[show abstract][hide abstract] ABSTRACT: Protogynous sequential hermaphroditism is very common in marine fish. Despite a large number of studies on various aspects of sequential hermaphroditism in fish, the relationship between body shape and colour during growth in dichromatic species has not been assessed. Using geometric morphometrics, the present study explores the relationship between growth, body shape and colouration in Coris julis (L. 1758), a small protogynous labrid species with distinct colour phases. Results show that body shape change during growth is independent of change in colour phase, a result which can be explained by the biology of the species and by the social control of sex change. Also, during growth the body grows deeper and the head has a steeper profile. It is hypothesized that a deeper body and a steeper profile might have a function in agonistic interactions between terminal phase males and that the marked chromatic difference between colour phases allows the lack of strict interdependence of body shape and colour during growth.
Environmental Biology of Fishes 08/2013; 94(4). · 1.31 Impact Factor
[show abstract][hide abstract] ABSTRACT: A multibiomarkers approach was used in order to estimate and monitor marine pollution. Coris julis (Linneaus, 1758) was chosen as a sentinel organism, and the specimens were collected from three well-known sites along the Ionic coast of Sicily: the protected marine area (P.M.A) "Cyclop's Islands" of Acitrezza (CT), used as a control site, Riposto (CT), and the industrial site of Augusta (SR). Abiotic levels of contaminants were also detected. High levels of biotic and abiotic accumulation were found at the industrial site in which the presence of genotoxic and oxidative damage were also evidenced, measured by Micronuclei, Alkaline and Fpg-modified Comet assays. The protein expression analysis showed metallothioneins (MTs) as good tissue-specific markers of metal accumulation. Their levels were significantly higher in muscle than in liver tissue for all the sampling sites, with a positive correlation among tissue levels and the degree of pollution at the sites. Conversely, heat shock proteins 70 (HSP70) expression was higher in Augusta and Riposto than in the control site, but no significant difference was found between the examined tissues among all sites.
Ecotoxicology and Environmental Safety 09/2012; · 2.20 Impact Factor
[show abstract][hide abstract] ABSTRACT: Sequence variation in the mitochondrial control region was studied in the Mediterranean rainbow wrasse (Coris julis), a species with pronounced pelagic larval phase inhabiting the Mediterranean Sea and the adjacent coastal eastern Atlantic
Ocean. A total of 309 specimens from 19 sampling sites were analysed with the aim of elucidating patterns of molecular variation
between the Atlantic and the Mediterranean as well as within the Mediterranean Sea. Phylogeographic analyses revealed a pronounced
structuring into a Mediterranean and an Atlantic group. Samples from a site at the Moroccan Mediterranean coast in the Alboran
Sea showed intermediate frequencies of “Mediterranean” and “Atlantic” haplotypes. We recognised a departure from molecular
neutrality and a star-like genealogy for samples from the Mediterranean Sea, which we propose to have happened due to a recent
demographic expansion. The results are discussed in the light of previous studies on molecular variation in fish species between
the Atlantic and the Mediterranean and within the Mediterranean.
[show abstract][hide abstract] ABSTRACT: Nine populations of Aphanius
fasciatus Nardo, 1827 from the central Mediterranean were analysed by examining the mitochondrial control region and the morphology of the bony elements of the skull and vertebral column, to study the degree of intraspecific differentiation of A. fasciatus considering the level of isolation of the different populations and the palaeogeographic history of the central Mediterranean area. Both the molecular and morphological analyses differentiate between the populations, even if the topologies of the two trees are different. Molecular and osteological investigations have consistently demonstrated a well-supported differentiation of the south-eastern Sicilian populations both within the same group (Tigano et al. in Ital J Zool 71:1124–1133, 2004a; Tigano et al. in Abstract volume XI European Congress of Ichthyology, Tallin, Estonia, 2004b), and from the populations from western Sicily, Tunisia and the island of Malta. The molecular results show that the nine populations are characterised by haplotypes that are well defined in relation to a probably limited gene flow; while, as regards the morphological data the differentiation found could be explained in terms of the geographic isolation of the various populations, although the influence of environmental factors, which differ greatly between the various sites where the populations live, cannot be ruled out.
