Summer aggregation of common eagle ray, Myliobatis aquila (Chondrichthyes: Myliobatidae), in the Marine Protected Area of the Egadi Islands (southwestern Tyrrhenian Sea)

We report for the first time in Italian waters a periodic and frequent presence of a summer aggregation of common eagle ray Myliobatis aquila in the island of Marettimo (southwestern Tyrrhenian Sea), which is part of the Marine Protected Area of the Egadi Islands. These aggregation could be related to different phenomena such as reproduction, feeding or simply as a transit zone

Growth and reproduction data of Plesionika narval (Decapoda, Caridea, Pandalidae) off the Island of Ustica (southern Tyrrhenian Sea)

We here report some data on the biology and population structure of Plesionika narval (Fabricius, 1787) captured along the coast of the island of Ustica in the southern Tyrrhenian Sea. Specimens were collected monthly from January to October 2000 using commercial traps at depths ranging from 15 to 100 metres. The carapace length (CL) of females ranged between 7.0 and 26.0 mm, and between 7.0 and 17.0 mm for males. Three modes were identified in the cumulative frequency distribution for females but only two for males. In females, the third modal value was observed only at the deeper sample sites. The Von Bertalanffy growth parameters and performance index ϕ were K = 0.65 y−1, CL∞ = 27.4 mm CL and ϕ = 2.62 for females, and K = 0.71 y−1, CL∞ = 17.8 mm CL and ϕ = 2.28 for males. Ovigerous females were found during the entire period of the investigation, indicating that this species spawns all year round. We compared our results with other data recorded in the literature

An account on the taxonomy and molecular diversity of a marine rock-pool dweller, Tigriopus fulvus (Copepoda, Harpacticoida)

The copepod genus Tigriopus Norman, 1869 is distributed worldwide in coastal rock pools and it is currently considered to include 14 valid species. Tigriopus fulvus (Fischer 1860), with its subspecies Tigriopus fulvus adriaticus Van Douwe 1913 and Tigriopus fulvusalgiricus Monard 1935, and Tigriopus minutus Bozic 1960 are currently reported to occur in the Mediterranean area, but the actual diversity of the genus is currently unknown. We aimed to assess the actual identity of Mediterranean Tigriopus populations and to elucidate their taxonomy and pattern of genetic diversity. In order to reach these goals, a fragment of a mitochondrial DNA gene (cytochrome c oxidase subunit I, COI) was sequenced to be used as a reference marker. Our data suggest the presence of a single species characterized by a noteworthy geographi-cally based genetic structure in the whole study area. The observed diversity pattern is tentatively ascribed here to a strong monopolization of the rock pools by the first immigrants that reached them. However, such a monopolization is periodically disrupted by local extinction events, which are frequent in the intrinsically unstable rock pool habitats. We propose the name “clockwork monopolization” for this pattern.El género de copépodos Tigriopus Norman, 1869 se distribuye en todo el mundo en charcas de rocas costeras y se considera que actualmente incluye 14 especies válidas. Tigriopus fulvus (Fischer 1860), con sus subespecies Tigriopus fulvus adriaticus Van Douwe 1913 y Tigriopus fulvus algiricus Monard 1935, y Tigriopus minutus Bozic 1960 han sido descritos para el área del Mediterráneo, pero la diversidad real del género es desconocida actualmente. El objetivo de este estudio fue evaluar la identidad real de las poblaciones mediterráneas de Tigriopus y dilucidar su taxonomía y patrón de diversidad genética. Con este fin, se secuenció un fragmento del gen de ADN mitocondrial (citocromo c oxidasa subunidad I, COI) como marcador de referencia. Los resultados sugieren la presencia de una sola especie caracterizada por una estructuración genética con una notable base geográfica en toda el área de estudio. El patrón de diversidad observado aquí se atribuye tentativamente a una fuerte monopolización de las charcas de las costas rocosas por parte de los primeros inmigrantes que las alcanzan. Sin embargo, tal monopolización se interrumpe periódicamente por los eventos de extinción local, los cuales son frecuentes en los hábitats de charcas de rocas que son intrínsecamente inestables. Aquí proponemos para este patrón el nombre de “monopolización periódica” (“clockwork monopolization”)

