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The false blister beetle tribe Stenostomatini includes only the genus Stenostoma , with four species showing an intriguing distribution: Stenostoma lowei (Madeira), Stenostoma cossyrense (Pantelleria), Stenostoma melitense (Malta and southern Sicily) and Stenostoma rostratum, widely distributed along the Mediterranean and North Atlantic coasts. The evolutionary history leading to this distribution has not been investigated. Here, we explore the phylogeny and evolutionary history of the tribe, adopting an integrative approach that combines morphological and molecular data (mitochondrial COI and nuclear CAD and 28S). Moreover, we propose a new key for species identification and update the knowledge on adult and larval ecology. Finally, we propose the following explanation for the current distribution of the species. The genus originated in the Miocene, with S. lowei belonging to the oldest lineage. The remaining species share a common ancestor, dating to the Messinian Salinity Crisis. Stenostoma melitense and S. cossyrense are well differentiated according to morphology, but not according to molecular analysis. The wide distribution of S. rostratum might be related to its strategy of laying eggs within beached driftwood, where larvae develop, easily transported by the currents. Given that neither morphological nor molecular differentiation was detected between the two subspecies of S. rostratum , we propose the new synonymy Stenostoma rostratum septentrionale Švihla, 2005  =  Stenostoma rostratum (Fabricius, 1787) syn. nov. [ABSTRACT FROM AUTHOR]

The Italian geographic region is characterized by complex and diversified biogeographic patterns and is represented by a high number of endemic species. Endemic species characterized by a limited distribution range should be a primary concern in conservation. This article aimed to investigate the phylogenetic and biogeographic relationships of 2 Italian endemic species of the wingless blister beetle genus Meloe Linnaeus, 1758: Meloe (Eurymeloe) apenninicus and Meloe (E.) baudii. Our inferences, based on morphological characters, 2 mitochondrial (16S and COI) and 2 nuclear (CAD and 28S) markers and the use of 3 species delimitation analyses approaches, pointed out the presence of a new Italian endemic species (M. (E.) digiuliorum sp. n.), here described, and 3 different patterns of phylogenetic and biogeographic affinities. M. digiuliorum is close to the Spanish endemic M. orobates comb. n. , revealing a possible fragmentation of the ancestor range in the Pleistocene (ca. 0.84 Mya) followed by isolation in Italy and Spain. M. apenninicus is the sister species of the European-Anatolian M. rugous and M. cfr. rugosus , and this pattern originated around the Plio-Pleistocene boundary (ca. 2.83 Mya) likely influenced by the climatic fluctuations and the presence of the Alpine barrier. Finally, 2 subspecies were referred to M. baudii : the nominal one, endemic to Italy, and the Turanian-E European M. b. glazunovi stat. n. , disclosing a third more recent (ca. 0.64 Mya) pattern of biogeographic disjunction. [ABSTRACT FROM AUTHOR]

Many continental species distributed in the Eurasian steppe occur as relict populations in the mountains of Western Europe. Their biogeographical responses to Quaternary climate changes have been poorly studied; however, they could have responded as cold-adapted species. We investigated the biogeographic history of a steppe beetle, Hycleus polymorphus , using mitochondrial and nuclear DNA sequences (COI , CAD , ITS2), and species distribution modelling (SDM) under present and past bioclimatic envelopes. We first performed a phylogenetic assessment to define species boundaries within the H. polymorphus species group. Specimens previously treated as Hycleus humerosus on morphological grounds are assigned to H. polymorphus , and those identified as Hycleus zebraeus assigned to Hycleus atratus. ITS2 data analyses revealed a strong phylogeographical structure of H. polymorphus populations, with four haplogroups corresponding to the (i) Italian Alps, (ii) French Alps and Pyrenees, (iii) South Balkan and Pontic mountains, and (iv) North Dinaric Alps. Based on these analyses and the SDM, we propose that during a glacial period, following the spread of steppic habitat, H. polymorphus underwent a range expansion from Asia to South-West Europe. Within the Mediterranean area, during the last interglacial the climatic suitability for the species was limited to mountains that acted as refugia and prompted allopatric divergence into four main lineages. [ABSTRACT FROM AUTHOR]

Three non-phoretic blister-beetle species (Mylabris schreibersi, Actenodia distincta and Cabalia segetum) were investigated to trace their Siculo-Maghrebian biogeographic origins and to understand how Tertiary and Quaternary paleogeographic events (e.g. the 'Messinian Salinity Crisis' and the cyclic Quaternary glacio-eustatic marine oscillations) shaped their phylogeographic patterns. Data from CAD and RpP01 nuclear genes highlighted a clear lineage sorting between Sicilian and Maghrebian populations of M. schreibersi, explainable by a vicariance event likely occurred after the 'Messinian Salinity Crisis'. A less marked – but still noticeable – genetic distinction among Sicilian and Maghrebian populations of A. distincta and C. segetum was observed, which could be more referable to moderately old (during Pliocene or late Quaternary) dispersal events. In addition, the low genetic variability and lack of population structure found in Sicily for the three blister-beetle species suggest some drastic reduction in size of Sicilian populations during Pleistocene glacial phases. In general, our results on Meloidae beetles are consistent with published literature, indicating that vicariance or dispersal scenarios can be both plausible explanations of the Siculo-Maghrebian distribution currently observed in a number of animal and plant species. [ABSTRACT FROM AUTHOR]

• Detected 4 main lineages originated in the Miocene in the African continent. • Saharo-Sindian lineages evolved separately from Palaearctic and Afrotropical Region. • Oriental Region: colonized after dispersal event from the Afrotropical Region. • The genus Hycleus includes also the genera Ceroctis and Paractenodia. • No subgeneric division was found, but some phenetic groups resulted well supported. Hycleus is a hyper-diverse genus of blister beetles including ~500 species widely distributed in the Old World, currently divided into three "sections" and into 45 "phenetic" species groups according to morphological characters. Recently the monophyly of Hycleus was questioned pointing out its paraphyly with respect to the genera Ceroctis and Paractenodia. In this study, we built a time-calibrated phylogenetic tree based on DNA sequence data from mitochondrial and nuclear genes obtained from 125 species, to understand the phylogenetic relationships among the species of this genus, to infer the biogeographic processes behind their diversification, and to assess their taxonomy and classification. Our results identified four main lineages one of which included the species belonging to Ceroctis and Paractenodia ; therefore, both taxa are now referred to Hycleus as new synonyms. The three described sections of Hycleus resulted polyphyletic and are rejected, whereas several species groups represented well supported clades. Hycleus likely originated in Africa during the Early Miocene (~20 Mya), and subsequently spread in Europe and western Asia. Later, in the Late Miocene (~6 Mya) a Saharo-Sindian group branched off from the Palaearctic lineage, whereas the Oriental Region was colonized following a dispersal event through the Arabian Peninsula from the Afrotropical Region (~5 Mya). [ABSTRACT FROM AUTHOR]