[show abstract][hide abstract] ABSTRACT: In the present study, variation in the morphology of the lower pharyngeal element between two Sicilian populations of the rainbow wrasse Coris julis has been explored by the means of traditional morphometrics for size and geometric morphometrics for shape. Despite close geographical distance and probable high genetic flow between the populations, statistically significant differences have been found both for size and shape. In fact, one population shows a larger lower pharyngeal element that has a larger central tooth. Compared to the other population, this population also has medially enlarged lower pharyngeal jaws with a more pronounced convexity of the medial-posterior margin. The results are discussed in the light of a possible more pronounced durophagy of this population.
Italian Journal of Zoology 09/2011; 78(3):320-327. · 0.89 Impact Factor
[show abstract][hide abstract] ABSTRACT: The microstructure of the anterior region of the scales in several species of the genus Aphanius was studied by SEM with the aim of determining whether scale morphology could be used to discriminate between the species of this genus. The characters examined concern the morphology of lepidonts, or “scale‐teeth”, their distribution and mode of implantation on the circuli. These characters were also subjected to UPGMA cluster analysis. Results from phenetic analysis of scale‐teeth characters agree overall with those of previously published morphological and biogeographical studies and in part with molecular analysis of the phylogenetic relationships between species of Aphanius. An affinity between A. danfordii and A. mento (found previously in studies based on osteological observations) was seen. The separation of A. apodus from the other species of the fasciatus group, which had also been noticed from molecular observations, was also observed, as well as the affinity of A. ginaonis with the group of A. dispar+A. sirhani. This study demonstrates that scale morphology can provide useful information on the relationships among species of the genus Aphanius encouraging the use of scale characters, combined with other traits, in phylogenetic analyses.
Italian Journal of Zoology 06/2009; 76(2):173-178. · 0.89 Impact Factor
[show abstract][hide abstract] ABSTRACT: The blenny Parablennius sanguinolentus was selected as a useful bioindicator of environmental pollution. Chemical parameters in water and sediments from three different sampling sites along the Sicilian Ionian coast were determined and metal concentrations in fish muscle were measured. DNA fragmentation and oxidation in erythrocytes and hepatocytes was determined by the Comet assay and HSP70 expression levels were evaluated in the liver. The results show an increased level of chromium in sediments and high polycyclic aromatic hydrocarbon (PAH) concentrations in water at one site. The bioaccumulation of metals in muscle tissue shows high concentrations of lead in some samples. A high percentage of DNA damage in blood and liver cells, as well as high hepatic levels of HSP70, were found in all the sites. The results demonstrate the usefulness of an integrated chemical and biological approach for the determination of environmental stress.
Ecotoxicology and Environmental Safety 03/2009; 72(4):1278-86. · 2.20 Impact Factor
[show abstract][hide abstract] ABSTRACT: Aphanius fasciatus is a cyprinodont distributed in the salty coastal water of the central and eastern Mediterranean Sea and occasionally in internal fresh water. In this work, the authors have investigated the genetic structure of eight populations of the killifish A. fasciatus from Sardinia and Sicily. The comparison of the mtDNA control region of 237 individuals revealed a total of 49 haplotypes. Several unique haplotypes were present in each population, and no common haplotype was found among Sicilian and Sardinian populations. Almost all Sardinian populations shared a common haplotype, and indeed the four Sicilian populations examined did not share any as determined by the parsimony network analysis. The analysis of molecular variance showed that the percentage of variation among populations is much higher than within each population of A. fasciatus. The overall FST value is very high (0·78) and supports an extensive genetic structure of the populations. The observed genetic differentiations of A. fasciatus populations were discussed taking into account the palaeogeographic and palaeoclimatic events that interested the Mediterranean area from Miocenic to Pleistocenic age. The results provide new insight into the knowledge of the pattern of genetic structure and of evolutionary processes occurring in this species.
