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1.
One of the most promising alternative technologies to antifouling (AF) biocides based on toxic heavy metals lies in the development of natural eco-friendly biocides. The present study evaluates the AF potential of structurally different compounds containing a 3-alkylpyridine moiety. The products, namely poly 3-alkylpyridinium salts, saraine, and haminols, were either extracted or derived from natural sources (the sponges Haliclona sp. and Reniera sarai and the mollusc Haminoea fusari), or obtained by chemical synthesis. All the molecules tested showed generally good anti-settlement activity against larvae of the barnacle Amphibalanus (=Balanus) amphitrite (EC50 values between 0.19 and 3.61?μg?ml?1) and low toxicity (LC50 values ranging from 2.04 to over 100?μg?ml?1) with non-target organisms. For the first time, the AF potential of a synthetic monomeric 3-alkylpyridine was demonstrated, suggesting that chemical synthesis is as a realistic way to produce large amounts of these compounds for future research and development of environmentally-friendly AF biocides.  相似文献   

2.
Based on the high, non-toxic and reversible antifouling activity of the polymeric 3-alkylpyridinium salts isolated from the sponge Reniera sarai, the anti-settlement activity and toxicity of a series of synthetic analogues has been studied. All the test compounds were less efficient than the natural polymers, suggesting that the high and reversible anti-macrofouling activity of the natural polymers could derive from their detergent-like properties. The values obtained for EC50sett. of inhibition of cyprid settlement and EC50imm. as naupliar toxicity for the synthetic compounds indicate that the presence of single or multiple charges in the structure is not relevant for the antifouling activity which, conversely, is favoured by increasing the length of the alkyl chain, or by the presence of uncharged pyridine units. The compound 1,8-di(3-pyridyl)octane was the most efficient (EC50sett.= 0.44?μg?ml–1), although with a higher toxicity on naupliar stage of B. amphitrite than the natural polymers.  相似文献   

3.
Twenty five surface samples/moss cushions were collected for palynological analysis from open areas of Reasi District, Jammu and Kashmir (India). These samples were used to investigate the relationships between extant vegetation and modern pollen spectra, which serve as modern analogue for the reliable ecological interpretation of fossil pollen records. The present vegetation in the region comprises tropical dry deciduous forests and subtropical pine forests with scattered stands of oak. The pollen analysis reveals that Pinus sp. (average 69% in the pollen assemblages), amongst the conifers, dominates the pollen rain, which can be attributed to its high pollen productivity and exceptional pollen dispersal efficiency. Cedrus sp. and Podocarpus sp. pollen contribute with an average of 16 and 5% to the total pollen rain. Other conifers such as Picea sp., Abies sp., Juniperus sp. and Tsuga sp., as well as broad-leaved taxa such as Quercus sp., Alnus sp., Betula sp., Carpinus sp., Corylus sp., Juglans sp., Ulmus sp., Salix sp., Elaeocarpus sp., Mallotus sp. and Aesculus sp., have lower averages of 1 to 4.5% in the total pollen rain which could be either due to their poor pollen dispersal efficiency or to the poor preservation in the samples. Tubuliflorae (average 25%), Poaceae (average 6.26%), Cerealia and other crop plants (average 7.68%) are other prominent taxa in the pollen rain. The nearly complete absence of members of tropical dry deciduous forests in the pollen spectra likely is due to the fact that most species in this vegetation type are not wind pollinated.  相似文献   

4.
The ant subfamilies Ponerinae, Cerapachyinae and Pseudomyrmecinae are revised in the Baltic, Bitterfeld, Rovno, and Scandinavian ambers of the Late Eocene age. Thirteen new species are described: Amblyopone groehni sp. n., A. electrina sp. n., Pachycondyla conservata sp. n., P. tristis sp. n., Ponera lobulifera sp. n., P. mayri sp. n., P. wheeleri sp. n., Gnamptogenys rohdendorfi sp. n., Bradoponera similis sp. n., Proceratium eocenicum sp. n. (Ponerinae), Procerapachys sulcatus sp. n. (Cerapachyinae), Tetraponera europaea sp. n., and T. groehni sp. n. (Pseudomyrmecinae). Tetraponera angustata (Mayr) is synonymized with T. simplex (Mayr). Keys to species are provided.  相似文献   

