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Allolobophora chlorotica (Savigny) An introduced species, found in a few antropogenic locations. Endogeic. Distribution (Fig. 1e): Gomel Reg.: Gomel, 52°25’23.15”N, 31°01’0.27”E, park, 21.10.2020, 14 ex. Vitebsk Reg.: Vitebsk, 55°11’9.86”N, 30°12’2.04”E, park, 05.10.2019, 4 ex. Note: A. chlorotica individuals from Gomel deviated from the typical morphology by the absence of pigmentation., Published as part of Shekhovtsov, Sergei V., Derzhinsky, Yevgeniy A., Ermolov, Sergei A., Kim-Kashmenskaya, Maria N., Poluboyarova, Tatiana V., Kotsur, Vladimir M. & Golovanova, Elena V., 2023, Earthworms of Belarus (Annelida: Megadrili), pp. 38-61 in Zootaxa 5255 (1) on page 46, DOI: 10.11646/zootaxa.5255.1.9, http://zenodo.org/record/7745192

Earthworms enhance plant growth but the precise mechanism by which this occurs is not known. An understanding of the mechanism could potentially support changes in agricultural management reducing fertiliser usage and therefore costs and the carbon footprint of agriculture. We conducted a factorial experiment in which 5 strains of wheat were grown in the presence and absence of earthworms under regular watering and droughted conditions. The different wheat strains all responded in a similar fashion. Plant biomass was greater in the presence of earthworms and under regular watering. The presence of earthworms reduced the impact of drought on plant biomass and also slowed down the rate of drying of the droughted soils. Plant nutrient content (N, P, Si) showed no consistent pattern with treatments but plant total N, P and Si mirrored plant biomass and decreased in the order earthworm-present watered > earthworm-present droughted > earthworm-absent watered > earthworm-absent droughted. Nutrient availability in the soil, as assessed by chemical extractions showed no consistent pattern with treatments. Differential gene expression of plants was greater between watering treatments than between earthworm treatments. Genes that were differentially expressed between the earthworm treatments predominantly related to plant defences, abiotic stress and control of plant growth though a couple were linked to both nitrogen cycling and stress responses. The soil microbiome of the earthworm-present treatments was more associated with nutrient-rich environments, the promotion of plant growth and the suppression of plant pathogens whilst that of the earthworm-absent treatments included a variety of plant pathogens. Our data are consistent with enhanced plant growth being due to changes in the microbiome brought about by earthworm processing of the soil rather than changes in nutrient availability directly due to earthworm activity.