Journal of Fish Biology 03/2008; 72(5):1154 - 1173. · 1.83 Impact Factor
[show abstract][hide abstract] ABSTRACT: Due to the natural fragmentation of its habitats, Aphanius fasciatus, a Cyprininodontid living in coastal brackish‐water habitats, is distributed discontinuously with considerable isolation of its populations, and characterized by a high degree of osteological and genetic differentiation among them. The genetic relationships in four different Italian populations were studied using the control region (D‐loop) mitochondrial DNA sequence and the polymorphisms generated by RAPD‐PCR. The results revealed a well‐defined genetic structuring, that was also confirmed by the high Gst and Fst values, and a close relationship between the populations of Ganzirri and Lesina, as well as the isolation of the other two Sicilian populations. Moreover, with respect to the mitochondrial DNA analyses, the total genetic variance was higher among populations, but lower in the case of the RAPD polymorphisms.
Italian Journal of Zoology 12/2007; 74(4):371-379. · 0.89 Impact Factor
[show abstract][hide abstract] ABSTRACT: Two species of Blennies--Salaria fluviatilis, which lives in freshwaters, and Salaria pavo, which lives in the sea--are considered to be phylogenetically related. Due to the interesting feature of one species having a freshwater and one having a marine habitat, and because of the paucity of studies on the intraspecific and interspecific variability of skeletal characters, in the study reported here, several populations of S. fluviatilis and S. pavo were compared. The intraspecific and interspecific morphology of the cranial characteristics, as well as the branchial epithelium, was studied in relationship to the adaptation of the two species to different environments. Osteological results confirmed the intraspecific variability already found in S. fluviatilis and showed a notable interspecific differentiation between S. pavo and S. fluviatilis. Histological studies indicate that the two species have morphological differences, which are the result of the diversity of the environments in which they live. The results from the two approaches, taken together, are in agreement with the hypothesis of the origin of these two species being from a common marine ancestor.
[show abstract][hide abstract] ABSTRACT: The amount of osteological variation among 11 Italian killifish Aphanius fasciatus populations was examined by the univariate and multivariate analysis of 40 morphometric and meristic variables of the skull and vertebral column. Populations were sampled in three geographically distinct areas (the Adriatic, Sardinia and Sicily). The statistical analysis confirmed that several populations were well differentiated. In particular, discriminant analysis revealed a strong discriminating power of the morphometric variables. Morphometrics of the vertebrae, bony elements of the pharyngeal jaws, supraoccipital and parasphenoid were the most important in discriminating populations. The dendrogram obtained by UPGMA cluster analysis shows the separation of the south-eastern Sicilian populations, that of the Sardinian populations and that of the central-northern Sicilian plus Adriatic populations, as well as the isolation of the Sicilian population from Pantano Viruca and of the Sardinian populations from Pauli Figu from all the others. The significance of the observed differentiation pattern is discussed.
Journal of Fish Biology 01/2007; 70(1):1 - 20. · 1.83 Impact Factor
[show abstract][hide abstract] ABSTRACT: The first set of eight polymorphic microsatellites markers was successfully optimized from a partial genomic library enriched for an AC motif of the killifish Aphanius fasciatus Nardo, 1827 (Teleostei, Cyprinodontidae), a brackish-water fish widely distributed along the coasts of the Mediterranean Sea. The developed loci proved to be polymorphic, dis-playing from two to six alleles per locus with expected heterozygosity ranging from 0.277 to 0.752. All loci were under Hardy–Weinberg equilibrium, except Af8 that showed signif-icant heterozygotes deficiency, and there was no evidence of linkage associations between any pair of loci. Markers reported here will be potentially useful in monitoring of genetic population structure in this species.
[show abstract][hide abstract] ABSTRACT: Chromosome location of major (18S, 5.8S and 28S) and 5S ribosomal RNA genes (rDNAs) was examined in Lebias fasciata collected from different Italian blackish-waters, using silver (Ag)- and chromomycin A3 (CMA3)-staining and/or fluorescence in situ hybridization (FISH). Both 18S and 5S rDNA probes for FISH were obtained with polymerase chain reaction-directed cloning from genomic DNA of the examined species. Nucleolar organizer regions (NORs) containing the major rDNAs showed intraspecific polymorphism in number as detected by Ag-and CMA3-staining and FISH with the 18S rDNA probe. On the other hand, 5S rDNA loci constantly occurred on one chromosome pair and co-localized with a pair of the major rDNA loci as evidenced by two-color FISH using the 5S and 18S rDNA probes. Sequential CMA3- and Ag-NOR staining and FISH revealed apparent inactivation of some NORs. The cloned 5S rDNA was found to contain some TATA-like sequences that might play an important role in the regulation of gene expression.