5.
The delineation of Gammarus species is controversial because of extensive intraspecific morphological variation. The current study examined DNA sequences from the mitochondrial cytochrome c oxidase subunit I and the nuclear 28S genes as well as morphological and ecological data to determine the species boundaries of Gammarus species from China. The results of molecular analyses showed that Gammarus sp1, G. sp2, G. sp3, and G. sp4 are monophyletic and deeply divergent from sister groups. Detailed morphological and ecological comparisons with closely related species were consistent with molecular analyses. Gammarus sp1, G. sp2, G. sp3, and G. sp4 were described as four new species: Gammarus illustris sp. nov. , Gammarus clarus sp. nov. , Gammarus hypolithicus sp. nov. , and Gammarus parvioculus sp. nov. We recommend that molecular detected species should be formally named and described for future research. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 160 , 215–253.  相似文献   

6.
The present paper reports thirty‐three species of the genus Cryptolechia in China. Fifteen species are described as new to science: C. deflecta sp. nov., C. kangxianensis sp. nov., C. microbyrsa sp. nov., C. falsivespertina sp. nov., C. zhengi sp. nov., C. neargometra sp. nov., C. paranthaedeaga sp. nov., C. cornutivalvata sp. nov., C. fascirupta sp. nov., C. stictifascia sp. nov., C. jigongshanica sp. nov., C. mirabilis sp. nov., C. anthaedeaga sp. nov., C. gei sp. nov. and C. varifascirupta sp. nov. The genital structures of the new species are illustrated.  相似文献   

7.
Three new genera and 27 new species of gall midges are described from the Late Eocene ambers: Henria baltica sp. nov., Frirenia manca sp. nov., F. musicata sp. nov., Leptosyna samlandica sp. nov., L. fastosa sp. nov. from Baltic amber and H. xystica sp. nov., H. liquida sp. nov., Stellasegna vlaskini gen. et sp. nov., S. vaporea sp. nov., S. nexa sp. nov., Rasnitsia verticosa gen. et sp. nov., F. rohdendorfi sp. nov., F. schevchenkoi sp. nov., F. melica sp. nov., F. lukashevichae sp. nov., F. leporidis sp. nov., F. marmarygma sp. nov., F. vesana sp. nov., Vincinescia alisae gen. et sp. nov., L. margarita sp. nov., L. munifera sp. nov., L. sukachevae sp. nov., L. assa sp. nov., L. larga sp. nov., L. vegeta sp. nov., L. vaticina sp. nov., and L. shcherbakovi sp. nov. from Rovno amber. Strobliella capitata Fedotova is redescribed as Henria capitata (Fedotova, 2004) (comb. nov.). Diagnoses of Henria (= Electroxylomyia Nel et Prokop, syn. nov.), Frirenia, and Leptosyna are revised. As a result, Henria comprises 3 extant and 5 extinct (Late Eocene) species, including H. eocenica (Nel et Prokop), comb. nov. (= Electroxylomyia eocenica), Frirenia comprises 1 extant and 10 Late Eocene species, and Leptosyna comprises 3 extant and 11 Late Eocene species. The tribe Heteropezini is elevated to the supertribal rank (Heteropezidi) and included in the subfamily Lasiopterinae. Leptosynini is treated as a separate tribe, and Lasiopterinae is considered as part of Cecidomyiidae s. str. (i.e., excluding Lestremiidae). Keys to the tribes and genera of Heteropezidi and to species of Henria, Stellasegna, Frirenia, and Leptosyna are provided. The gall midge faunas of the Rovno and Baltic ambers are compared. Phylogenetic relationships within the supertribe are hypothesized.  相似文献   

8.
The inside of Pinus thunbergii could be a reliable screening source for a useful agent in controlling plant disease. Isolation of endophytic actinomycetes from P. thunbergii and their potential as biocontrol agents against the plant pathogen Cylindrocladium sp. were investigated. Two endophytic actinomycetes, Streptomyces sp. and Microbispora sp., were isolated from surface-sterilised root tissues of P. thunbergii seedlings. The recovery test of these two endophytic actinomycetes from pine seedling showed that Streptomyces sp. was isolated from only roots, but Microbispora sp. was isolated from both roots and leaves. Thus, Microbispora sp. is able to move to leaves from roots. Moreover, we evaluated the potential of both strains as biocontrol agents against Cylindrocladium sp. Two weeks after inoculation of Cylindrocladium sp. alone, pine seedlings showed a 50% mortality rate. Co-inoculation of Cylindrocladium sp. and Microbispora sp. did not affect seedling mortality rate. However, inoculation with both Cylindrocladium sp. and Streptomyces sp. reduced seedling mortality to 12%. Streptomyces sp. could be a useful agent in controlling pine disease caused by Cylindrocladium sp. Thus, it seems that Streptomyces sp. may induce a local host defence reaction and Microbispora sp. systemically spreads to aerial parts through the transpiration stream.  相似文献   

