Abstract A new classification of Sitonini Gistel into ten genera is proposed, derived from a phylogenetic analysis based on morphology. Two subgenera of Sitona, Charagmus and Coelositona, are promoted to genus level. Sitona is restricted to the former nominotypical subgenus and redefined using apomorphies, and several species previously included in it are transferred to the genus Coelositona González. The species composition of the genus Charagmus Schönherr is unchanged. Andrion gen.n. is described (type species: Curculio regensteinensis Herbst, 1794). Catachaenus Schönherr, 1840 is synonymized with Eugnathus Schönherr, 1834 ( syn.n. ). Homalorhinus lutosus Hochhuth, 1847 is removed from Sitonini. The relationships represented by the new classification correspond with the evolution of Fabaceae (Leguminosae), mostly with the group of ‘temperate herbaceous tribes’ or Hologalegina. This group is divided into the sister clades, Loteae s.l. and IRLC (inverted repeat‐lacking clade) – a clade well defined by the loss of a structural mutation in the genome of the chloroplast. Andrion does not feed on Hologalegina. Charagmus and Coelositona feed on species of Loteae s.l., whereas members of the genus Sitona feed on species in IRLC. This ability to feed on IRLC plants seems to have been a key trait that enabled the radiation of Sitona into more than 100 species. A key to the genera of Sitonini and illustrations of important morphological features are provided. A new structure is described from the internal sac, the ‘hamuli’. The variability of hamuli between the species of Sitonini is an important new tool in the taxonomy of this tribe. New combinations: Eugnathus circulus (Eydoux & Souleyet, 1839), E. mangarinicus ( Voss, 1925 ), E. scintillans (Pascoe, 1874), E. sulcifrons ( Heller, 1934 ), Charagmus gressorius (Fabricius, 1792), Ch. intermedius Küster, 1847, Ch. griseus (Fabricius, 1775), Ch. cachectus Gyllenhal, 1834, Ch. stierlini Reitter, 1903 , Ch. variegatus (Fåhraeus, 1840), Coelositona ribesi ( González, 1971 ), C. cambricus (Stephens, 1831), C. cinerascens (Fåhraeus, 1840), C. limosus (Rossi, 1792), C. ocellatus (Küster, 1849), C. latipennis (Gyllenhal, 1834), C. puberulus ( Reitter, 1903 ), C. villosus (Allard, 1869), Andrion regensteinense (Herbst, 1794) and Anemeroides lutosus (Hochhuth, 1847). 相似文献
We used transmission electron microscopy to compare the cytopathology induced in plants by five criniviruses (genus Crinivirus; Lettuce infectious yellows virus (LIYV), Cucurbit yellow stunting disorder virus (CYSDV), Tomato infectious chlorosis virus (TICV), Tomato chlorosis virus (ToCV) and Beet pseudo‐yellows virus (BPYV) (Hartono et al., 2003)). We also compared the patterns of infection for plants and mesophyll protoplasts infected by LIYV and Beet yellows virus (BYV), type members of genera Crinivirus and Closterovirus, respectively. The main cytopathological effects induced in plants by criniviruses were common in young leaves and included alterations of the chloroplasts and the presence of BYV‐type inclusion bodies in companion cells. Virus‐like particles were present in sieve tubes and vascular parenchyma cells as scattered particles, or in companion cells as large masses forming cross‐banded inclusions. Depending on the virus and the plant, it was possible to find virions or virus‐like particles out of the phloem cells, but only in cells of the bundle sheath. Virion‐like particles were never found outside of the vascular tissue. Accumulation of electron‐dense material at the plasmalemma was common for criniviruses, but only LIYV infections produced characteristic conical electron‐dense plasmalemma deposits (PDs). The LIYV‐induced PDs have a crystalline‐like structure and were found at the internal side of plasmalemma. 相似文献