[show abstract][hide abstract] ABSTRACT: The study of three Sicilian populations of Aphanius fasciatus was carried out by examining the mitochondrial control region and the morphology of the bony elements of the skull and vertebral column. The osteological and molecular data obtained indicate a marked differentiation between the populations examined resulting from their isolation, even if the dendrograms of the two approaches are dissimilar. Molecular investigations show that populations are characterized by haplotypes that are well defined in relation to the limited gene flow; while the osteological investigation may account for appreciable environmental influences on the morphological characters.
Italian Journal of Zoology 01/2004; 71(2):107-113. · 0.89 Impact Factor
[show abstract][hide abstract] ABSTRACT: The microstructure of the scale surface was analysed in five species of the genus Lebias, Goldfuss by scanning electron microscopy. The morphology, the disposition and type of attachment of the lepidonts on the crest of the circuli, found at the anterior portion of the scales, allowed us to identify a high affinity between L. dispar and L. sirhani and a pronounced morphological gradient from L. fasciata to L. iberus and L. apoda, with the latter being well differentiated with respect to the others. The results agree with morphological data that are already known for the five species examined.
Journal of Natural History - J NATUR HIST. 01/2003; 37(12):1529-1534.
[show abstract][hide abstract] ABSTRACT: Histochemical and immunohistochemical techniques were used to investigate the effect of stress from heavy metals on the respiratory epithelia of the cyprinodont Lebias fasciata living in confined natural environments with different degrees of pollution (brackish swamps of Faro‐Ganzirri and Lesina). This effect was evaluated on cytokeratins and calcium‐binding proteins, with particular reference to the presence of neuronal nitric oxide synthase in the cells of the diffuse neuroendocrine system (DNS). A morphometric examination was also performed to identify possible cranio‐facial and vertebral anomalies; however, the results were negative for all specimens from the two environments. Regarding the presence of heavy metals, only slight differences were found between the two environments, except for the higher concentration of aluminum in the Lesina swamp. In the gills of individuals from the latter environment, the epithelium presented a morphologically and immunohistochemically modified structure, with a concomitant over‐production of mucus; this acts as a barrier to oxygen diffusion, causing strong hypoxia. Therefore, it is hypothesized that the high number of DNS cells and nerve fibers im‐munopositive to nNOS in the respiratory epithelium of Lebias fasciata specimens from lesina is a local reaction to hypoxia.
Italian Journal of Zoology 01/2002; 69(3):195-203. · 0.89 Impact Factor
[show abstract][hide abstract] ABSTRACT: The degree of osteological differentiation of the pharyngeal and oral jaws in five populations of Lebias fasciata was studied. Fourteen morphometric and meristic osteological characters were examined. The results allowed us to differentiate the five populations of L. fasciata and particularly that of Manzonara, living in the Salso river and showing a more evident osteological differentiation. It is probable that the observed morphological differentiation among populations of L. fasciata could be a result of their isolation and that the characters examined could represent partially or totally fixed genetic adaptations.
Italian Journal of Zoology 01/2001; 68(3):201-206. · 0.89 Impact Factor
[show abstract][hide abstract] ABSTRACT: A preliminary study on nucleolus organizer region polymorphism was carried out in a Sicilian population of Lebias fasciata using several staining techniques (Ag‐staining, CMA3‐staining, and FISH). Intrapopulation polymorphism of the number and size of the rDNA loci was found. A maximum of six NORs was found, involving four chromosome pairs both in homozygotic and het‐erozygotic conditions. Duplication of NORs was also detected.
Italian Journal of Zoology 01/2000; 67(3):269-272. · 0.89 Impact Factor