9.
Bioactive 3-alkylpyridinium polymers (poly-APS) have recently been isolated from the marine sponge Reniera sarai. Previous results have shown that these molecules in aqueous solutions form supramolecular aggregates with an average hydrodynamic radius of 23±2 nm. To obtain additional evidences about the shape and the dimensions of poly-APS aggregates, we used atomic force microscopy (AFM) operating in tapping mode. The images clearly showed adsorbed aggregates with a lateral dimension of ≈40 nm and a thickness of the order of ≈1 nm. The distribution of volumes of the adsorbed aggregates is very similar to the distribution of hydrodynamic radii as obtained from the dynamic light scattering experiments. The volume distribution of these aggregates shows a maximum at 1750 nm3, which corresponds to a sphere with a radius of 7.5 nm.  相似文献   

10.
The sugar and osmophilic fungal composition of soils amended with five organic substrates (newspaper, orange peel, bromegrass leaves, wheat straw and wood sawdust) was estimated after 2, 4, 6, 8 and 10 weeks using the dilution plate method on glucose and 50% sucrose Czapek's agar media. Wheat straw was the best substrate for total counts of both sugar and osmophilic fungi followed by newspaper, bromegrass leaves, wood sawdust and orange peel. Wood sawdust supported the highest average counts of total sugar fungi, Fusarium, Mucor, Scopulariopsis, Trichoderma and Trimmatostroma spp.; Newspaper, of Aspergillus (8 spp.), Penicillium (4 spp.) and Chaetomium sp. bromegrass leaves of Cladosporium sp., Humicola sp. and Sporotrichum sp.; orange peel, ofAlternaria sp., Circinella sp. and Stachybotrys sp.; and wheat straw, of Botryotrichum sp. and Myrothecium sp. Bromegrass leaves and orange peel supported the highest average counts of total osmophilic fungi, Aspergillus (10 spp.), Cladosporium sp. Paecillomyces sp. and Rhizopus sp.; and of Stemphylium sp., Trichoderma sp., Humicola sp. and Circinella sp. respectively; wheat straw, of Epicoccum sp., Scopulariopsis sp. and Trichothecium sp.; newspaper, of Penicillium (4 spp.) and Alternaria sp.; and wood sawdust of Curvularia sp. and Fusarium (3 spp.). The best colonizers throughout the experimental periods were Aspergilus and Penicillium spp.  相似文献   

11.
A survey was conducted to determine the nematodes associated with the soil, substratum and roots of the ornamental plant, Pseuderanthemum atropurpureum, grown in the Aligarh district of western Uttar Pradesh, India. Ten genera of plant parasitic nematodes, viz. Meloidogyne spp., Helicotylenchus sp., Hemicriconemoides sp., Hoplolaimus sp., Xiphinema sp., Pratylenchus sp., Trichodorus sp., Tylenchorhynchus sp., Aphelenchoides sp. and Rotylenchus sp., were isolated from 345 soil samples collected from 15 different localities. Our study indicates that among the 10 genera of the plant parasitic nematodes, Meloidogyne spp. was widely spread in all the examined localities of Aligarh district, except at Khair. It was observed that the population density and diversity of nematodes in all the soil samples was not uniform. Meloidogyne spp. showed the highest absolute frequency and relative frequency followed by Helicotylenchus sp., Hemicriconemoides sp., Xiphinema sp., Hoplolaimus sp., Pratylenchus sp., Trichodorus sp., Tylenchorhynchus sp., Aphelenchoides sp. and Rotylenchus sp. Since no records are available in the literature related to the association of root-knot nematode in P. atropurpureum, it is worthy to note that this study may be considered as a new hope towards further study of the interaction between the root-knot nematode and ornamental plant P. atropurpureum if any.  相似文献   

