Marco Casu

Università degli Studi di Sassari | UNISS · Dipartimento di Medicina Veterinaria

The BQ.1 SARS-CoV-2 variant, also known as Cerberus, is one of the most recent Omicron descendant lineages. Compared to its direct progenitor BA.5, BQ.1 has some additional spike mutations in some key antigenic sites, which confer further immune escape ability over other circulating lineages. In such a context, here, we perform a genome-based surve...

The genus Salariopsis (Blenniidae) comprises freshwater blenny fish that inhabits Mediterranean Sea, Black Sea, and north-east Atlantic areas. Three species were formally described to date: Salariopsis fluviatilis. S. economidisi, and S. atlantica. In this study, 103 individuals were collected from different Italian regions (Sardinia, Liguria, Pied...

This study aims to investigate the level of genetic variability of Fasciola hepatica flukes isolated from cattle in Algeria and to determine the phylogenetic and phylogeographic relationships with sequences isolated worldwide. Mitochondrial (Cytochrome c Oxidase subunit I gene - COI) and nuclear markers (Internal Transcribed Spacers of nuclear ribo...

Orf virus (ORFV) is distributed worldwide and is the causative agent of contagious ecthyma that mainly occurs in sheep and goats. This disease was reported for the first time at the end of 18th century in Europe but very little is currently known about the temporal and geographic origins of this virus. In the present study, the use of new Italian w...

Background Marine protected areas (MPAs) usually have both positive effects of protection for the fisheries’ target species and indirect negative effects for sea urchins. Moreover, often in MPAs sea urchin human harvest is restricted, but allowed. This study is aimed at estimating the effect of human harvest of the sea urchin Paracentrotus lividus...

Gyrodactylus sphinx Dmitrieva & Gerasev, 2000 is the only species of Gyrodactylus originally described from Aidablennius sphynx (Valenciennes) in the Black Sea. In the present study, monogeneans similar to G. sphinx are reported from the same host and from two other species of Blenniidae from the Black Sea, as well as from the Mediterranean Sea. Th...

Recent research hypothesised that the Siculo-Tunisian Strait might fit, at least for some species, the picture of a genetic transitional zone instead of a sharp genetic break between the Western and Eastern Mediterranean basins. The present study aimed at using the common Octopus, Octopus vulgaris as an empirical test-case to evaluate this hypothes...

Pinna nobilis is the largest bivalve of the Mediterranean Sea, where it represents a flagship species. As a possible consequence of several human disturbing activities, at the beginning of the ‘80s, populations of fan mussel started a severe demographic decline. To reverse this trend, P. nobilis was included in a regime of full protection which led...

I.A.); picossu@uniss.it (P.C.); gsesposito@uniss.it (G.E.); eantuofermo@uniss.it (E.A.); marcasu@uniss.it (M.C.) Abstract: The fan mussel, Pinna nobilis, represents the largest bivalve endemic to the Mediterranean Sea. Since 2016, dramatic mass mortality of this species has been observed in several areas. The first surveys suggested that Haplospori...

Whereas most work to understand impacts of humans on biodiversity on coastal areas has focused on large, conspicuous organisms, we highlight effects of tourist access on the diversity of microscopic marine animals (meiofauna). We used a DNA metabarcoding approach with an iterative and phylogeny-based approach for the taxonomic assignment of meiofau...

This study provides updated information on the distribution of the phlebotomine sand fly species and their genetic characterization in Sardinia, a Mediterranean island where leishmaniasis is endemic. From April to November 2017, sand flies were trapped in five different capture sites using sticky traps and light traps as collection methods, operate...

The cryptic diversity in the polychaete Syllis gracilis Grube, 1840, in the Mediterranean Sea was examined with an integrative morpho‐molecular approach. Individuals of S. gracilis were collected at eleven Mediterranean localities to provide an insight into the role of brackish environments in inducing cryptic speciation. The examination of morphol...

We used the cytochrome oxidase subunit I (coI) gene DNA to barcode 117 endemic Gulf and cosmopolitan Indo–West Pacific fish species belonging to 54 families and 13 orders. Novel DNA barcodes were provided for 18 fish species (Trachinocephalus sp., Nematalosa sp., Herklotsichthys lossei, Upeneus doriae, Trachurus indicus, Apogonichthyoides taeniatus...