No evidence of DUI in the Mediterranean alien species Brachidontes pharaonis (P. Fisher, 1870) despite mitochondrial heteroplasmy

Two genetically diferent mitochondrial haplogroups of Brachidontes pharaonis (p-distance 6.8%) have been identifed in the Mediterranean Sea. This hinted at a possible presence of doubly uniparental inheritance in this species. To ascertain this possibility, we sequenced two complete mitogenomes of Brachidontes pharaonis mussels and performed a qPCR analysis to measure the relative mitogenome copy numbers of both mtDNAs. Despite the presence of two very similar regions composed entirely of repetitive sequences in the two haplogroups, no recombination between mitogenomes was detected. In heteroplasmic individuals, both mitogenomes were present in the generative tissues of both sexes, which argues against the presence of doubly uniparental inheritance in this species

The diaptomid fauna of Israel (Copepoda, Calanoida, Diaptomidae), with notes on the systematics of Arctodiaptomus similis (Baird, 1859) and Arctodiaptomus irregularis Dimentman & Por, 1985 stat. rev

Background: To date, only scarce information is available about the diaptomid copepods of the Middle East despite the ecological and biogeographical importance of the family Diaptomidae in the inland waters of the Holarctic region. Moreover, the taxonomic status of some of the taxa occurring in the area is in need of revision. We studied crustaceans collected from temporary and permanent lentic water bodies in Israel with the aim of providing an updated census of the diaptomid copepods occurring in the country. Furthermore, we morphologically and genetically analysed samples of Arctodiaptomus similis s.l. to shed light on its taxonomy. Results: Five diaptomid taxa were collected during this survey. Among these, Phyllodiaptomus blanci is new for the country and the whole circum-Mediterranean area and might be an allochthonous species of eastern origin. Within the collected samples, we singled out two parapatric groups of populations within A. similis s.l.; these consistently differ both based on morphology (chaetotaxy of the left male antennule) and molecular data (divergence over 17% at the mitochondrial gene for the cytochrome b). We thus attribute the full species rank to Arctodiaptomus irregularis Dimentman & Por, 1985 stat. rev., originally described as a subspecies of the widespread species Arctodiaptomus similis (Baird, 1859). Conclusions: We critically evaluated all species hitherto reported for Israeli inland waters. Considering both the confirmed literature data and the new findings, Israeli diaptomid fauna is composed of at least seven species. However, the need for further surveys in the Middle East and for detailed systematic revisions of some controversial taxa is stressed. Our results on the systematics of A. similis s.l. illustrate the importance of implementing molecular analyses when investigating diversity patterns of groups which are difficult to resolve based on morphology alone

Range‐wide phylogeography and taxonomy of the marine rock pools dweller Tigriopus fulvus (Fischer, 1860) (Copepoda, Harpacticoida)

In the light of the wide distribution and ecological importance of the genus Tigriopus in coastal rock pool habitats, and of its frequent use in aquaculture and as a model organism, we investigated the identity of the Atlantic–Mediterranean Tigriopus populations and elucidated their taxonomy and patterns of morphological and genetic diversity. In order to reach these goals, an "integrative taxonomy" multisource approach was implemented. First, we investigated the constancy and taxonomical value of the morphological characters currently used to distinguish among the Tigriopus species occurring in the Mediterranean and in Eastern Atlantic area north of the Tropic of Cancer, and checked the actual morphological differences possibly present among topotypical samples of Tigriopus fulvus fulvus (Fischer, 1860) and its two subspecies Tigriopus fulvus adriaticus Van Douwe, 1913 and Tigriopus fulvus algiricus Monard, 1935. Then, we sequenced fragments of mitochondrial (12S) and nuclear (28S) genes. In the frame of this study, different "DNA taxonomy" approaches were implemented in order to check whether the subspecies of Tigriopus fulvus were actually lineages evolving independently, that is, valid species according to the "evolutionary genetic species concept." The results coherently indicate the presence of a single species, characterized by constant morphology and a noteworthy geographically based genetic structure in the whole study area. No morphological or genetic support was found for the taxa of allegedly subspecific rank within T. fulvus, which are thus to be considered junior synonyms of T. fulvus s.s. Finally, a restricted locus typicus is established for T. fulvus, and a neotype is designated

