. Infection with Anisakis spp. could be due to the shark’s opportunistic feeding on squids and black-scabbard fish, Aphanopus carbo, which is heavily parasitized by Anisakis spp. in Madeira waters. The occurrence of larval and juvenile cestodes only, in this shark, suggests that the leafscale gulper shark features as a paratenic or a dead-end host for the parasites.
- Cereal landraces genetic resources in worldwide GeneBanks. A reviewPublication . Carvalho, Miguel A. A. Pinheiro de; Bebeli, Penelope J.; Bettencourt, Eliseu; Costa, Graça; Dias, Sonia; Santos, Teresa M. M. dos; Slaski, Jan J.Since the dawn of agriculture, cereal landraces have been the staples for food production worldwide, but their use dramatically declined in the 2nd half of the last century, replaced by modern cultivars. In most parts of the world, landraces are one of the most threatened components of agrobiodiversity, facing the risk of genetic erosion and extinction. Since landraces have a tremendous potential in the development of new cultivars adapted to changing environmental conditions, GeneBanks holding their genetic resources potentially play an important role in supporting sustainable agriculture. This work reviews the current knowledge on cereal landraces maintained in GeneBanks and highlights the strengths and weaknesses of existing information about their taxonomy, origin, structure, threats, sampling methodologies and conservation and GeneBanks’ documentation and management. An overview of major collections of cereal landraces is presented, using the information available in global metadatabase systems. This review on winter cereal landrace conservation focuses on: (1) traditional role of GeneBanks is evolving beyond their original purpose to conserve plant materials for breeding programmes. Today’s GeneBank users are interested in landraces’ history, agro-ecology and traditional knowledge associated with their use, in addition to germplasm traits. (2) GeneBanks therefore need to actively share their germplasm collections’ information using different channels, to promote unlimited and effective use of these materials for the further development of sustainable agriculture. (3) Access to information on the 7.4 million accessions conserved in GeneBanks worldwide, of which cereal accessions account for nearly 45 %, particularly information on cereal landraces (24 % of wheat, 23 % of barley, 14 % of oats and 29 % of rye accessions), is often not easily available to potential users, mainly due to the lack of consistent or compatible documentation systems, their structure and registration. (4) Enhancing the sustainable use of landraces maintained in germplasm collections through the effective application of recent advances in landrace knowledge (origin, structure and traits) and documentation using the internet tools and data providing networks, including the use of molecular and biotechnological tools for the material screening and detection of agronomic traits. (5) Cereal landraces cannot be exclusively conserved as seed samples maintained under ex situ conditions in GeneBanks. The enormous contribution of farmers in maintaining the crop and landraces diversity is recognised. Sharing of benefits and raising awareness of the value of cereal landraces are the most effective ways to promote their conservation and to ensure their continued availability and sustainable use. (6) Evaluation of costs and economic benefits attributed to sustainable use of cereal landraces conserved in the GeneBanks requires comprehensive studies conducted on a case-by-case basis, that take into consideration species/crop resources, conservation conditions and quality and GeneBank location and functions.
- Morphological evaluation of common bean diversity on the Island of MadeiraPublication . Freitas, Gregório; Ganança, José F.T.; Nóbrega, Humberto; Nunes, Élvio; Costa, Graça; Slaski, Jan J.; Carvalho, Miguel Â. A. Pinheiro deThe variability of fifty populations of common bean (Phaseolus vulgaris L.), representing a wide range of ecological conditions on the Island of Madeira, was evaluated based on morphological and reproductive traits. Individual data of 58 traits related to earliness, plant and tassel structure and the shape of the ear and grain were analysed using multivariate analysis. The populations belonging to two major common varieties were clustered into fifteen groups by their degree of dissimilarity, based on discriminant analysis. The dissimilarity of these groups was con- firmed by one way ANOVA. The racial rank of these groups was proposed and a brief description of the common bean landraces was presented. This work represents the first morphological characterization and analysis of diversity of bean germplasm from the Archipelago of Madeira, where the traditional agricultural practices are still keeping this Portuguese region free from improved bean varieties. The description of the Madeiran bean landraces allows the preservation of the existing bean biodiversity and could be used for their registration as conservation landraces, or for conservation and breeding purposes worldwide.