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Aim  This study uses molecular data in conjunction with palaeogeography to infer the most plausible biogeographical scenario accounting for the current distributional pattern of Iurus dufoureius .
Location  North-eastern Mediterranean region.
Methods  Sequencing of a 441-bp segment of the mitochondrial 16S rRNA gene in seven populations covering the whole distributional range of the species. Phylogenetic analyses performed included neighbour joining, maximum parsimony and Bayesian inference.
Results  The molecular phylogeny showed that two Iurus clades are strongly supported. These clades correspond to the two subspecies Iurus dufoureius dufoureius and Iurus dufoureius asiaticus , currently recognized within the genus. The assumption of a clock-like evolution could not be rejected, and this enabled us to estimate an approximation of the local rate of evolution for the I. dufoureius lineages. Based on the estimated evolutionary rate (0.79 ± 0.17 Myr−1), the split between the two Iurus clades occurred c. 8 Ma.
Main conclusions  Contrary to what was believed in the past, the genus Iurus is an old north-eastern Mediterranean genus that has been differentiating in southern Greece and south-west Turkey at least from the middle Miocene. According to the phylogenetic trees obtained and the dating of the divergence times of lineages, the genus dispersed into the Aegean Archipelago when the Aegean was still a uniform land mass. Although the phylogenetic relationships of I. d. dufoureius populations have been shaped by the most recent vicariant events, the phylogenetic relationships of I. d. asiaticus populations are mostly attributable to older palaeoevents occurring in the area.  相似文献   

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The species Rhoptrocentrus piceus Marshall (Hymenoptera: Braconidae) was reared from the larvae of the xylophagous beetle Psacothea hilaris hilaris (Pascoe) (Coleoptera: Cerambycidae), an exotic pest of Ficus and Morus species native to eastern Asia. It was recorded in the north of Italy in September 2005. This discovery is the first report of this species as parasitoids of the yellow spotted longicorn beetle all over the world.  相似文献   

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Female imagines, subimagines, eggs and larvae of Electrogena antalyensis (Kazanci & Braasch) from Turkey are described for the first time. The results of a thorough analysis of larvae, based on the standard set of diagnostic characters for the identification of Electrogena species, are reported. The peculiarity of several characters places E. antalyensis in an isolated position within the genus Electrogena.  相似文献   

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Oecetis tripunctata is a widely distributed leptocerid in Europe, ranging from the Iberian and Apennine peninsulas and the Central and Western European highlands to the plains of Eastern Europe. The long, single-bladed mandibles are indicative for a predacious lifestyle. This paper describes the previously unknown larva of Oecetis tripunctata. Information on the morphology of the 5th larval instar is given, and the most important diagnostic features are illustrated. A synoptic key for the European species of Oecetis is also provided. In the context of existing identification keys the larva of Oecetis tripunctata keys together with Oecetis intima and Oecetis notata. Oecetis tripunctata is separated from the other two species by the fact that a double row of long setal fringes is lacking at the hind tibiae and that several long setae are present on the protrochantinus.  相似文献   

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The thermally induced helix-coil transitions of three A-T DNAs, d(A)n·d(T)n, d(A-T)n·d(A-T)n, and d(A-A-T)n·d(A-T-T)n, were studied. Experimental transition curves of the DNAs were analyzed using the loop entropy model of DNA melting. The calculation of the melting curve of d(A-A-T)n·d(A-T-T)n is presented using the integral equation formalism of Goel and Montroll. The aim of this work was to evaluate thermodynamic parameters which govern DNA stability and to test the theoretical model employed in the analysis. Our results show (1) an excellent over-all agreement between theory and experiment, (2) a loop entropy exponent k = 1.55 ± 0.05 provided the best fit to all the polymer transition curves, (3) the evaluated stacking free energies reflect the relative stability of the DNAs, and (4) the stacking energies of the ApA·TpT dimer evaluated from d(A)n·d(T)n and d(A-A-T)n·d(A-T-T)n differ. The last result is consistent with different conformations for the dimer in these two polymers.  相似文献   

