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Oxidase Subunit I Gene (oxidase + subunit_i_gene)
Selected AbstractsMolecular phylogeny and phylogeography of flightless beetles Parechthistatus gibber and Hayashiechthistatus inexpectus (Coleoptera: Cerambycidae) inferred from mitochondrial COI gene sequencesENTOMOLOGICAL SCIENCE, Issue 2 2008Hiroshi NAKAMINE Abstract To elucidate the speciation patterns of two endemic flightless cerambycid beetles, Parechthistatus gibber and Hayashiechthistatus inexpectus, molecular phylogenetic analysis was carried out. A 1144 bp region of the cytochrome oxidase subunit I gene was sequenced for individuals from 51 local populations of these species. There were nine haplotype lineages of P. gibber, and H. inexpectus was included within a P. gibber lineage. These lineages were highly divergent and occurred in different regions. Based on previously published molecular change rates for the COI gene (1.5,2.3% per million years), the time of divergence of P. gibber COI haplotypes was inferred to be 3.0,4.6 million years ago, in the Pliocene. [source] Phylogeny and phylogeography of the Lozekia,Kovacsia species group (Gastropoda: Hygromiidae)JOURNAL OF ZOOLOGICAL SYSTEMATICS AND EVOLUTIONARY RESEARCH, Issue 4 2009Zoltán Fehér Abstract The Lozekia,Kovacsia species group comprises three species of high conservation concern, Lozekia transsilvanica (Westerlund, 1876), Lozekia deubeli (M. Kimakowicz, 1890) and Kovacsia kovacsi (Varga and L. Pintér, 1972), which occupy relatively small ranges in the Carpathian-Pannonian region. Despite their conservation concern, the phylogeny and biogeographical history of these species have not been studied by molecular methods up to now. This study, based on mitochondrial cytochrome oxidase subunit I gene sequences, has two main objectives: (i) to infer the phylogenetic relationships within the group in order to test the latest morphology-based system, proposed by Nordsieck [1993, Das System der paläarktischen Hygromiidae (Gastropoda: Stylommatophora: Helicoidea). Arch Molluskenkunde 122:1] and (ii) to reconstruct the distribution history of the three species. The monophyly and thus the systematic distinctness of the three species was confirmed, but our findings do not support the monophyly of the Lozekia genus and therefore contradict the current system of the species group. Genetic diversity was found to be much higher within L. deubeli than within the other two species, a possible explanation of this phenomenon is that L. transsilvanica and K. kovacsi are more recently evolved, younger species. Nested clade phylogeographycal analysis showed that the three species evolved by fragmentation events; probably L. deubeli and the ancestor of the other two species split first. At the intraspecific level, fragmentation events, as well as range expansion, played a significant role in the biogeographical history of this species group. As our findings are based on a single mitochondrial gene, we feel premature to propose changes in the generally accepted system and nomenclature. Further molecular phylogenetic analyses, also involving nuclear DNA sequences, should clarify if the evolutionary scenario suggested by our data is valid, and the three species can indeed be placed within the same genus, Lozekia. Zusammenfassung Die Lozekia,Kovacsia Artengruppe umfasst drei endemische Arten, Lozekia transsilvanica (Westerlund, 1876), Lozekia deubeli (M. Kimakowicz, 1890) und Kovacsia kovacsi (Varga and L. Pintér, 1972), die relativ kleine Verbreitungsgebiete in der karpatisch-pannonischen Region besitzen. Trotz ihrer naturschutzfachlichen Bedeutung wurde die Phylogenie ind biogeographische Historie dieser Arten bisher nicht mit molekularen Methoden untersucht. In dieser Studie werden, basierend auf mitochondrialen COI-Sequenzen, zwei Hauptziele verfolgt: (i) Ermittlung der phylogenetischen Beziehungen in der Gruppe um das aktuelle morphologie.basierte System von Nordsieck (1993) zu testen, und (ii) Rekonstruktion der Verbreitungsgeschichte der drei Arten. In Übereinstimmung mit morphologischen Merkmalsausprägungen wurde die Monophylie und somit die systematische Eigenständigkeit der drei Arten bestätigt, im Gegensatz zur Monophylie der Gattung Lozekia. Die genetische Diversität in L. deubeli war viel höher als in den anderen beiden Arten. Eine mögliche Erklärung dieses Befundes ist, dass L. transsilvanica und K. kovacsi rezenter evolvierte, junge Arten sind. Eine Nested clade