Allolobophora chlorotica L7 MATERIAL COLLECTED. — France • 32 adult specimens, 1 juvenile specimen; Haute-Corse, Cagnano; 42°52’33”N, 9°26’6”E; 150 m a.s.l.; 31.III.2021; T. Decaëns, D. Fernández Marchán leg.; Eco & Sols (BOLD Sample ID: DFM-0118, DFM-0119, DFM-0120, DFM-0121, DFM-0122) • Haute-Corse, Castellare-Di-Casinca; 42°27’39”N, 9°29’27”E; 50 m a.s.l.; 29.III.2021; T. Decaëns, D. Fernández Marchán leg.; Eco & Sols (BOLD Sample ID: DFM- 0093, DFM-0094, DFM-0095, DFM-0096, DFM-0097, DFM- 0099) • Haute-Corse, Ghisonaccia, Marais de Cattolica; 42°1’15”N, 9°28’12”E; 8 m a.s.l.; 2.IV.2021; T. Decaëns, D. Fernández Marchán leg.; MNHN (BOLD Sample ID: DFM-0430, DFM-0431, DFM- 0432, DFM-0433) • Haute-Corse, Oletta, Aliso riparian forest; 42°39’14”N, 9°17’45”E; 24 m a.s.l.; 29.III.2021; T. Decaëns, D. Fernández Marchán leg.; MNHN (BOLD Sample ID: DFM- 0519) • Haute-Corse, Palasca, les Jardins de l’Ostriconi; 42°39’10”N, 9°4’44”E; 6 m a.s.l.; 30.III.2021; T. Decaëns, D. Fernández Marchán leg.; MNHN (BOLD Sample ID: DFM-0561, DFM-0562, DFM- 0563, DFM-0564, DFM-0565) • Haute-Corse, Poggio-d’Oletta, Saint Florent; 42°40’19”N, 9°20’42”E; 49 m a.s.l.; 1.IV.2021; T. Decaëns, D. Fernández Marchán leg.; MNHN (BOLD Sample ID: DFM-0421, DFM-0422, DFM-0423) • Haute-Corse, SantoPietro-di-Tenda, Casta; 42°39’57”N, 9°12’46”E; 251 m a.s.l.; 30.III.2021; T. Decaëns, D. Fernández Marchán leg.; Eco & Sols (BOLD Sample ID: DFM-0291, DFM-0292, DFM-0293, DFM- 0294, DFM-0295, DFM-0296) • Haute-Corse, Sisco, Chapelle Saint Michel; 42°49’22”N, 9°25’58”E; 344 m a.s.l.; 31.III.2021; T. Decaëns, D. Fernández Marchán leg.; MNHN (BOLD Sample ID: DFM-0381, DFM-0382, DFM-0383). REMARKS Five species-level lineages were previously described within A. chlorotica (Dupont et al. 2011) with the geographically restricted L5 (Switzerland and Southeastern France) suggested to be divided into three mitochondrial lineages (L5, L6 and L7). Marchán et al. (2020) attributed the A. chlorotica individuals found in the Hyères Archipelago to L5 (without considering the further subdivision). Specimens collected in Corsica cluster together with this same lineage, except for one specimen more closely related to specimens from Provence and the Alps. Upon closer inspection, both groups appear to be separate cryptic lineages which would correspond to L5 and L7 (as defined by Dupont et al. 2011)., Published as part of Marchán, Daniel Fernández, Gérard, Sylvain, Hedde, Mickaël, Rougerie, Rodolphe & Decaëns, Thibaud, 2022, An updated checklist and a DNA barcode library for the earthworms (Crassiclitellata, Oligochaeta) of Corsica, France, pp. 439-461 in Zoosystema 44 (17) on page 446, DOI: 10.5252/zoosystema2022v44a17, http://zenodo.org/record/7145097, {"references":["DUPONT L., LAZREK F., PORCO D., KING R. A., ROUGERIE R., SYMONDSON W. O. C., LIVET A., RICHARD B., DECAENS T., BUTT K. R. & MATHIEU J. 2011. - New insight into the genetic structure of the Allolobophora chlorotica aggregate in Europe using microsatellite and mitochondrial data. Pedobiologia 54 (4): 217 - 224. https: // doi. org / 10.1016 / j. pedobi. 2011.03.004","MARCHAN D. F., FERNANDEZ R., DOMINGUEZ J., DIAZ COSIN D. J. & NOVO M. 2020. - Genome-informed integrative taxonomic description of three cryptic species in the earthworm genus Carpetania (Oligochaeta, Hormogastridae). Systematics and biodiversity 18 (3): 203 - 215. https: // doi-org. inee. bib. cnrs. fr / 10. 1080 / 14772000.2020.1730474"]}

Allolobophora chlorotica (Savigny, 1826) Enterion chloroticum Savigny 1826: 182. Allolobophora chlorotica Černosvitov 1935: 54; ��apkarev 1972: 76; ��apkarev 1977: 50; Mr��ić 1991: 211; Csuzdi 2012: 97-99. E. Valley meadow, anthropogenic biotopes (Stojanović 1996); forest soils, cultivated soils, meadows (Stojanović et al. 2008; Milutinović et al. 2010). D. Babino selo (Černosvitov 1935); Mostar (��apkarev 1972); Jekovac, Sarajevo, Visoko (��apkarev 1977); Lisina (��ibovi) (Mr��ić 1991). Z. Peregrine species native in the Palearctic., Published as part of Sekuli��, Jovana, Stojanovi��, Mirjana, Popovi��, Filip & Traki��, Tanja, 2022, Checklist of the earthworm fauna of Bosnia & Herzegovina (Oligochaeta: Lumbricidae), pp. 501-518 in Zootaxa 5093 (5) on page 503, DOI: 10.11646/zootaxa.5093.5.1, http://zenodo.org/record/5964425, {"references":["Savigny, J. C. (1826) Analyse des Travaux de l'Academie royale des Sciences, pendant l'annee 1821, partie physique. In: Cuvier, G. (Ed.), Memoires de l'Academie des Sciences de l'Institut de France, Paris, 5, pp. 176 - 184.","Cernosvitov, L. (1935) Monographie des tschechoslovakischen Lumbriciden. Archiv pro Prirodovedecky Vyzkum Cech, 19, 1 - 86.","Sapkarev, J. (1972) Beitrage zur Kenntnis der Lumbricidenfauna Jugoslawiens. Archives of Biological Sciences, Belgrade, 24 (1 - 2), 73 - 86.","Sapkarev, J. (1977) Contribution to the knowledge of earthworms (Oligochaeta: Lumbricidae) from Slovenia, Yugoslavia. Godisen zbornik PMF, 30, 47 - 56.","Mrsic, N. (1991) Monograph on earthworms (Lumbricidae) of the Balkans I, II. Slovenska Akademija Znanosti in Umetnosti, Razred za Naravoslovne Vede, Opera, Ljubljana, 31, 1 - 757.","Csuzdi, C. (2012) Earthworm species, a searchable database. Opuscula Zoologica Budapest, 43, 97. [http: // earthworm. uw. hu]","Stojanovic, M. (1996) Faunisticko-ekoloska studija Lumbricida (Oligochaeta) Srbije. PhD, Faculty of Science, University of Kragujevac, Serbia. [unknown pagination, in Serbian]","Stojanovic, M., Milutinovic, T. & Karaman, S. (2008) Earthworm (Lumbricidae) diversity in the Central Balkans: An evaluation of their conservation status. European Journal of Soil Biology, 44, 54 - 67. https: // doi. org / 10.1016 / j. ejsobi. 2007.09.005","Milutinovic, T., Avramovic, A., Pesic, S., Blesic, B., Stojanovic, M. & Bogdanovic, A. M. (2010) Contribution to the knowledge of pedofauna in Sumadija (Central part of Serbia). Biotechnology & Biotechnological Equipment, 24 (2), 628 - 635. https: // doi. org / 10.1080 / 13102818.2010.10817911"]}