12.
Abstract: A rich, diverse Permian ostracod fauna has been recovered from the red and grey, laminated shales and quartz‐rich shales of the Triassic Lercara Formation. Forty‐seven species have been identified, 13 of which are newly described here; they belong to 26 genera of which three are new: Anahuacia lercaraensis sp. nov., Aurigerites siciliaensis sp. nov., Bairdia portellaensis sp. nov., Cristanaria? katyae sp. nov., Fabalicypris gruendeli sp. nov., Lethiersa salomonensis gen. et sp. nov., Lethiersia sinusoventralis gen. et sp. nov., Portella trapezoida gen. et sp. nov., Siciliella elongata gen. et sp. nov., Siciliella infernespinosa gen. et sp. nov., Siciliella prima gen. et sp. nov., Siciliella quadrata gen. et sp. nov., and Siciliella spinorobusta gen. et sp. nov. The assemblages contain or are composed of palaeopsychrospheric forms, which are regarded as index fossils for deep environments. The bathymetry of the different associations in life is evaluated.  相似文献   

13.
Abstract

Seven new species of nematode are described from the hind-gut of several different millipedes indigenous to New Zealand: Heth hamatus n. sp. from Spirobollelus antipodarus and Icosidemus hochstetteri from Auckland, Erythrodemus echinopogon from Seddonville, and Eumasligonus sp. from Aickens, and Avenue Scenic Reserve; Thelastoma moko n. sp. from coastal specimens of Eumastigonus sp.; Thelastoma rigo n. sp. from montane specimens of Eumastigonus sp.; Dudekemia prolifica n. sp. from Spirobellelus antipodarus; Dudekemia alpinensis n. sp. from the montane Eumastigonus sp.; Dudekemia kaorinus n. sp. from Eumastigonus kaorinus from Hardys Creek; and Dudekemia hirsutus n. sp. from Erythrodemus echinopogon from Seddonville.

The family Rhigonematidae is reviewed.  相似文献   

14.
A total of 228 bacteria with an ability to resist toxic heavy metals were isolated from 8 selected sites of the Lagos Lagoon. The bacteria isolated wereStaphylocaccus sp.,Bacillus sp.,Pseudomonas sp.,Streptococcus sp.,Moraxella sp.,Escherichia coli, Proteus sp.,Klebsiella sp. andSalmonella sp. The heavy metals to which resistance was recorded were mercury, lead, zinc, cobalt, copper and chromium. The lagoon sites from which the highest number of resistant bacteria were isolated were Marina and Ebute-Ero. The heavy metal to which most bacteria were resistant was cobalt, while the least was chromium. The significance of the result is discussed in relation to the Nigerian environment and human health.  相似文献   

15.

Epizoans were part of an epifaunal suspension‐feeding paleocommunity of the interchannel mudstone fades of the Borden delta (Edwardsville Formation, Mississippian, Indiana, USA). The paleocommunity was composed predominantly of bryozoans, crinoids, and brachiopods. A total of 26 epizoans and 42 potential hosts were present with Composita globosa, crinoids, and Cladochonus beecheri the principal hosts. Associations are classified as obligate, preferred, random, variable, and limited data. Stenoporid sp. B, Phosphannulus sp., and Platyceras spp. had obligate relationships with crinoids; Cornulitella sp. and Dendrina sp. had obligate relationships with Composita globosa; Ropalonaria sp. had an obligate relationship with Cladochonus beecheri; and Amplexizaphremis? sp. had an obligate relationship with fenestrate bryozoans. The following taxa had preferred associations to more than one host: Ascodictyon sp., Cheilotrypa sp., Corynotrypa sp. A, Corynotrypa sp. B, Fistulipora sp., Heteralosia keokuk, stenoporid sp. A, and fenestrates. Totypammina sp. displayed a nearly random pattern of settlement; and Cladochonus beecheri, Spirorbis sp., Thuramminoides sp., and crinoids have variable associations with hosts between the two localities studied.  相似文献   

16.
Cumaceans (Crustacea: Peracarida) belonging to the family Bodotriidae collected between 206 and 3680 m depth, during the French campaigns BIOCAL and BIOGEOCAL in waters of New Caledonia, KARUBAR in Indonesia and BORDAU 1 around Fiji were studied. The 93 specimens belonging to this family were assigned to 11 species, ten of them new to science, namely Cyclaspis variosculpta sp. nov., Cyclaspis richeri sp. nov., Cyclaspis dictyota sp. nov., Cyclaspis decora sp. nov., Cyclaspis magna sp. nov., Cyclaspoides erugatus sp. nov., Alticuma? ectyphum sp. nov., Apocuma pacificum sp. nov., Hypocuma fragosum sp. nov. and Bathycuma coremium sp. nov. The genera Cyclaspoides and Hypocuma are recorded for the first time from the Pacific Ocean. © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society, 2008, 152 , 227–254.  相似文献   

