Cockroach (Blattodea, Blaberoidea) fauna of the Maltese Islands, with descriptions of two new species.

Cockroach (Blattodea, Blaberoidea) fauna of the Maltese Islands. Hitherto seven species of cockroaches were known from the Maltese Archipelago (Schembri 1980): four of them are synanthropic species introduced by man: Blatta orientalis, Blattella germanica, Periplaneta americana and Supella longipalpa; the remaining three are indigenous species: Ectobius kraussianus, Loboptera decipiens and Polyphaga aegyptiaca. The earlier reports almost exclusively concern the largest island Malta; only one report (L. decipiens) applies to the islet Comino. Faunistic part. By recent collectings of the authors (mainly A.S.) including also the smaller islands Gozo, Comino and some rock islets (Cominotto, Filfla, Fungus Rock, Large Blue Lagoon Rock, Pigean Rock) the known distribution of the species could be largely widened; two further obviously indigenous species were found, both new to science and presumably endemic to Malta: Ectobius melitensis, sp. nov. (Ectobiidae, Ectobiinae) and Heterogamisca jeffreyana, sp. nov. (Corydiidae, Corydiinae). E. kraussianus presumably has to be eliminated from the list of Maltese cockroaches; the older report most likely concerns a misidentified E. melitensis. During the last years the number of introduced species was strongly increased (1) by escapees of species cultivated for the nourishment of amphibia and reptilia, as are Blaptica dubia, Gromphadorhina sp., Nauphoeta cinerea, Periplaneta fuliginosa, Shelfordella lateralis and Symploce pallens, and (2) by species presumably imported with gardening materials: Pycnoscelus surinamensis and Phoetalia pallida. The mentioned species have repeatedly been found in human buildings and adjacent gardens of a number of settlements, mostly in the surroundings of the capital Valetta. They seem to be well established there; part of them has even been observed in the wild. The newly introduced species are in spite of their successful establishment and reproduction in Malta not considered as a danger for the indigenous species: The great differences in the requirements between the two groups most likely exclude competition between them. Three species, Ectobius vittiventris, Henschoutedenis flexivitta, and Periplaneta australasiae, have only occasionally been found and can, therefore, scarcely be considered as members of the Maltese fauna; the latter also applies to species of the genus Panchlora which were repeatedly observed on fruit markets at freshly imported bananas, but never found outside, neither in the Maltese banana plantations. Taxonomic part. The new species are described and compared with their closest relatives, colouration and characteristic structures are shown in several figures. Ectobius melitensis belongs to the kraussianus-species group of Ectobius known from Sicily and surrounding islands (Ustica, Aeolian Islands, Ponza), but with one species also reaching Albania; the nearest relatives of Heterogamisca jeffreyana are occurring on the Iberian Peninsula and North Africa (Morocco, Algeria, Tunisia).

Genome analysis of the monoclonal marbled crayfish reveals genetic separation over a short evolutionary timescale.

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.

DNA Taxonomy Confirms the Identity of the Widely-Disjunct Mediterranean and Atlantic Populations of the Tufted Ghost Crab Ocypode cursor (Crustacea: Decapoda: Ocypodidae).

The distribution area of the tufted ghost crab Ocypode cursor includes two widely separate sub-areas, i.e. the tropical and subtropical Atlantic coasts of Africa and Macaronesia, and the central-eastern Mediterranean basin. The current disjunct distribution of the species is possibly the remnant of a previous wider and continuous distribution area that was fragmented during the Pleistocene, with the disappearance of the species from the temperate Atlantic Ocean and the western Mediterranean basin, and its survival in the warmer areas of the eastern Atlantic and the Mediterranean Sea. Such disjunction is thus compatible with an ancient isolation between the Mediterranean and Atlantic populations of the species, which could in fact constitute two well-characterized independent evolutionary lineages, or even two cryptic species. Unexpectedly, the sequencing of a fragment of the mtDNA COI gene from Mediterranean and Atlantic Ocypode cursor allopatric populations showed the cohesion of the species throughout its distribution range, and the nesting of Mediterranean populations within the single Atlantic population studied. This pattern is hereby tentatively ascribed to an incomplete lineage sorting due to the large population sizes of both the Atlantic and Mediterranean subpopulations of the species. The current westward expansion of the species in the Mediterranean Sea originating from the Levantine basin, due to ongoing regional sea warming, follows a typical phalanx dispersal mode.

Evolutionary history of the Maltese wall lizard Podarcis filfolensis: insights on the 'Expansion­Contraction' model of Pleistocene biogeography.

The expansion­contraction (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.