Soil structure is closely linked to biological activities. However, identifying, describing and quantifying soil aggregates remain challenging. X‐ray micro computed tomography (X‐ray μCT) provides a detailed view of the physical structure at a spatial resolution of a few microns. It could be a useful tool to discriminate soil aggregates, their origin and their formation processes for a better comprehension of soil structure properties and genesis. Our study aims to (a) determine different X‐ray μCT‐based aggregate parameters for differentiating earthworm casts belowground (earthworm aggregates) from aggregates that are not formed by earthworms (non‐earthworm aggregates), and (b) to evaluate if these parameters can also serve as specific “tomographic signatures” for the studied earthworm species. For this purpose, we set up a microcosm experiment under controlled conditions during 8 weeks, including three species of earthworms tested separately: the epigeic Lumbricus rubellus, the anecic Lumbricus terrestris and the endogeic Allolobophora chlorotica. Our results show that X‐ray μCT analysis helps distinguish earthworm aggregates from non‐earthworm ones using (a) the relative volume of the components within aggregates and (b) the volumetric mass of aggregates and their global volume. In particular, the volume ratio of mineral grains within the aggregates is significantly different according to earthworm species. So, X‐ray μCT is a powerful and promising tool for studying the composition of earthworm casts and their formation. However, future research is needed to take into account the shapes and spatial distribution of the aggregates' components, in particular the different states of organic matter decomposition. HIGHLIGHTS: Can earthworm belowground casts be differentiated from other soil aggregates using X‐ray μCT? The use of X‐ray μCT for characterizing soil aggregates at a spatial resolution of a few microns. A combination of X‐ray μCT variables discriminates earthworm casts from non‐earthworm aggregates. X‐ray μCT, used alone, is relevant for defining species‐specific signatures of earthworm casts.

We carried out mesocosm experiments using either the anecic earthworm Lumbricus terrestris or the endogeic earthworm Allolobophora chlorotica and loam, silt loam and sandy loam soils to investigate the differing impact of these earthworm of different ecotypes on aggregate formation (percentage water stable aggregates, %WSA) and soil water holding capacity (WHC), two soil properties that underpin many of the ecosystem services provided by soils. Earthworms significantly increased %WSA (by 16–56% and 19–63% relative to earthworm-free controls for L. terrestris and A. chlorotica, respectively). For L. terrestris, this increase was significantly greater in the upper 6.5 cm of the soil where their casts were more obviously present. Allobophora chlorotica treatments significantly increased WHC by 7–16%. L. terrestris only caused a significant increase in WHC (of 11%) in the upper 6.5 cm of the sandy loam soil. Linear regression indicated a consistent relationship between increases in %WSA and WHC for both earthworm species. However, for a given %WSA, WHC was higher for A. chlorotica than L. terrestris likely due to the known differences in their burrow structure. Overall, earthworms increased soil %WSA and WHC but the significant species/ecotype differences need to be considered in discussions of the beneficial impacts of earthworms to soil properties.

Earthworms are an integral part of soil ecosystems, especially for their role in soil functions such as organic matter (OM) decomposition and nutrient cycling. Earthworms and microorganisms are interdependent, and a considerable portion of the contribution earthworms make to influencing OM fate is through interactions with microorganisms. However, the importance of the earthworm-associated microbiome is not fully understood, because it is difficult to separate the direct influence of the earthworms from the indirect influence of their microbiome. Here, we evaluated an antibiotic-based procedure to suppress the microbiome of individuals of ecologically-contrasting earthworm species (Eisenia fetida, Lumbricus terrestris, Allolobophora chlorotica) as the first step towards soil studies aimed at understanding the importance of the earthworm microbiome for host health and function. Individual earthworms were exposed to antibiotics: cycloheximide (150 μg ml−1), ampicillin (100 μg ml−1), ciprofloxacin (50 μg ml−1), nalidixic acid (50 μg ml−1), and gentamicin (50 μg ml−1) either singly or in a cocktail via culture (96 h) in a semi-solid agar carrier. Compared to the non-antibiotic treated control, the cocktail (for all three species) and ciprofloxacin (for E. fetida and A. chlorotica) treatments significantly reduced (P < 0.05) culturable microbial abundance on nutrient agar and potato dextrose agar. The microbial counts were reduced to below detection (

