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The bioavailability of glyphosate from plant residues may be high in the soil matrix. In order to determine the impact of litter contaminated with glyphosate (GLY) on the growth and cocoon production of the earthworm Pontoscolex corethrurus as well as on acid and basic phosphatase activities and soil pH, a commercial glyphosate-based herbicide was applied to three types of litter mixed with soil. Earthworms from a GLY -free coffee plantation were grown for 132 days in microcosms in a two-factorial design. The first factor was glyphosate (GLY; 21.6 g of glyphosate per kg of litter, with two levels (− GLY , +GLY ), and the second factor was type of litter ( Coffea arabica , Musa cavendishii, Inga vera ). All studied factors (except days*litter*glyphosate interaction) had significant effects on earthworm biomass ( P < 0.05 ). Treatments with Coffea and Musa litter -GLY had significantly higher biomass ( P < 0.05), whereas treatments with Inga litter -GLY and +GLY had the lowest biomass. A decline in earthworm biomass was detected in all treatments with glyphosate ( +GLY ) after 72 days. No significant effect on cocoon production was detected for the main factors or their interaction. Litter type showed a marginal effect ( P = 0.06 ); the average (± SE) number of cocoons decreased from Musa (5.8 ± 2.9) to Coffea (1.3 ± 0.56) and Inga (0.17 ± 0.17). Soil pH significantly ( P = 0.006) decreased at the end of the experiment from 4.4 ± 0.17 in -GLY to 3.9 ± 0.06 in +GLY . Acid phosphatase activity increased in treatments with Musa and Inga +GLY ( P < 0.05), while alkaline phosphatase activity in the same substrates was higher in treatments with -GLY ( P < 0.05). We conclude that repeated application of litter contaminated with glyphosate negatively affects earthworm vitality and increases soil acidity and acid phosphatase activity. [ABSTRACT FROM AUTHOR]

Abstract: Despite the increasing interest in biological invasions by earthworms which cause important changes in soils, biota and ecosystem processes after introduction, little is known about their history of colonisation. Population genetics tools may provide interesting insights into evolutionary processes occurring during an invasion phase; however a prerequisite is the knowledge of genetic variability within the native range of the species. The aim of this study was to estimate the genetic variation of a tropical peregrine earthworm, Pontoscolex corethrurus, in French Guiana, a region included within its native range. The clonal variability of this parthenogenetic species was assessed using 106 AFLP loci analysed in 113 individuals from five populations from the Nouragues reserve, in the Amazonian primary forest, and one population from the city of Cayenne. We found a higher level of genetic diversity in populations originating from the most disturbed sites, thus suggesting that dispersal events, probably linked to human activities, supplied these populations with migrants. Moreover, patterns of genetic differentiation between populations suggested accidental transfer of P. corethrurus between Cayenne and the Nouragues reserve as well as between populations of the reserve. Altogether, our results highlighted that AFLPs are adequate molecular markers to trace back the history of colonisation by this species. [Copyright &y& Elsevier]

Abstract: To more confidently assess phylogenetic relationships among astome ciliates, we obtained small subunit (SSU) rRNA sequences from nine species distributed in six genera and three families: Almophrya bivacuolata, Eudrilophrya complanata, Metaracoelophrya sp. 1, Metaracoelophrya sp. 2, Metaracoelophrya intermedia, Metaradiophrya sp., Njinella prolifera, Paraclausilocola constricta n. gen., n. sp., and Paraclausilocola elongata n. sp. The two new species in the proposed new clausilocolid genus Paraclausilocola n. gen. are astomes with no attachment apparatus, two files of contractile vacuoles, and an arc-like anterior suture that has differentiations of thigmotactic ciliature on the anterior ends of the left kineties of the upper surface. Phylogenetic analyses were undertaken using neighbor-joining, Bayesian inference, maximum likelihood, and maximum parsimony. The nine species of astomes formed a strongly supported clade, showing the subclass Astomatia to be monophyletic and a weakly supported sister clade to the scuticociliates. There were two strongly supported clades within the astomes. However, genera assigned to the same family were found in different clades, and genera assigned to the same order were found in both clades. Thus, astome taxa appear to be paraphyletic when morphology is used to assign species to genera. [Copyright &y& Elsevier]

Abstract: The giant extracellular hemoglobin of Glossoscolex paulistus (HbGp) has a molecular mass (M) of 3600±100kDa and a standard sedimentation coefficient () of 58S, estimated by analytical ultracentrifugation (AUC). In the present work, further AUC studies were developed for HbGp, at pH 10.0, which favors oligomeric dissociation into lower M species. The HbGp oligomer is formed by globin chains a , b , c and d plus the linker chains. The pure monomeric fraction, subunit d , and HbGp at pH 10.0, in the presence of β-mercaptoethanol, were also studied. Our results indicate that for samples of pure subunit d , besides the monomeric species with of 2.0S, formation of dimer of subunit d is observed with of around 2.9S. For the whole HbGp at pH 10.0 contributions from monomers, trimers and linkers are observed. No contribution from 58S species was observed for the sample of oxy-HbGp at pH 10.0, showing its complete dissociation. For cyanomet-HbGp form a contribution of 17% is observed for the un-dissociated oligomer, consistent with data from other techniques that show the cyanomet-form is more stable as compared to oxy-HbGp. Masses of HbGp subunits, especially trimer abc and monomeric chains a , b , c and d , were also estimated from sedimentation equilibrium data, and are in agreement with the results from MALDI-TOF-MS. [Copyright &y& Elsevier]