phylogeographical analysis (NCPA) zeigte, dass die drei Arten durch Fragmentierungsereignisse entstanden, wahrscheinlich teilten sich L. deubeli und der Vorläufer der anderen beiden Arten zuerst. Auf dem intraspezifischen Niveau spielten Fragmentierungsereignisse und ebenso Arealausdehnungen eine signifikante Rolle in der biogeographischen Geschichte der Artengruppe. Da unsere Ergebnisse auf einem einzigen mitochondrialen Gen basieren, ist es zu früh für Veränderungen am generell akzeptierten System und der Nomenklatur. Weitere molekular-phylogenetische Analysen, die auch nukleäre DNA sequenzen involvieren, müssen das auf unseren Daten basierende evolutionäre Szenario bestätigen und die Fragen klären, ob die drei Arten tatsächlich zur gleichen Gattung, Lozekia, gehören. [source] Contrasting mtDNA diversity and population structure in a direct-developing marine gastropod and its trematode parasitesMOLECULAR ECOLOGY, Issue 22 2009DEVON B. KEENEY Abstract The comparative genetic structure of hosts and their parasites has important implications for their coevolution, but has been investigated in relatively few systems. In this study, we analysed the genetic structure and diversity of the New Zealand intertidal snail Zeacumantus subcarinatus (n = 330) and two of its trematode parasites, Maritrema novaezealandensis (n = 269) and Philophthalmus sp. (n = 246), using cytochrome c oxidase subunit I gene (COI) sequences. Snails and trematodes were examined from 11 collection sites representing three regions on the South Island of New Zealand. Zeacumantus subcarinatus displayed low genetic diversity per geographic locality, strong genetic structure following an isolation by distance pattern, and low migration rates at the scale of the study. In contrast, M. novaezealandensis possessed high genetic diversity, genetic homogeneity among collection sites and high migration rates. Genetic diversity and migration rates were typically lower for Philophthalmus sp. compared to M. novaezealandensis and it displayed weak to moderate genetic structure. The observed patterns likely result from the limited dispersal ability of the direct developing snail and the utilization of bird definitive hosts by the trematodes. In addition, snails may occasionally experience long-distance dispersal. Discrepancies between trematode species may result from differences in their effective population sizes and/or life history traits. [source] Mitochondrial DNA reveals multiple Northern Hemisphere introductions of Caprella mutica (Crustacea, Amphipoda)MOLECULAR ECOLOGY, Issue 5 2008GAIL V. ASHTON Abstract Caprella mutica (Crustacea, Amphipoda) has been widely introduced to non-native regions in the last 40 years. Its native habitat is sub-boreal northeast Asia, but in the Northern Hemisphere, it is now found on both coasts of North America, and North Atlantic coastlines of Europe. Direct sequencing of mitochondrial DNA (cytochrome c oxidase subunit I gene) was used to compare genetic variation in native and non-native populations of C. mutica. These data were used to investigate the invasion history of C. mutica and to test potential source populations in Japan. High diversity (31 haplotypes from 49 individuals), but no phylogeographical structure, was identified in four populations in the putative native range. In contrast, non-native populations showed reduced genetic diversity (7 haplotypes from 249 individuals) and informative phylogeographical structure. Grouping of C. mutica populations into native, east Pacific, and Atlantic groups explained the most among-region variation (59%). This indicates independent introduction pathways for C. mutica to the Pacific and Atlantic coasts of North America. Two dominant haplotypes were identified in eastern and western Atlantic coastal populations, indicating several dispersal routes within the Atlantic. The analysis indicated that several introductions from multiple sources were likely to be responsible for the observed global distribution of C. mutica, but the pathways were least well defined among the Atlantic populations. The four sampled populations of C. mutica in Japan could not be identified as the direct source of the non-native populations examined in this study. The high diversity within the Japan populations indicates that the native range needs to be assessed at a far greater scale, both within and among populations, to accurately assess the source of the global spread of C. mutica. [source] | ||||||||||