Sulfonated and hydroxy-sulfonated PCBs were recently discovered by our group as new PCB soil contaminants, constituting about 1% of their parent compounds in soil. Here we investigate for the first time the bioaccumulation of these metabolites as well as hydroxy-PCBs and native PCBs in earthworms. A sequence of three experiments, at increasing complexity and ecological realism, were performed with four different earthworm species (Eisenia foetida Savigny, Lumbricus terrestris L, Allolobophora chlorotica Savigny and Aporrectodea caliginosa Savigny) exposed to contaminated soils. The first experiment confirmed that when exposing earthworms to soil contaminated with a single hexa-chlorinated congener (PCB 155), no formation of polar metabolites in earthworms could be detected. This allowed to plan the following two experiments, using a soil from a PCB contaminated site and rich in relatively high levels (10–130 μg kg−1) of hydroxy-, sulfonated-, and hydroxy-sulfonated-PCBs. Bioaccumulation factors (BAFs) and bioconcentration factors (BCFs) were then obtained in the second and third experiments, to compare the accumulation behavior of these chemicals in laboratory and natural conditions. Regressions between BAF/BCF and Log Kow/Log D, produced a variety of results, being generally significant between BCF and PCBs and not significant in the other cases. In general, the metabolites accumulated in earthworms with detectable concentrations in their tissues (8–115 μg kg−1), although sulfonated and hydroxy-sulfonated PCBs showed BAF and BCF values lower (up to two orders of magnitude) than those calculated for the parent PCBs, given their lower lipophilicity.

The current study deals with earthworm biodiversity of Adana Province. Identification was made by examining the earthworm specimens collected in 6 different localities. At the end of the study, 5 species belonging to 3 genus were found: Aporrectodea caliginosa (Savigny, 1826), Aporrectodea trapezoides (Dugès, 1828), Allolobophora chlorotica (Savigny, 1826), Aporrectodea rosea (Savigny, 1826) and Octodrilus transpadanus (Rosa, 1884).

The functioning of soil ecosystems greatly depends on the interactions occurring between soil biota communities. It is well known that earthworms are an important soil component that substantially affects its function, including their meaningful impact on the development of different phytopathogenic soil fungi. Phytopathogenic fungi are responsible for crop disease and cause great economic damage. It has previously been established that earthworms’ coelomic fluid can suppress the growth of phytopathogenic fungi, but the exact molecular mechanism is unknown. The present study aimed at broadening the proof of this observed phenomenon by investigating the effects of the coelomic fluid extract of three different earthworm species (Eisenia andrei, Dendrobaena veneta and Allolobophora chlorotica) on the growth of six different phytopathogenic fungi species (Berkeleyomyces basicola, Fusarium culmorum, Globisporangium irregulare, Rhizoctonia solani, Macrophomina phaseolina, and Sclerotinia sclerotiorum). Coelomic fluid extract was obtained by electrostimulation or usage of extraction buffer (only in case of A. chlorotica) and prepared in three different concentrations by diluting the obtained coelomic fluid with physiological saline. The coelomic fluid extract of the three investigated earthworm species had an inhibitory effect on the growth of all six phytopathogenic fungi species. The greatest inhibitory effect was achieved with the E. andrei coelomic fluid extract reducing the growth of R. solani fungi. The findings of this research confirm the antifungal activity of coelomic fluid obtained from earthworm species belonging to different ecological categories and may be of potential use in crop protection against phytopathogenic fungi.

International audience; Endogeic earthworms live and burrow in the soil to find their food. They burrow by pushing the soil aside or ingesting it and are thus sensitive to soil compaction. However there is a scarcity of data regarding the effects of soil bulk density on the burrowing behavior and activity of endogeic earthworms. We carried out laboratory experiments using repacked soil cores with various levels of bulk density (from 1.18 to 1.38 g cm-3) in which individuals of Aporrectodea caliginosa or Allolobophora chlorotica were incubated for six weeks. The burrow systems inside the soil cores and the compaction around the burrows were then analyzed using X-ray tomography. Soil water infiltration measurements were also carried out. The increase in bulk density had a negative impact on all burrow system characteristics (length, volume, diameter, continuity, number of burrows). When bulk density increased from 1.18 to 1.38 g cm-3, volume, diameter, continuity and the number of burrows decreased on average by 77 %, 21 %, 81 % and 58 %, respectively. The increase in density due to compaction around the burrows was similar whatever the species and the bulk density. Increasing soil bulk density from 1.18 to 1.38 g cm-3 also greatly decreased water infiltration (-89 % for both species) and increased breakthrough time (10 and 25-fold for A. chlorotica and A. caliginosa respectively). However, compared to a control without earthworms, water infiltration in cores incubated with endogeic species was only increased significantly at 1.18 and 1.23 g cm-3. This illustrates that burrows made by endogeic earthworms moderately increase water infiltration and only when the soil bulk density is low. Data provided in this study could be used to refine simulation models of earthworm burrowing behavior where burrowing is assumed to be mainly governed by soil water content, temperature and soil bulk density.

