The marbled crayfish (Procambarus virginalis) represents a very recently evolved parthenogenetic freshwater crayfish species that has invaded diverse habitats in Europe and in Madagascar. However, ...population genetic analyses have been hindered by the homogeneous genetic structure of the population and the lack of suitable tools for data analysis. We have used whole-genome sequencing to characterize reference specimens from various known wild populations. In parallel, we established a whole-genome sequencing data analysis pipeline for the population genetic analysis of nearly monoclonal genomes. Our results provide evidence for systematic genetic differences between geographically separated populations and illustrate the emerging differentiation of the marbled crayfish genome. We also used mark-recapture population size estimation in combination with genetic data to model the growth pattern of marbled crayfish populations. Our findings uncover evolutionary dynamics in the marbled crayfish genome over a very short evolutionary timescale and identify the rapid growth of marbled crayfish populations as an important factor for ecological monitoring.
The distribution and knowledge on the Mediterranean mantid Iris oratoria (Linnaeus, 1785) is here updated. Despite is beautiful appearance and presence in the social media, the scientific knowledge ...on its real distribution is poor and incomplete and this may affect its conservation at local scales. Citizen science records have been here compared with traditional science records, here updated with many new and original localities: this species is reported for the first time for Libya, Malta, Calabria and many Mediterranean islands and islets. The ecological preferences have been investigated in a retrodunal transect to investigate the preferred vegetation patterns for this species. The general value of citizen science records in evaluating the real distribution of a species have been tested here, using Iris oratoria as a case study for further investigations.
One of the most frequently translocated species outside their native range in Europe are water frogs of the genus
Pelophylax
. Recently, water frogs belonging to the same genus have also been ...recorded on the island of Gozo in Malta. To trace their origin, we genetically examined 17 individuals from three Gozitan localities where water frogs have been recorded recently. We analysed one mitochondrial (NADH dehydrogenase 2,
ND2
) and one nuclear (serum albumin intron 1,
SAI-1
) fragment to identify the geographic origin of the frogs and a set of microsatellite markers to determine their population-genetic structure and the predicted number of source populations. Based on the
ND2
and
SAI-1
markers, the water frogs on the island of Gozo originate from southern Anatolia, Turkey. According to sequence variation in
ND2
, they were assigned to a
caralitanus
mtDNA clade, which is endemic to southern Anatolia and taxonomically represents either an evolutionary lineage within
P.
cf.
bedriagae
or a separate species
P. caralitanus
. All Gozo water frogs had only one haplotype in the
ND2
and one allele in the
SAI-1
fragment, indicating a recent and single introduction event. These results are supported by microsatellite analysis, which revealed low genetic variability and the absence of any population-genetic structure, suggesting that Gozo water frogs originate from only one source population.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
In this study, we conducted a survey in the only Maltese marine cave (Ħarq Ħammiem) to assess the amphipod communities. The investigation revealed the first record of Neogammarus karamani (Stock, ...1971) for the Maltese archipelago and its eyeless habitus.
The expansion–contraction (EC) model predicts demographic and range contraction of temperate species during Pleistocene glaciations as a consequence of climate‐related habitat changes, and provides a ...paradigm for explaining the high intraspecific diversity found in refugia in terms of long‐term demographic stability. However, recent evidence has revealed a weak predictive power of this model for terrestrial species in insular and coastal settings. We investigated the Pleistocene EC dynamics and their evolutionary consequences on temperate species using the Maltese archipelago and its endemic lizard Podarcis filfolensis as a model system. The evolutionary and demographic history of P. filfolensis as inferred from mitochondrial and nuclear sequences data does not conform to the EC model predictions, supporting (i) demographic and spatial stability or expansion, rather than contraction, of the northern and southern lineages during the last glacial period; and (ii) a major role for allopatric differentiation primed by sea‐level dynamics, rather than prolonged demographic stability, in the formation of the observed genetic diversity. When combined with evidence from other Mediterranean refugia, this study shows how the incorporation of Pleistocene sea‐level variations in the EC model accounts for a reverse demographic and range response of insular and coastal temperate biotas relative to continental ones. Furthermore, this cross‐archipelago pattern in which allopatric diversity is formed and shaped by EC cycles resembles that seen between isolated populations within mainland refugia and suggests that the EC model, originally developed to explain population fluctuations into and out‐of refugia, may be appropriate for describing the demographic and evolutionary dynamics driving the high genetic diversity observed in these areas.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Esemplari di due specie di pesci non comuni, Schedophilus medusophagus e Petromyzon marinus, sono stati recentemente raccolti nelle acque dell'isola di Malta nel Mediterraneo centrale. Alcuni ...parametri morfologici e biologici degli esemplari sono descritti. I ritrovamenti accertano la presenza di queste due specie nell'area, corroborando inoltre l'importante contributo che i social media e i citizen scientists danno per quanto concerne le osservazioni in natura e quindi per un ulteriore incremento della conoscenza della biodiversità del Mediterraneo.
Invasive species can cause significant changes in local and regional ecologies, especially in freshwater ecosystems. It is thus important to monitor and document the spread of non-indigenous species ...to such habitats as such information can be critical to preserving habitats and species. We document the spread of the red swamp crayfish Procambarus clarkii (Girard, 1852) (Cambaridae), a highly invasive non-indigenous species, in Malta and south Sicily. We also document the first records of other non-indigenous decapods important in the pet trade or in aquaculture, Procambarus virginalis Lyko, 2017 (Cambaridae), Pontastacus leptodactylus (Eschscholtz, 1823) (Astacidae), Cherax quadricarinatus von Martens, 1868 (Parastacidae), Pacifastacus leniusculus (Dana, 1852) (Astacidae), and Atyopsis moluccensis (De Haan, 1849 (Atyidae) from freshwater localities in the Maltese Archipelago and Cherax destructor Clark, 1936 (Parastacidae) from southeastern Sicily. The study provides recommendations on the adoption of control measures by the competent national authorities with respect to these non-indigenous species.
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