Summary: Radopholus similis is a worldwide endoparasitic nematode that greatly hampers banana (Musa acuminata, Cavendish subgroup) productivity. Earthworms are known to closely interact with above-ground and under-ground soil biota and particularly with plants and microfaunal communities. This study was aimed at investigating, under greenhouse conditions, the effects of the earthworm Pontoscolex corethrurus on banana growth and nutrient uptake, and assessing the influences of this earthworm on the development of an inoculated population of R. similis. Six-week-old tissue culture banana plants were submitted to four treatments: with P. corethrurus, R. similis, P. corethrurus+R. similis, and a control with no earthworms or nematodes. At the end of the experiment, the P. corethrurus treatments showed significantly higher leaf surface areas, shoot dry root weights, and root fresh weights than those without earthworms. This root growth enhancement probably contributed to the evident but non-significant decrease in the density of nematodes in the roots, even though earthworms did not reduce the total number of nematodes per whole root system. Moreover, the presence of earthworms slightly alleviated the severity of root damage. N bioavailability in the soil, along with N, Ca, and Mg content of banana plants, were also significantly increased in the presence of earthworms. Our results demonstrated that banana plant growth and nutrition were positively influenced by earthworms. Cropping practices that boost the development of earthworm communities in soil should therefore be promoted to enhance sustainability and to naturally alleviate nematode impact. [Copyright &y& Elsevier]

Abstract: In this work, MALDI-TOF-MS analysis was performed to obtain information on the molecular mass of the different subunits from the giant extracellular hemoglobin of Glossoscolex paulistus (HbGp) in the oxy-form. Experiments were performed for the whole protein at pH 7.0, for the partially dissociated protein at pH 9.0, and for the fraction obtained from gel filtration in Sephadex G-200, at pH 9.0, corresponding to the isolated monomer d. Besides that, experiments were performed for the whole protein treated with 2-mercaptoethanol in order to monitor the effects of reduction of the disulfide bonds, which are expected to maintain the trimer (abc) in the native molecule. The results are compared to those reported for the homologous hemoglobin of Lumbricus terrestris (HbLt) and some tentative assignments are made for the observed polypeptides. The monomer d is found to exist in, at least, two major forms of identical proportions with masses of 16,355±25 and 16,428±24Da, respectively. Two minor forms were also observed around 16kDa for the monomers. Upon disulfide bonds reduction the peak associated to the trimer is absent in the mass spectrum, and new peaks assigned tentatively to the monomers a, b and c on the basis of comparison with Lumbricus terrestris hemoglobin literature data are observed. Their molecular masses were 18,258±30, 16,492±24 and 17,363±17Da, respectively. Two linker chains for HbGp were also observed at 25,817±50 and 26,761±16Da, and this result is different from HbLt, where four linker chains were reported in the range 24–32kDa. Finally, trimers (abc) were observed at 51–52kDa. This partial characterization, performed for the first time, is an important step in the characterization of subunits of this giant extracellular hemoglobin. [Copyright &y& Elsevier]

Summary: The aim of this study was to test the influence of food quality (FQ) (soil, soil+maize stubble and soil+the cover crop Mucuna pruriens), soil moisture (SM) (25%, 33% and 42%) and the presence of the earthworm Pontoscolex corethrurus on the growth and reproduction of the tropical earthworm species Balanteodrilus pearsei. The experiment was carried out in cultures under laboratory conditions for 100 days. The growth rate of B. pearsei in M. pruriens treatments (10.8mgind−1 day−1) was 3.4 and 8.5 times higher than in maize stubble and soil treatments, respectively. The onset of reproductive activity occurred only after mating. Each earthworm fed on M. pruriens achieved a fertility rate 2 times higher (0.58±0.26 cocoons adult−1 day−1) than earthworms fed on maize stubble. M. pruriens also resulted in significant increases of cocoon weights (10.8±1.4mg). Time of cocoon incubation was the same in M. pruriens and maize stubble treatments (20.4±5 days), with one individual hatching per cocoon. The presence of P. corethrurus had no effect on growth, survival or fertility of B. pearsei. This study demonstrated that M. pruriens had positive effects on the growth and reproduction of B. pearsei. Further research is also needed to determine whether M. pruriens decomposition, N release and crop yields are influenced by the earthworm B. pearsei. [Copyright &y& Elsevier]