Among the factors modifying the structure of associations and activity of earthworms, the influence of intra- and interspecific interactions has been studied insufficiently. In field experiments the relative importance of these interactions has been compared in lumbricid species that are trophic competitors: in the soil detritophages Allolobophora chlorotica and Aporrectodea caliginosa and in the leaf litter consumers Lumbricusrubellus and L. terrestris. For each species the relative significance of the intra- and interspecific interactions were evaluated by comparison of the state of lumbricid individuals in conditions of low (control) and high population densities in one- or two-species populations. The increase in population density (due to either conspecifics or species-competitor) usually negatively affected the important parameters of the current earthworm generation (growth, mortality, and fecundity), and also of the subsequent generation (numbers and size of the cocoons produced). For three species (except for L. terrestris), trends were revealed indicating the greater strength of intraspecific than interspecific interactions. The species reactions were determined by different factors: by the trophic competition for the litter-dwelling L. rubellus, whereas for the soil dwellers Al. chlorotica and A. caliginosa (in conditions of a surplus of food resources) they were presumably determined by competition for the space.

It is recognised that the establishment and function of soil biota is critical for successful mine residue rehabilitation. Bauxite residues are alkaline, saline and sodic and, whilst methods for establishing vegetation are well studied, little is known about key soil fauna such as earthworms. At a bauxite residue disposal area in Ireland, a 12-year-old rehabilitated residue was examined for evidence of earthworm populations. Five species of earthworm, dominated by Allolobophora chlorotica, were recorded in the rehabilitated residue representing the endogeic, epigeic and epi-anecic ecological groups. To further understand the potential for rehabilitated residues to support earthworm communities, a series of exposure tests was conducted. Whilst unamended residues (pH 10.2, EC 0.629 mS cm−1, ESP 54) was hostile to A. chlorotica survival, 100% survival was observed after 90 days for gypsum and organic-amended residue at salinity of up to 2.9 mS cm−1, possibly due to calcium becoming the dominant cation. Survival of earthworms at salinities higher than anticipated tolerance levels suggests that specific ion dominance plays a role in earthworm survival in saline soils. Percent mass change was negatively correlated with pH, EC and sodium content of the residues. Residue from the 12-year-old site also supported the anecic species Aporrectodea longa over 100 days. Percent mass change in residue samples retrieved from the 12-year-old site was significantly greater (p

International audience; Earthworms are common organisms in soil toxicity-testing framework, and endogeic species are currently recommended due to their ecological role in agroecosystem. However, little is known on their pesticide metabolic capacities. We firstly compared the baseline activity of B-esterases and glutathione-5-transferase in Allolobophora chlorotica and Aporrectodea caliginosa. Secondly, vulnerability of these species to pesticide exposure was assessed by in vitro trials using the organophosphate (OP) chlorpyrifosethyl-oxon (CPOx) and ethyl-paraoxon (POx), and by short-term (7 days) in vivo metabolic responses in soil contaminated with pesticides. Among B-esterases, acetylcholinesterase (AChE) activity was abundant in the microsomal fraction (80% and 70% of total activity for A. caliginosa and A. chlorotica, respectively). Carboxylesterase (CbE) activities were measured using three substrates to examine species differences in isoenzyme and sensitivity to both in vitro and in vivo exposure. CbEs were mainly found in the cytosolic fraction (80% and 60% for A. caliginosa and A. chlorotica respectively). GST was exclusively found in the soluble fraction for both species. Both OPs inhibited B-esterases in a concentration-dependent manner. In vitro trials revealed a pesticide-specific response, being A. chlorotica AChE more sensitive to CPOx compared to POx. CbE activity was inhibited at the same extent in both species. The 7d exposure showed A. chlorotica less sensitive to both OPs, which contrasted with outcomes from in vitro experiments. This non-related functional between both approaches for assessing pesticide toxicity suggests that other mechanisms linked with in vivo OP bioactivation and excretion could have a significant role in the OP toxicity in endogeic earthworms.