Aquaculture finfish production based on floating cage technology has raised increasing concerns on the genetic integrity of natural populations. Accidental mass escapes can induce the loss of genetic diversity in wild populations by increasing genetic drift and inbreeding. Farm escapees likely represent an important issue in the gilthead sea bream,...

Background This study is the first contribution to the molecular taxonomy of Mesocestoides spp. from domestic and wild carnivores in the Mediterranean area. A total of 13 adult worms and 13 larval stages of Mesocestoides spp. were collected from domestic and wild carnivore hosts in Italy and Tunisia. Samples collected in the Slovak Republic were us...

The genus Alpioniscus Racovitza, 1908 (Trichoniscidae) from Sardinia is revised. Three new cave-dwelling species are described: A.onnisi Taiti & Argano, sp. n. , A.stochi Taiti & Argano, sp. n. , and A.sideralis Taiti & Argano, sp. n. . The genus Utopioniscus Schmalfuss, 2005 is considered to be a junior synonym of Alpioniscus , after morphological...

Five new species of Monocelididae (Platyhelminthes, Proseriata) are described from Eastern Atlantic. Three new Archilina species came from the Canary Islands. Two of them have the cirrus provided with a stylet, cylindrical in Archilina regina sp. nov. and spike-like in Archilina imperatrix sp. nov. Both species lack a vaginal pore: ventrally to the...

Ruditapes decussatus (Linnaeus, 1758) (Veneridae) is an Atlanto-Mediterranean bivalve whose populations have experienced reductions and, in some instances, hybridisation with allochthonous R. philippinarum. Acquisition of additional genetic knowledge concerning the present R. decussatus populations is essential to address adequate conservation plan...

Two new species of Otoplana (Proseriata: Otoplanidae) from the Canary Islands are here described: Otoplana norenburgi sp. nov. and Otoplana didomenicoi sp. nov. These new species are distinguished from their congeners by unique features of the sclerotized structures of the copulatory organ, in particular of the aculeus, swollen proximally in O. nor...

Since the opening of the Suez Canal in 1869 the Mediterranean Sea has been affected by a gradually increasing influx of species of Erythraean origin, which significantly modified species composition and ecological interactions of entire communities. Most studies have focused on macrofaunal species. Nevertheless, given the sandy nature of its shores...

Conservation of farm animal genetic resources is of fundamental importance for the study of the relationships among breeds. The aim of this study was to evaluate the usefulness of the nuclear fluorescence inter simple sequence repeat (FISSR) markers in order to shed light on the genetic biodiversity of domestic animals. Two modifications of the ori...

Representatives of the Meidiamidae and Otomesostomidae (Platyhelminthes: Proseriata) are seldom encountered, and the monophyly and phylogenetic relationships of these families have never been assessed on molecular basis. Here, we present the first exhaustive molecular study of Proseriata at the family level, including species belonging to the gener...

The survival of endangered and rare species with slow growth and low dispersal capabilities critically depends on the persistence of populations within marine protected areas (MPAs). The effectiveness of MPAs at maintaining the species evolutionary potential will depend on the occurrence of self-sustaining and viable populations, harboring sufficie...

Esox cisalpinus (Teleostea: Esocidae) (syn. Esox flaviae) is an Italian freshwater autochthonous fish, whose originary range is limited to the Northern and Central Italy. However, this species has historically been introduced in several areas of Southern Italy, mainly for recreational purposes. In this paper we report the first record of E. cisalpi...

The order Proseriata (Platyhelminthes) represents one of the most abundant soft-bodied meiofaunal groups. These minute interstitial organisms are characterized by a very simple morphology, which often hides the occurrence of cryptic species. Accordingly, molecular analyses are often needed to provide reliable taxonomic assessment and/or species ide...

Given the pending biodiversity crisis, species delimitation is a critically important task in conservation biology, but its efficacy based on single lines of evidence has been questioned as it may not accurately reflect species limits and relationships. Hence, the use of multiple lines of evidence has been portrayed as a means to overcome identific...