pH effects on the oligomeric structure of giant Glossoscolex paulistus extracellular hemoglobin in the oxy- and met-forms have been studied as well as effects of the addition of anionic sodium dodecyl sulfate surfactant. A radius of gyration of 110 Â is observed for a macromolecule. At 2 mM surfactant, the radius of gyration diminishes slightly for the oxy-form. However, the extrapolated initial scattering intensity (I(0)) decreases a factor of 2.5, indicating protein dissociation. At 20 mM surfactant, further I(0) decrease is observed, with a reduction of radius of gyration to approximately 30 Â consistent with dissociation into smaller subunits. At pH 9.0, the scattering curves are similar to that obtained for the protein in the presence of 20 ms surfactant at pH 7.0. A radius of gyration of approximately 35 Â shows that the giant hemoglobin dissociation into small subunits also occurs at alkaline pH. From the I(0) value, one can suggest that the tetramer is the main scatter at pH 9.0. At pH 7.0, the met-form dissociates to a larger extent at 2 ms surfactant as compared with the oxy-form, and the main scatters seem to be the 1/12 subunit. At pH 9.0, for the oxy-form, the addition of surfactant does not modify the scattering curve and a radius of gyration approximately 30 Â is obtained, while for the met-form some kind of aggregation is observed. Our results give support to conclude that the iron oxidation state is an important factor modulating the oligomeric dissociation. [ABSTRACT FROM AUTHOR]

Two new species belonging to the new genus Hysterocinetoides are described after protargol staining. They were found in the intestine of worms of the genus Alma (Oligochaeta, Glossoscolecidae) from Cameroon. Their buccal apparatus and kinetosomal infraciliature are typically those of the family Hysterocinetidae. But the sucker has an inverted-U shape and is devoid of skeletal fibers and isolated segments of kineties. These characters justify the creation of the new genus. A review of the diversification of genera among the family Hysterocinetidae is followed by a revision of the systematics of the subclass Hysterocinetia. [Copyright &y& Elsevier]

Abstract: Pontoscolex corethrurus (Müller) is a widespread, peregrine earthworm species of the Glossoscolecidae family, native to the Neotropics. This endogeic earthworm shows wide tolerance to environmental variations, being found in many different habitats and soil types throughout the tropics and sub-tropics. To evaluate the life cycle of this species in tropical artificial soil (TAS), a substrate used in ecotoxicological tests, and the influence of food availability and humidity on its growth, earthworms were incubated individually under laboratory conditions. The life cycle was evaluated in four treatments with 24 earthworms (replicates) each: TAS (120g) without additional food (TAS0), TAS with 5g of horse manure (TAS5), TAS with 10g of manure (TAS10) and TAS with 25% greater soil moisture with 5g of manure (TAS5H). Food was provided every 14d and the containers maintained at room temperature (20±4°C). Cocoons collected in the field were placed individually in the different treatments and the hatching date, growth, development, and reproduction followed for 50 weeks after hatching. New cocoons hatched at 34d, adulthood was reached at 8 months, and cocoon deposition began 3 months later, so that its life cycle was completed in 12 months. By the 13th week all juveniles in TAS0 had died due to insufficient food resources, while in the other treatments, all the animals had matured by 44 weeks, with significantly higher biomass and length in TAS10 (0.72g, 5.4cm), compared with TAS5 and TAS5H (0.59–0.61g, 5.1–5.4cm). Growth and weight gain were positively related to food availability, and no negative effect of excess moisture was observed on their growth. With additional food TAS showed no limitations for the development of the species, and it can be used for ecotoxicological tests involving acute toxicity (mortality) and avoidance, although its potential use in chronic tests (reproduction) is more limited. The length of its life cycle and other biological characteristics associated with this parthenogenetic species create some challenges that must be dealt with before this species can be recommended for wider use as a standard ecotoxicological test species. [Copyright &y& Elsevier]

Abstract: In this paper we summarize the current knowledge on earthworm biodiversity in the State of Paraná, Brazil. Up to the present, 54 species of earthworms are known from the State, belonging to seven families and 19 genera. Native species (N =34), dominated over exotics (N =20). The most widespread exotics were Pontoscolex corethrurus (Glossoscolecidae) and several Amynthas spp. (Megascolecidae) and Dichogaster spp. (Acanthodrilidae), generally associated with anthropogenic sites. Of the native species, most (17 spp.) were in the genus Glossoscolex, frequently encountered in chronically wet soils. Further work is warranted, particularly more sampling efforts, but also ecological studies, given the potential biodiversity and agro-ecological importance of earthworms in Paraná. [Copyright &y& Elsevier]

Abstract: In this paper we present an up-to-date list of the terrestrial earthworms of the state of São Paulo (SP), Brazil. Seventy-seven species are known, of which about 39% are exotic and 61% native, mostly of the Glossoscolecidae (55% of total) and Ocnerodrilidae (17% of total) families. Pontoscolex corethrurus (Müller, 1857) and Amynthas spp. are widespread in the state, while many native species appear to be endemic. Various large-bodied worms (minhocuçus), some intensely harvested for the bait industry, may be endangered. Considering the significance of earthworm activity for soil function, the intensity of land use transformation in Brazil, and the probable existence of new species to be described from SP and other Brazilian states, further sampling efforts and taxonomic training of Brazilian scientists are urgently needed. [Copyright &y& Elsevier]