17.
Coral reefs are renowned as complex ecosystems with an extremely large biodiversity. Parasite-host relationships contribute substantially to this, but are poorly known. We describe the results of a study in which approximately 60,000 corals were searched for parasitic Leptoconchus snails (Gastropoda: Coralliophilidae) in Indo-West Pacific waters of Egypt, the Maldives, Thailand, Palau and Indonesia. We discovered an adaptive radiation of 14 snail species, each of which lives in species-specific association with one or more of 24 mushroom coral species. The 14 snail species are described as new to science under the names Leptoconchus inactiniformis sp. nov., L. inalbechi sp. nov., L. incrassa sp. nov., L. incycloseris sp. nov., L. infungites sp. nov., L. ingrandifungi sp. nov., L. ingranulosa sp. nov., L. inlimax sp. nov., L. inpileus sp. nov., L. inpleuractis sp. nov., L. inscruposa sp. nov., L. inscutaria sp. nov., L. intalpina sp. nov., and L. massini sp. nov. Their separation is based on indisputable molecular differences, whereas the rudimentary shell characters or impoverished anatomical details do not allow identification. The coral hosts also serve to distinguish the snail species, as none of the former was found to contain more than one of the latter. The complexity of coral reefs is still underrated, as is shown here by the application of DNA taxonomy as an indispensable approach to unravel cryptic radiations, which must be known in order to understand the functioning of the ecosystem.  相似文献   

18.
The following nine new species of the genus Nahublattella Bruijning, 1959 are described from Ecuador and Mexico: N. cuyabeno sp. n., N. alexandri sp. n., N. incurvata sp. n., N. maya sp. n., N. plena sp. n., N. bispina sp. n., N. ultima sp. n., N. beikoi sp. n., and N. reticulata sp. n. The structure of the male genitalia of the new species is described in detail. The genus diagnosis is discussed.  相似文献   

19.
Abstract: Bulk sampling of phosphate‐rich horizons within the British Coniacian to Campanian (Upper Cretaceous) yielded very large samples of shark and ray teeth. All of these samples yielded teeth of diverse members of the Carcharhiniformes, which commonly dominate the fauna. The following species are recorded and described: Pseudoscyliorhinus reussi ( Herman, 1977 ) comb. nov., Crassescyliorhinus germanicus ( Herman, 1982 ) gen. nov., Scyliorhinus elongatus ( Davis, 1887 ), Scyliorhinus brumarivulensis sp. nov., ?Palaeoscyllium sp., Prohaploblepharus riegrafi ( Müller, 1989 ) gen. nov., ?Cretascyliorhinus sp., Scyliorhinidae incertae sedis 1, Scyliorhinidae incertae sedis 2, Pteroscyllium hermani sp. nov., Protoscyliorhinus sp., Leptocharias cretaceus sp. nov., Palaeogaleus havreensis Herman, 1977 , Paratriakis subserratus sp. nov., Paratriakis tenuis sp. nov., Paratriakis sp. indet. and ?Loxodon sp. Taxa belonging to the families ?Proscylliidae, Leptochariidae and Carcharhinidae are described from the Cretaceous for the first time. The evolutionary and palaeoecological implications of these newly recognised faunas are discussed.  相似文献   

20.
Three new genera, one new subgenus, and 13 new species (Strogulomorpha separata sp. n., S. davidi sp. n., S. proxima sp. n., Luzarida lata sp. n., Luzara venado sp. n., L. sapani sp. n., Ucayacla pulchella gen. et sp. n., Peruzara atalaya gen. et sp. n., P. loreto sp. n., Amazonacla imitata gen. et sp. n., A. primitiva sp. n., Leptopsis (Leptopsis) ucayali sp. n., and L. (Aberracla subgen. n.) morona sp. n.) are described. The composition of the tribes Paragryllini and Luzarini and of the genera Luzarida Heb. and Luzara Walk is discussed. The new synonymies Luzarida Hebard, 1928 = Ecuazarida Nischk et Otte, 2000, syn. n.; Lerneca Walker, 1869 = Doposia Otte et Perez-Gelabert, 2009, syn. n.; Nemoricantor Desutter-Grandcolas et Hubbell, 1993 = Kumalorina Otte et Perez-Gelabert, 2009, syn. n. are given. The systematic position of some previously described species is corrected.  相似文献   

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