The Mediterranean Lessepsian migrations excite the interest of biologists who are devoted to inferring the effects of selection on the genetic structure of immigrants. The bluespotted cornetfish Fistularia commersonii is an Indo-Pacific species that was first recorded in the Levantine cost of Mediterranean, and within a few years, it rapidly expand...

Patterns of genetic variation in marine species reflect the interplay of species-specific traits, oceanographic features, historical processes and selection. In the Atlantic–Mediterranean regions, Patella ulyssiponensis (Mollusca: Gastropoda) was previously used as a model to investigate these patterns. Our study gained insight into the genetic pat...

Geminate species are a powerful tool for calibrating the molecular clock in marine organisms, and their adoption is mandatory for soft-bodied taxa, which lack fossil records. The first attempt to calibrate the molecular clock in taxa belonging to meiofaunal microturbellaria (Platyhelminthes: Proseriata) based on geminate species is presented here....

Four new species of Otoplanidae (Platyhelminthes: Rhabditophora: Proseriata) with ranges restricted to the central Mediterranean are described. These species are characterized by the presence of a tubular copulatory stylet and by a bursa lacking an open connection to the atrium. Both characters are novel for the family Otoplanidae. The four species...

Species of the genus Ophryotrocha are a well-studied group of organisms but, despite the relatively large body of biological studies, little is known about the intra-specific patterns of genetic diversity. In the present study, we analysed the patterns of genetic variation in samples of Ophryotrocha labronica (Polychaeta, Dorvilleidae) collected al...

Pinna nobilis is the largest endemic Mediterranean marine bivalve. During past centuries various human activities led to the regression of its populations. As a consequence of stringent protection policies (P. nobilis is included in Annex IV of the Habitat Directive and Annex II of the Barcelona Convention), demographic expansion to many sites is c...

Pinna nobilis is the largest endemic Mediterranean marine bivalve. During past centuries, various human activities have promoted the regression of its populations. As a consequence of stringent standards of protection, demographic expansions are currently reported in many sites. The aim of this study was to provide the first large broad-scale insig...

COI-16S dataset: network analysis. Median-joining network showing the haplotypes relationships among Pinna nobilis populations. Small red plots on the nodes, labelled as “mv”, show median vectors, representing hypothetic connecting sequences, calculated with a maximum parsimony method. Haplotypes diverge each other for a single mutation except wher...

COI, COI-16S, 16S datasets: genetic divergence estimates. Sample sizes and genetic diversity estimates obtained for the mitochondrial regions analysed in Pinna nobilis. N: sample sizes; S: number of polymorphic sites; H: number of haplotypes; h: haplotype diversity; π: nucleotide diversity; d: mean of pairwise nucleotide differences. Populations ar...

COI dataset: Bayesian COI haplogroup frequencies. N: absolute frequency; %: relative frequency within Mediterranean populations of Pinna nobilis. Populations are labelled as in Table 1. (DOC)

COI dataset: network analysis. Median-joining network showing the haplotypes relationships among Pinna nobilis populations. Small red plots on the nodes, labelled as “mv”, show median vectors, representing hypothetic connecting sequences, calculated with a maximum parsimony method. Haplotypes diverge each other for a single mutation except where Ar...

COI dataset: pairwise ΦST values among sampling localities. Pairwise ΦST values between Pinna nobilis populations with at least five individuals. Significance was assessed by permutation test. Significant values after correction for multiple testing are reported in bold. Populations are labelled as in Table 1. (DOC)

COI-16S dataset: haplotype frequencies. Frequency distribution of mitochondrial haplotypes in 244 individuals from 29 populations of Pinna nobilis. N: absolute frequency; %: relative frequency within Mediterranean populations. Populations are labelled as in Table 1. (DOC)

16S dataset: haplotype frequencies. Frequency distribution of haplotypes in 251 individuals from 29 populations of Pinna nobilis. N: absolute frequency; %: relative frequency within Mediterranean populations. Populations are labelled as in Table 1. (DOC)

COI-16S dataset: Bayesian COI-16S mitochondrial region haplogroup frequencies. N: absolute frequency; %: relative frequency within Mediterranean populations of Pinna nobilis. Populations are labelled as in Table 1. (DOC)