Growth and reproduction of the deep-water rose shrimp, Parapenaeus longirostris (Lucas, 1846) (Decapoda, Penaeidae), in the southern Tyrrhenian sea.

From June 2006 to May 2007, monthly samples of Parapenaeus longirostris (Lucas, 1846) were collected on land from the landings of two different, although contiguous, fishing grounds exploited by the bottom trawl fisheries of the two fishing harbours of Terrasini and Porticello, located on the north-western coast of Sicily. Carapace length (CL) of the female and male deep-water rose shrimp in Terrasini ranged from 9 to 32 mm and 13 to 26 mm, respectively, whereas in Porticello the length ranged from 8 to 31 mm and 13 to 26 mm, respectively. The Von Bertalanffy Growth Function parameters for Terrasini females and males were CLoo = 38.5 mm, K = 0.65 year(-1) and CL infinity = 32.5 mm, K = 0.85 year(-1), respectively. For Porticello females and males, the parameters were CLoo = 40 mm, K = 0.60 year(-1) and CL infinity = 30 mm, K = 0.76 year(-1), respectively. Analysis of maturity stages indicates that the deep-water rose shrimp is an asynchronous batch of almost continuous spawners, although one to two peaks of activity can be detected. In both fishing areas, the reproductive phase peaked twice, once in January and again from August to September. The sizes at first maturity (CL50%) were 27.8 and 26.6 mm CL for Terrasini and Porticello, respectively

Overlooked cryptic endemism in copepods: Systematics and natural history of the calanoid subgenus Occidodiaptomus Borutzky 1991 (Copepoda, Calanoida, Diaptomidae)

Our comprehension of the phylogeny and diversity of most inland–water crustaceans is currently hampered by their pronounced morphological bradytely, which contributed to the affirmation of the ‘‘Cosmopolitanism Paradigm’’ of freshwater taxa. However, growing evidence of the existence of cryptic diversity and molecular regionalism is available for calanoid copepods, thus stressing the need for careful morphological and molecular studies in order to soundly investigate the systematics, diversity and distribution patterns of the group. Diaptomid copepods were here chosen as model taxa, and the morphological and molecular diversity of the species belonging to the west-Mediterranean diaptomid subgenus Occidodiaptomus were investigated with the aim of comparing the patterns of morphological and molecular evolution in freshwater copepods. Three species currently lumped under the binomen Hemidiaptomus (Occidodiaptomus) ingens and two highly divergent clades within H. (O.) roubaui were distinguished, thus showing an apparent discordance between the molecular distances recorded and Occidodiaptomus morphological homogeneity, and highlighting a noteworthy decoupling between the morphological and molecular diversity in the subgenus. Current Occidodiaptomus diversity pattern is ascribed to a combined effect of ancient vicariance and recent dispersal events. It is stressed that the lack of sound calibration points for the molecular clock makes it difficult to soundly temporally frame the diversification events of interest in the taxon studied, and thus to asses the role of morphological bradytely and of accelerated molecular evolutionary rates in shaping the current diversity of the group

Foreword to the special issue "new frontiers for monitoring European biodiversity: The role and importance of amphipod crustaceans"

[No abstract available