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.
Since the XIX century, the systematics of the genus Tigriopus has been the object of several, sometimes contrasting, revisions about its diversity, taxonomy, and distribution and no consensus is to date available. In the frame of this work, the morphological and genetic diversity of Tigriopus fulvus in the Atlantic–Mediterranean area has been investigated, demonstrating that T. fulvus is the only Tigriopus species occurring in the study area. A restricted type locality is established for T. fulvus, and a neotype is designated.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
During the monitoring of Caretta caretta nests on the island of Linosa, 30 unhatched eggs from four nests were collected to study the presence of phthalates in their three components (shell, yolk, ...and albumen). Four phthalates, namely diethyl (DEP), dibutyl (DBP), di-(2-ethylhexyl) (DEHP), and dioctyl (DOTP) phthalic acid esters (PAE), which are widely used as additives in plastics, were detected in all egg components. The most frequently found phthalate was DBP, followed by DEHP in eggshell and yolk. Dimethyl- (DMP) and butylbenzyl-phthalate (BBP) were below the limits of detection for all samples. The high total phthalate recorded in the yolk suggests that contamination could arise by vitellogenesis. PERMANOVA analysis (p = 0.01) confirmed significant differences in the PAEs contamination profiles in the eggs from the four nests. This study confirms the negative impact of plastic related compounds posing questions about the potential adverse effects on organisms and their conservation status.
•Phthalates analyses showed contamination of Caretta caretta eggs.•Different total phthalates content was found in yolk, albumen, and eggshell.•Recorded levels of PAEs demonstrate the incidence of plastic-related pollution.
Biological invasions are known to be among the most important threats to the long-term conservation of native biota, and their effects might be even more difficult to contrast when they are cryptic, ...i.e., when the non-native invaders cannot be easily recognised based on morphology, and can thus be confused with native taxa. Such cryptic invasions are known to widely occur in the cladoceran genus Daphnia O.F. Müller, 1785, so that the actual distribution and status of most species and lineages need to be checked with a genetic approach. In the frame of this work, we investigated if the Sicilian populations of D. (Daphnia) pulex Leydig, 1860 belonged to the allochthonous North American lineage, which is known to occur in several regions of the Palearctic and Afrotropical biogeographical regions, or rather to the autochthonous European lineage of the species. The molecular results obtained, based on a fragment of the mitochondrial gene encoding for NADH subunit dehydrogenase 5 (ND5), allowed us to rule out the allochthonous status of the species, confirming the presence of autochthonous relictual lineages of D. pulex in Sicily. The native status of these populations is in agreement with their local distribution, limited to natural and poorly-impacted water bodies mostly located in wooded areas at medium and high altitudes. The current local distribution of D. pulex in Sicily is possibly linked to the end of the last glacial maximum and the onset of warmer climatic conditions in the early Holocene, which led the species to take refuge in colder microthermal refugia located at high altitudes, determining their current relictual distribution.
Although often considered primarily hematophagous on mammalian blood, the leeches belonging to the genus Hirudo can feed on several other vertebrate hosts. However, to date, little is known about the ...feeding ecology of medicinal leeches in the wild, and the few available observations mostly deals with the European medicinal leech, Hirudo medicinalis. Since even closely related Hirudo species have different functional morphology and ecological preferences, the observations carried out on one species cannot be automatically generalized to the other medicinal leeches, and targeted surveys must be realised to better understand the feeding habits of these leeches. A wide geographical belt ranging from the Iberian Peninsula to the Caucasus and Central Asia is inhabited by the southern European medicinal leech, Hirudo verbana. Although quantitative data are missing, the species seems characterized by a general decline throughout its distribution range, whose causes are not fully understood. Accordingly, a better understanding of H. verbana dietary composition is crucial to characterise its role in the trophic webs of the ecosystems it inhabits, with important consequences for the correct management of the populations of the species. Here, we report the observation of Hirudo verbana feeding on fish in the wild in southern Italy. This observation constitutes one of the first direct evidences of the species using fish as host organisms, since to date wild H. verbena had been observed mostly feeding on amphibians and mammals. Such information is useful to better characterise the diet of the wild populations of H. verbana, and to understand the trophic resources which could be exploited by the species in different ecosystems. Finally, a review of all the available evidence dealing with the use of fish as hosts organisms by Hirudo spp. is carried out.
The pond slider Trachemys scripta is one of the most widespread alien turtle species in the world. Its unregulated trade and the consequent uncontrolled releases into the wild led to negative impacts ...on the native turtles of the invaded areas. In Italy, alien pond sliders are widely spread, and the occurrence of hatchlings and well-established populations is known in some areas. However, to date in Sicily, only a single female of Trachemys scripta laying eggs was reported. Besides that, nothing is known about the actual reproduction success and establishment of self-sustaining T. scripta populations in Sicily. Therefore, based on 14 previously characterised highly polymorphic microsatellite loci, we aimed to unravel if the alien turtles successfully reproduce in Sicily, in both natural and semi-natural areas (i.e., lake “Biviere di Gela” and “Parco d’Orléans”, respectively). Our results show a clear structuring of the two studied populations. Several full-sibling relationships between the sampled turtles were found, suggesting actual reproduction in the wild of the pond sliders in Sicily. However, further sampling is desirable since no parent-offspring relationships were observed in the studied populations. Due to our results, systematic monitoring of alien pond sliders in the whole of Sicily is crucial for better planning of mitigation strategies in order to protect the native biota of Sicilian inland waters.
The Mediterranean area, from southern Balkans to western Maghreb, is inhabited by the Potamon subgenus Euthelphusa, with three currently recognised species. The Maghrebian species P. (E.) algeriense ...is isolated from other Potamon species by the Mediterranean Sea and the Sahara Desert, and nearly no molecular data are currently available for this taxon. Present study investigated the mtDNA and nuDNA diversity in Potamon algeriense s.l. with the aims of exploring its molecular diversity pattern throughout its known distribution range, and testing the possible presence of cryptic taxa currently lumped under this binomen. The phylogenetic and DNA taxonomy analyses showed the presence of two well‐supported clades of species rank within P. algeriense s.l, with an eastern clade including the populations from Tunisia and Numidia, and a western, highly structured clade including the populations from central Algeria and Morocco. In agreement with a typical Maghrebian biogeographic pattern, the distribution of these two species shows a clear east–west divide, with a disjunction zone located in Kabylia, and a strong link between molecular diversity and segregation within different hydrographical basins is evident. The Maghreb thus proved to host an unexpectedly high genetic diversity of, and to constitute a biodiversity hot‐spot for, the Potamon subgenus Euthelphusa. In the light of the existence of two well‐characterised species currently lumped under P. algeriense s.l., and of their noteworthy molecular structuring, the status of Maghrebian Potamon populations should be re‐assessed for both the species present in the area, which are to be considered as independent management units.
A dataset including novel and publicly available mtDNA COI sequences of 14 Mediterranean combtooth blenny species belonging to nine genera was assembled in order to provide a reference dataset for ...DNA barcoding studies. Some inconsistencies in the current taxonomy of some genera were observed. In particular, the monophyly of the genera Parablennius and Salaria is not supported by the present dataset and the absence of reciprocal monophyly between the morphospecies Salaria basilisca and S. pavo questions their status and stresses the need of a revision of the genus Salaria.
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