Search results for "teleostei"
showing 10 items of 26 documents
A New Species of Ligophorus (Monogenea: Dactylogyridae) from the gills of the Flathead Mullet Mugil cephalus (Teleostei: Mugilidae) from Mexico
2015
AbstractA new monogenean species, Ligophorus yucatanensis n. sp. from the gills of the flathead mullet Mugil cephalus from the Yucatan Peninsula, Mexico, is described. The new species can be differentiated from all other species of Ligophorus by the morphology of the accessory piece of the copulatory organ. Its main lobe is cylindrical, tunnelled expanded distally, slightly bowed with a characteristic membranous opening at level of medial bifurcation of the accessory piece, forming a thick-walled bulbshaped expansion that ends in a round labium. The secondary lobe is spatulate, straight, and shorter than the main lobe. In addition, the new species can be distinguished from other species by …
Myxobolus albin. sp. (Myxozoa) from the Gills of the Common GobyPomatoschistus micropsKrøyer (Teleostei: Gobiidae)
2009
A recent investigation into the myxozoan fauna of common gobies, Pomatoschistus microps, from the Forth Estuary in Scotland, revealed numerous myxosporean cysts within the gill cartilage. They were composed of polysporous plasmodia containing myxobolid spores that were morphologically different from the other known species of Myxobolus and from the myxosporeans previously recorded from this host (i.e. the ceratomyxid Ellipsomyxa gobii, infecting the gall bladder, and the kudoid Kudoa camarguensis, infecting the muscle tissues). Spores were ovoid, 9.4 x 9.1 microm with a thickness of 6.6 microm, with two pyriform polar capsules, the polar filaments of which had four to five turns. Molecular …
Species complexes and phylogenetic lineages of Hoferellus (Myxozoa, Cnidaria) including revision of the genus: A problematic case for taxonomy
2015
Background Myxozoans are metazoan parasites whose traditional spore morphology-based taxonomy conflicts DNA based phylogenies. Freshwater species of the genus Hoferellus are parasites of the excretory system, with several members infecting food and ornamental fish species, as well as amphibians. This study aims to increase our understanding of their molecular diversity and development, aspects about which little is known, and to generate a molecular diagnostic tool to discriminate between different pathogenic and non-pathogenic Hoferellus spp. Methods SSU and ITS rDNA phylogeny, along with morphological descriptions using light and electron microscopy were used to identify and characterize …
Cardicola aurata sp. n. (Digenea: Sanguinicolidae) from Mediterranean Sparus aurata L. (Teleostei: Sparidae) and its unexpected phylogenetic relation…
2008
A new sanguinicolid trematode, Cardicola aurata sp. n., is described from gilthead seabream Sparus aurata L., from off the Spanish Mediterranean coast. The morphology of C. aurata sp. n. generally agrees with the diagnosis of the genus, however, in contrast to all other reported Cardicola spp. the male pore is located sub-medially at the posterior end of the body instead of sinistrally before the posterior end of the body. Based on a comparison of the morphology as well as partial 28S and ITS2 rDNA sequence data from the present species with that from closely related species, it was decided to emend the diagnosis of Cardicola rather than create a new genus, as the aberrant position of the m…
Diet of Phycis blennoides (Gadidae) in Relation to Fish Size and Season in the Western Mediterranean (Spain)
2002
. Despite its commercial value, little is known about the feeding ecology of the greater forkbeard, Phycis blennoides (Brunnich 1768). The stomach contents of 2631 greater forkbeard were taken at monthly intervals off the coast of the Gulf of Valencia (western Mediterranean). They were examined in order to assess the diet and to determine the fish size- and season-related dietary variation of the species. Prey items were identified to the lowest taxonomic level possible. The basic food consisted of epibenthic species, mostly Decapoda, Mysidacea and Teleostei. A change in food composition based on fish size was observed and seasonal variation in diet was also recorded. The food overlap analy…
DESCRIPTION AND MORPHOMETRICAL VARIABILITY OF A NEW SPECIES OF LIGOPHORUS AND OF LIGOPHORUS CHABAUDI (MONOGENEA: DACTYLOGYRIDAE) ON MUGIL CEPHALUS (T…
2006
A comparative morphological study of specimens of Ligophorus spp. from Mugil cephalus in western Mediterranean and the Black Sea localities has been carried out, indicating the presence of 2 distinct forms, i.e., Ligophorus chabaudi and Ligophorus cephali n. sp. A detailed description of the latter and an up-to-date redescription of L. chabaudi are provided. The existence of these 2 morphological species was additionally supported by principal component analysis based on 19 metric characters of 87 specimens arranged in samples defined by parasite species and geographical locality. The analysis indicated consistent differences between species but not between localities; this pattern was well…
Capillostrongyloides morae sp. n. (Nematoda: Capillariidae) from deep-sea fish (Teleostei, Moridae) in the western Mediterranean Sea
2014
A new capillariid nematode, Capillostrongyloides morae sp. n., is described from specimens collected from the stomach and intestine of the common mora, Mora moro (Risso), and the Mediterranean codling, Lepidion lepidion (Risso) (both Gadiformes, Moridae), off the Mediterranean coasts of Spain. The new species shows similar morphological features as other congeneric species occurring in freshwater and marine fishes, but it differs in the length of the body and spicules, the size of the caudal bursa, and the presence of an elevated anterior vulvar lip. Capillostrongyloides morae sp. n. is the second species within the genus for which the presence of a stylet is reported, and the first one in …
Within-lake dynamics in the similarity of parasite assemblages of perch (Perca fluviatilis).
2005
Although parasite communities have been studied extensively in recent years, spatial and temporal variation in factors affecting the communities has received less attention. This paper examined the similarity of parasite assemblages of perch (Perca fluviatilis) in 18 locations within a single lake in relation to geographical distance and temporal dynamics in the host and parasite populations. We expected that in the present study-scale where distinct but potentially interacting host subpopulations could occur, similarity of the assemblages could be affected by seasonal dynamics in host movements particularly during the spawning period. Parasite species showed differences in infection levels…
Chemiluminescence response of ß-glucan stimulated leukocytes isolated from different tissues and peritoneal cavity of Dicentrarchus labrax
2003
Abstract The respiratory burst of leukocytes isolated from sea bass ( Dicentrarchus labrax ) pronephros, peritoneal cavity (P.C.), spleen and blood, was measured by a chemiluminescence (CL) assay after stimulation with β-glucan. The CL response by P.C. and pronephros leukocytes was significantly higher than that expressed by a similar number of cells separated from spleen and blood. This probably reflects the observation that the proportion of macrophages and neutrophils was highest in the populations of leukocytes from peritoneal cavity and pronephros. Comparative observations showed a higher degree of yeast phagocytosis by leukocytes taken from peritoneal cavity than the pronephros. Moreo…
Multiple chromosome polymorphism in the gobiid fish Gobius niger jozo L. 1758 (Pisces, Gobiidae).
1989
By analysing chromosome preparation from 42 Gobius niger jozo specimens from the Gulf of Palermo (Sicily), four different karyotypes were observed: A (2n=52; NF=60), B (2n=51; NF=60), C (2n=50; NF=60) and D (2n=49; NF=60). A chromosome polymorphism due to Robertsonian fusion is present in this species.