Interactions of earthworm species with their environment and in particular the soil they inhabit is poorly understood. In this study, we aimed to use mid infrared absorption (MIR) spectroscopy of earthworm bodies in combination with discriminant analysis of principal components (DAPC), in order to investigate if their biogeochemical composition is determined by their species belonging or the soil they inhabit. Our conceptual approach included the comparison of MIR spectra of four earthworm species (Lumbricus terrestris, Allolobophora chlorotica, Aporrectodea caliginosa and Aporrectodea icterica) sampled from four different agricultural fields in France. Moreover, we tested the influence of the habitat on the earthworm MIR spectra by exchanging individuals and soils in an incubation experiment. MIR spectra varied according to species and sampling site. The MIR spectra of earthworm bodies also changed during the incubation experiment, and for L. terrestris, A. chlorotica and A. icterica depended on the properties of the soil ingested. This suggested that the food source in different habitats impacted the biogeochemical composition of earthworm bodies. DAPC allowed for the identification of earthworm species ranging from 64 to 100% of accuracy (mean 78%). We thus conclude that MIR spectroscopy may be a suitable approach to identify earthworm species, but that their signature may also allow to investigate their ecology as determined by the soil they inhabit.

Accurate species identification is crucial in ecological research on sentinel species such as earthworms. Here, we developed a reliable and cost-efficient method for the rapid identification of taxa within the Allolobophora chlorotica complex of cryptic earthworm species. We combined high resolution melting (HRM) analysis with DNA barcoding (Bar-HRM) in a three-step approach: (i) selection of a mini-barcode in the 16S mitochondrial gene, (ii) test of the method on a panel of 16 reference individuals and (iii) identification at the species level of 24 unknown specimens. Thus, we proved the efficacy of Bar-HRM to discriminate between cryptic sister (or sibling) earthworm species and we provided a standardized method that can be easily adapted to other taxa.

Southeast Iran is located in the arid area, near one of the hottest areas in the word. This area includes several climates, which led to different diverse in soil flora and fauna. In this study, earthworms of southeast Iran were collected. Eight species were identified from 67 samples based on morphological characters. Allolobophora chlorotica (Savigny, 1826) of Lumbricidae family and Amynthas gracilis (Kinberg, 1867) from Megascolecidae family are new records for Iran’s fauna. Five species from Lumbricidae family include Aporrectodea rosea, Aporrectodea trapezoides, Perelia kaznakovi, Eisenia andrei (maybe Eisenia fetida) and Perelia sp. and one species of Megascolecidae, Amynthas corticis, were also identified. Ap. trapezoides, Ap. rosea, and Am. corticis were common species in our study areas. E. andrei (maybe E. fetida) and Am. gracilis, were only found in Baft (Khabr) and Jiroft respectively.

Earthworms directly and indirectly affect soil physico-hydraulic properties. We studied interactions between winter wheat and the common European earthworm Allolobophora chlorotica, testing for impacts upon soil physico-hydraulic properties. Column experiments with three different soil textures and field-relevant earthworm densities were conducted. Saturated hydraulic conductivity (Ks) increased over time in earthworm treatments, with the increase occurring most rapidly in the plant plus earthworm treatment. After 16 weeks Ks had increased in the treatment comprising both plants and earthworms by factors of 12, 34 and 39 in the loam, silt-loam and sandy-loam soils respectively relative to controls. The presence of earthworms resulted in an 88.5% increase in the contribution of pores >3 mm diameter to water flow. In the majority of treatments, soil water-holding capacity and percentage water-stable aggregates of the 5 cm topsoil in both the plant and the earthworm treatments increased significantly compared to controls with the plant plus earthworm treatment showing the greatest increase. Plant growth was greater in the presence than absence of earthworms. Our study shows synergistic and additive effects on soil physical properties in the presence of both earthworms and plants compared to when only earthworms or plants are present. It shows that it is not just vertical-burrowing anecic earthworms that can have a significant effect on soil hydraulic properties but that field-relevant densities of endogeic earthworms such as A. chlorotica can also contribute to soil water flow regulation.