A molecular phylogeny was reconstructed for 26 recognized genera of the Gymnophthalmidae using a total of 2379 bp of mitochondrial (12S, 16S and ND4) and nuclear (18S and c-mos) DNA sequences. We performed maximum parsimony (MP) and maximum likelihood (ML) analyses, and data partitions were analysed separately and in combination under MP. ML analyses were carried out only on the combined sequences for computational simplicity. Robustness for the recovered nodes was assessed with bootstrap and partitioned Bremer support (PBS) analyses. The total molecular evidence provided a better-resolved hypothesis than did separate analysis of individual partitions, and the PBS analysis indicates congruence among independent partitions for support of some internal nodes. Based on this hypothesis, a new classification for the family is proposed. Alopoglossus , the sister group of all the other Gymnophthalmidae was allocated to a new subfamily Alopoglossinae, and Rhachisaurus (a new genus for Anotosaura brachylepis) to the new Rhachisaurinae. Two tribes are recognized within the subfamily Gymnophthalminae: Heterodactylini and Gymnophthalmini, and two others within Cercosaurinae (Ecpleopini and Cercosaurini). Some ecological and evolutionary implications of the phylogenetic hypothesis are considered, including the independent occurrence of limb reduction, body elongation, and other characters associated with fossoriality. 相似文献
The soils of the Pampas are thought to be generally non-contaminated but there is growing evidence of trace element accumulation at some specific sites. The goal of this study was to measure the current levels of the main Potentially Toxic Elements (PTE) in the top horizon and in specific soil profiles so that we would establish the baseline concentrations of these elements. Eighty-eight top soils and three soil profiles were sampled. The samples were acid digested. Arsenic, boron, barium, cadmium, cobalt, chromium, copper, lead, manganese, mercury, molybdenum, nickel, silver, selenium and zinc were determined with inductively coupled argon plasma emission spectrometry (ICPES).
All of the values found are within the normal range for uncontaminated soils as reported from several continents. Elements with high environmental risk potential are lower than the admissible range of the European Union and some of them are orders of magnitude lower than those of the United States Environmental Protection Agency (US-EPA) 501 levels. Potentially Toxic Elements contents increased with depth or showed a maximum concentration at the B2 horizon. This is related to the parent material and the pedogenetic processes but not to recent contamination. Soil profiles showed higher concentrations of PTE in clayey horizons. However, these relationships did not appear in top soil samples in any soil Great Group studied. The shown data establishes a baseline for PTE concentrations for Pampas soils. 相似文献
ABSTRACT. The mixotrophic dinoflagellate Paragymnodinium shiwhaense n. gen., n. sp. is described from living cells and from cells prepared by light, scanning electron, and transmission electron microscopy. In addition, sequences of the small subunit (SSU) and large subunit (LSU) rDNA and photosynthetic pigments are reported. The episome is conical, while the hyposome is hemispherical. Cells are covered with polygonal amphiesmal vesicles arranged in 16 rows and containing a very thin plate‐like component. There is neither an apical groove nor apical line of narrow plates. Instead, there is a sulcal extension‐like furrow. The cingulum is as wide as 0.2–0.3 × cell length and displaced by 0.2–0.3 × cell length. Cell length and width of live cells fed Amphidinium carterae were 8.4–19.3 and 6.1–16.0 μm, respectively. Paragymnodinium shiwhaense does not have a nuclear envelope chamber nor a nuclear fibrous connective (NFC). Cells contain chloroplasts, nematocysts, trichocysts, and peduncle, though eyespots, pyrenoids, and pusules are absent. The main accessory pigment is peridinin. The sequence of the SSU rDNA of this dinoflagellate (GenBank AM408889) is 4% different from that of Gymnodinium aureolum, Lepidodinium viride, and Gymnodinium catenatum, the three closest species, while the LSU rDNA was 17–18% different from that of G. catenatum, Lepidodinium chlorophorum, and Gymnodinium nolleri. The phylogenetic trees show that this dinoflagellate belongs within the Gymnodinium sensu stricto clade. However, in contrast to Gymnodinium spp., cells lack nuclear envelope chambers, NFC, and an apical groove. Unlike Polykrikos spp., which have a taeniocyst–nematocyst complex, P. shiwhaense has nematocysts without taeniocysts. In addition, P. shiwhaense does not have ocelloids in contrast to Warnowia spp. and Nematodinium spp. Therefore, based on morphological and molecular analyses, we suggest that this taxon is a new species, also within a new genus. 相似文献