COI-16S dataset: pairwise ΦST values among samples localities. Pairwise ΦST values between Pinna nobilis populations with at least five individuals. Significance was assessed by permutation test. Significant values after correction for multiple testing are reported in bold. Populations are labelled as in Table 1. (DOC)

COI dataset: haplotype frequencies. Frequency distribution of COI haplotypes in 311 individuals from 34 populations of Pinna nobilis. N: absolute frequency; %: relative frequency within Mediterranean populations. Populations are labelled as in Table 1. (DOC)

This study provides data on the genetic structuring of the pipefish Syngnathus abaster in the western Mediterranean and Adriatic Seas. A total of 109 specimens were collected in brackish-water biotopes. The control region and three other regions of the mitochondrial genome were analysed. The most relevant result was the high genetic structuring fou...

The reproductive strategy of the simultaneous hermaphrodite Pseudomonocelis paupercula (Platyhelminthes: Proseriata) was investigated using multiple approaches including breeding experiments, anatomical reconstruc-tion, and parentage analysis of offspring. The 18 allozyme loci tested were monomorphic. Conversely, the ISSR markers showed differences...

The polychaete Hediste diversicolor is characterised by a high degree of genetic structure among populations. The genetic differentiation has been related to the presence of cryptic species, corresponding to Atlantic and Mediterranean lineages whose divergence may have been driven by vicariance and/or selection. In the present study we used DNA int...

Patella ulyssiponensis s.l. is widely distributed in the Mediterranean as well as in the north-eastern Atlantic, from southern Norway to north-western Africa, including Macaronesia. Throughout its range, P. ulyssiponensis s.l. shows a high degree of variability in the shape and colour pattern of the shell and in the colour pattern of the foot. In a...

Patella ferruginea Gmelin, 1791 is an endangered marine gastropod endemic to the Western Mediterranean. Its range is restricted to the Sardinian-Corsican region (SCR), North Africa, a few scattered sites in Southern Spain, and Sicily. Inter-simple sequence repeat (ISSR) markers and three different mitochondrial DNA (mtDNA) regions, Cytochrome c Oxi...

This study aims at comparing patterns of genetic diversity in farmed and wild populations of the gilthead sea bream, Sparus aurata Linnaeus, 1758 (Sparidae) along the Sardinian shores. We aimed at assessing if farmed populations are genetically divergent and have lower genetic variability than wild populations. As a by-product we investigated genet...

Syngnathus abaster is a euryhaline pipefish distributed in the Mediterranean, Black Sea, and the north-eastern Atlantic. Although its populations are characterised by high morphological plasticity, neither congruent information about the morphological differentiation of S. abaster populations from the Mediterranean lagoons is available, nor populat...

The bluespotted cornetfish (Fistularia commersonii) is an Indo-Pacific species that in the last ten years colonized a large part of the Mediterranean basin. The aim of this study was to sequence some portions of the mitochondrial DNA (D-loop II, 16S, 12S and Cyt b) of this fish from different localities of the Mediterranean Sea, in order to evaluat...

Pseudomonocelis paupercula nov. sp. is described from brackish-water habitats of the Mediterranean. It is distinguished from other members of the genus by the copulatory organ provided with a stylet, combined with lack of vagina and pres-ence of a muscular organ close to the female pore. Its phylogenetic relationships have been investigated sequenc...

Monocelis lineata is a complex of cryptic species (three in the Mediterranean and one in the Atlantic) widespread in midlittoral habitats. Throughout the range, populations with or without an ocular pigmented shield are found. We investigated the genetic structure of the North-East Atlantic populations with the aim of shedding light on their phylog...

The fan mussel Pinna nobilis Linnaeus, 1758 is one of the most endangered mediterranean bivalve. After a reduction of its distribution as a consequence of anthropic factors, the environmental politics led to a new demographic increasing of individuals in some Mediterranean regions. This work aimed to show some light on the genetic structure of two...

Patella ferruginea is an endangered marine gastropod, distributed on the western Mediterranean coasts, whose range has progressively contracted, due to intense human exploitation. A genetic analysis was performed on two unidentified young individuals belonging to the genus Patella found attached to the shell of an adult of P. ferruginea , with a tw...