Anaerobic digestion (AD) is used to produce biogas and can offer a solution in waste management. Digestate, the AD by-product, can be applied to soil to improve fertility. However, the response of soil biological communities is not fully understood. There are mixed reports on its impact on earthworm survival. This study aimed to investigate digestate effects on earthworm mortality, and to elucidate potential mechanisms underlying it, if observed, after digestate application to soil. Juvenile and adult Allolobophora chlorotica were used as model organisms and added to microcosms prepared in a glasshouse trial. Five replicated treatments were: liquid Digestate; Osmotic-Stress (i.e. same salt concentration as digestate); Labile-C (i.e. same Biological Oxygen Demand as Digestate); Synthetic-Digestate a mixture of Osmotic-Stress and Labile-C (i.e. same salt concentration and BOD as digestate); and Water as the control. Treatments were applied at two different standardised rates equivalent to the digestate’s N content (i.e. 150 kg N ha−1 eq. or 300 kg N ha−1 eq.). The two development stages of A. chlorotica had different responses to treatments. Adult biomass was significantly greater in the Water control R150 treatment than in Digestate. Significantly lower juvenile biomass was observed in the Digestate R300 treatment than in the Labile-C and Water control treatments. The biomass of adults in the Labile-C R300 treatment was significantly greater than in the Digestate, Osmotic-Stress, Synthetic-Digestate and Water control treatments. Both life-stages exhibited a decline in biomass across all treatments, but the adults had higher mortality rates. The biomass of adults and juveniles declined, respectively, by 90% and 62% for Digestate applied at the lower rate, and by 96% and 90% at the higher rate. Whereas the abundance of adults and juveniles exhibited 80% and 24% drop at the lower rate, and a 90% and 84% drop at the higher rate. This study demonstrates that digestate can have negative impact on earthworm morbidity and mortality when applied to soil at 60% water filed pore space, with most of the total weight loss per pot due to reduced earthworm abundance. A likely hypothesis could be the osmotic stress induced by salts present in the digestate. However, there are other factors that interact with this effect, including possibly anaerobic impacts caused by high water content soils, as well as other mechanisms that have not been fully elucidated through this experimental design. Nevertheless, this work provides the basis for further ecotoxicology studies on the impact of digestate applied to soil. Further, while this works has shown that digestate can negatively impact A. chlorotica survival, whether the same is true for other earthworm species, ecotypes and life-cycle stages warrants further investigation. Considering the important role that worms play in soil health, field scale studies are also required to monitor the impacts of repeated digestate application on earthworm communities.

Increasing commercial application of silver nanoparticles (Ag NP) and subsequent presence in wastewater and sewage sludge has raised concerns regarding their effects in the aquatic and terrestrial environment. Several studies have employed standardised acute and chronic earthworm-based tests to establish the toxicological effects of Ag NP within soil. These studies have relied heavily on the use of epigiec earthworm species which may have limited ecological relevance in mineral soil. This study assessed the influence of Ag NP (uncoated 80 nm powder) and AgNO3 on survival, change in biomass and avoidance behaviour in a soil dwelling (endogiec) species, Allolobophora chlorotica. Earthworms were exposed for 14 days to soils spiked with Ag NP or AgNO3 at 0, 12.5, 25, 50 and 100 mg kg-1 either separately for survival and biomass measurement, or combined within a linear gradient to assess avoidance. Avoidance behaviour was shown to provide the most sensitive endpoint with an observable effect at an Ag NP / AgNO3 concentration of 12.5 mg kg-1 compared with 50 mg kg-1 for biomass change and 100 mg kg-1 for survival. Greater mortality was observed in AgNO3 (66.7%) compared with Ag NP-spiked soils (12.5%) at 100 mg kg-1, attributed to increased presence of silver ions. Although comparison of results with studies employing Eisenia fetida and Eisenia andrei suggest that the A. chlorotica response to Ag NP is more sensitive, further research employing both epigeic and endogeic earthworms under similar experimental conditions is required to confirm this observation.

It is generally accepted that populations of most species experience some level of density dependence; however, this has rarely been shown for soil-dwelling invertebrate species, in particular for earthworms. Experimental data, mostly obtained at high laboratory densities, suggest intense intraspecific competition for resources and/or living space and density-dependent dynamics in earthworm populations, irrespective of their ecological group affiliation. In the present study performed in large field microcosms, I investigated whether density-dependent responses occur within the earthworm density gradients more realistic for the natural sites. Five lumbricid species from epigeic ( Dendrobaena octaedra , Lumbricus rubellus ), endogeic ( Allolobophora chlorotica , Aporrectodea caliginosa ) and anecic ( Lumbricus terrestris ) ecological groups were tested. Soil systems populated with earthworm monocultures in large (20-L) microcosms were exposed in a beech-oak forest for 4.5 months; each species was represented by two ( L. terrestris ) or three treatments forming gradients of increasing density. In two endogeic species, manifold and generally similar density-dependent responses (a retardation of growth, maturation and reproduction rates, but higher mortality rates with density increase) were revealed, likely explained by spatial competition rather than by direct food competition. In each of epigeic species density-dependent responses were less variable and more species-specific. In contrast to endogeics, direct food competition was presumably a more important cause of density-dependence. In L. terrestris no significant density-dependent responses in adult earthworms were revealed; however, they need to be further investigated in relation to the age and territorial behaviour of individual earthworms. Importantly, in any earthworm species the density variations in the reproducing generation had significant consequences for the advancing generation, affecting either the numbers or/and the size (individual weight) of the cocoons produced. It is suggested that an underestimation of density-dependent processes may cause inaccurate estimates of the activities of local lumbricid populations.