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The Lacinipolia vicina (Grote) species complex, previously consisting of Lacinipolia vicina, Lacinipolia teligera (Morrison), Lacinipolia pensilis (Grote), and Lacinipolia subalba Mustelin is revised to six species: Lacinipolia vicina (eastern USA), Lacinipolia teligera (southern Great Plains), Lacinipolia pensilis (Pacific Northwest and northern Rocky Mountains), Lacinipolia acutipennis (Grote), stat. rev. (= Lacinipolia subalba syn. n.) (western North America), Lacinipolia sareta (Smith), stat. rev. (Canada and western USA) and Lacinipolia dimocki, sp. n. (California and Pacific Northwest). Lectotypes are designated for Lacinipolia vicina, Lacinipolia teligera and Lacinipolia pensilis.  相似文献   

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The “Megalosaur” remains from Saint-Agnant (Charente-Maritime, France), reported as early as 1881 by Boissellier, are here described and figured for the first time. These bones, as well as a few additional specimens from the nearby locality of Soubise, belong in fact to an indeterminate sauropod. The stratigraphical position of these remains unambiguously indicates an infra-Cenomanian age. However, the presence in this area of continental deposits with Purbeckian and Wealden facies does not allow to decide between an earliest or late Early Cretaceous age.  相似文献   

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The insect orders Megaloptera and Neuroptera are closely related members of the superorder Neuropterida, a relict lineage of holometabolous insects that also includes the Raphidoptera. Megaloptera, composed of the families Sialidae and Corydalidae (including subfamilies Chauliodinae and Corydalinae), has fully aquatic larvae that occur in a wide variety of lotic and lentic habitats, including temporary streams. In total, 2 of 17 families of Neuroptera have aquatic larvae: Nevrorthidae live in the benthos of fast-flowing streams and Sisyridae reside on freshwater sponges. A third family of Neuroptera, Osmylidae, contains some water-dependent species that reside under leaves and rocks along the margins of waterbodies. We recognize 328 extant, described species of Megaloptera (composed of 116 species of Chauliodinae, 131 species of Corydalinae, and 81 species of Sialidae) and 73 species of aquatic Neuroptera (composed of 12 species of Nevrorthidae and 61 species of Sisyridae). Additionally, we estimate that 45 species of Osmylidae are water-dependent, although the ecology of this group is poorly understood. Chauliodinae and Corydalidae are both found in the New World, the Oriental region, and South Africa, but are absent from Europe, the Middle East, Central Asia, tropical Africa, and boreal regions. Chauliodinae is quite speciose in Australia, whereas Corydalinae is absent. Sialidae is most speciose in temperate regions, and is absent from tropical Africa and portions of the Oriental region. Sisyridae and Osmylidae are nearly cosmopolitan, but the relict family Nevrorthidae is limited to Japan, the Mediterranean, and Australia. The discovery of many new species in recent years, particularly among Corydalidae in the Neotropics and China, suggests that our knowledge of aquatic neuropterid diversity is far from complete. Guest editors: E. V. Balian, C. Lévêque, H. Segers and K. Martens Freshwater Animal Diversity Assessment  相似文献   

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The reaction between cimetidine in a methanolic solution of KOH and a dichloromethane solution of PPh3AuCl affords a new compound with formula [L-Au-PPh3] (I) (L = 2-(N-methyl-N′-cyano-N″-ethylguanidino)thiolate), the thiolato ligand resulting from cleavage of one of the thioether bonds of cimetidine. (I) has been characterized by elemental analysis, infrared, and 1H and 13C NMR spectroscopy. Single crystal x-ray structure determination shows that the gold atom is linearly coordinated by a phosphine ligand (Au-P 2.258(1) Å) and by an S atom (Au-S 2.282(1) Å) of the thiolato ligand. Crystal data: triclinic, space group P with a = 8.848(1), b = 11.343(3), c = 12.107(3)Å, = 87.63(1), β = 85.24(1), γ = 79.89(1)°, R = 0.024 for 3673 reflections with I > 3 δ (I).  相似文献   

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