Soil dwelling earthworms are now adopted more widely in ecotoxicology, so it is vital to establish if standardised test parameters remain applicable. The main aim of this study was to determine the influence of OECD artificial soil on selected soil-dwelling, endogeic earthworm species. In an initial experiment, biomass change in mature Allolobophora chlorotica was recorded in Standard OECD Artificial Soil (AS) and also in Kettering Loam (KL). In a second experiment, avoidance behaviour was recorded in a linear gradient with varying proportions of AS and KL (100% AS, 75% AS + 25% KL, 50% KS + 50% KL, 25% AS + 75% KL, 100% KL) with either A. chlorotica or Octolasion cyaneum. Results showed a significant decrease in A. chlorotica biomass in AS relative to KL, and in the linear gradient, both earthworm species preferentially occupied sections containing higher proportions of KL over AS. Soil texture and specifically % composition and particle size of sand are proposed as key factors that influenced observed results. This research suggests that more suitable substrates are required for ecotoxicology tests with soil dwelling earthworms.

Phosphorus (P) is an important nutrient for plant growth. However, P is often poorly available for uptake by roots because it strongly adsorbs to the soil mineral phase. Recent research shows that earthworms can temporally and locally increase P availability to plants. However, the pathways through which they do so are not fully understood, and it remains unclear to what extent this capacity varies among earthworm species. Here we study the variation among earthworm species with respect to readily-available P in casts as well as other physico-chemical cast properties, in a greenhouse pot experiment using a soil with a low P status. The earthworms belong to eight commonly occurring earthworm species in the Netherlands: two epigeic species (a mixture of the compost earthworms Dendrobaena veneta/Eisenia fetida; Lumbricus rubellus); four endogeic species (Allolobophora chlorotica, Aporrectodea caliginosa, Aporrectodea rosea, Octolasion lacteum); and two anecic species (Aporrectodea longa; Lumbricus terrestris). For all species, the pH in water extracts of earthworm cast (pH = 7.4–8.2) was significantly higher (p < 0.001) than for the control bulk soil (pH = 6.6) and differed significantly (p = 0.003) among earthworm species. Similarly, the dissolved organic carbon (DOC) concentration in the same water extracts was an order of magnitude higher in earthworm cast compared to the control bulk soil and varied among species (p < 0.001). The size of the total pool of reversibly adsorbed P in earthworm cast was greater than in the control bulk soil, but no significant differences were found among earthworm species. Differences among species were present for the readily-available P pools extracted from casts, including P-Olsen and water-extractable ortho-P. Water-extractable ortho-P concentrations were much higher in the casts of all species as compared to the control bulk soil (0.9–6.8 vs 0.06 mg l−1 or to 9.0–68 vs 0.6 mg kg−1). Highest ortho-P levels were measured in L. rubellus casts and the lowest in casts of A. chlorotica. A positive correlation between the concentrations of DOC and ortho-P was observed (R2 = 0.72, p < 0.001). The observed variation in all measured physico-chemical cast properties could not be explained by conventional ecological earthworm classifications. Our results show that the nature and magnitude of earthworm-induced increased P availability differs dramatically among earthworm species. This strongly suggests that, apart from its size, species composition of the earthworm community is key to optimizing P availability to plants.

Pesticides used to protect plants from pests, threat grievously non-target organisms such as earthworms. Due to their feeding and burrowing activities, earthworms are in direct contact with soil particles and microorganisms, as well as pollutants including pesticides. This work investigated (1) the effect of an organophosphate “ethyl-parathion” on the sensitivity of two endogeic earthworms’ species, Aporrectodea caliginosa and Allolobophora chlorotica; and (2) the role of the gut-microbiota, in synergy with the earthworm’s detoxification pathways, in pesticide tolerance or detoxification. In the first part, biochemical and behavioral responses showed that A. caliginosa is more sensitive to “ethyl-parathion” exposure than A. chlorotica. The endpoints measured ranged from physiological (weight), biochemical (AChE, CbEs, GST) to behavioral biomarkers (cast production and burrowing activity). Our findings showed that the sensitivity of A. caliginosa could be mainly due to the intrinsic sensitivity of its AChE to “ethyl-parathion”. The role of the carboxylesterases, acting as bioscavenger of OP, and the role of the detoxifying enzymes GST did not appear to be efficient mechanisms involved in A. chlorotica tolerance. In the second part, we aimed to characterize the microbiome within the ingested soil, the cast and the gut tissue of A. caliginosa and A. chlorotica in control or polluted soils. Our results showed differences in the microbial composition between these compartments. In this line, we suggested that these two earthworms’ species harbor a species-specific microbiome in their gut. In particular, our findings showed that the earthworm’s gut acts as a “biological filter” for ingested microbial communities during the gut passage. At the level of the gut, we identified four dominated genus within the gut of A. caliginosa versus two dominated genus in the gut of A. chlorotica. Notably, we identified a Rhodococcus strain, which is highly abundant in the gut of A. chlorotica. Previous studies reported Rhodococcus strains for their ability to degrade some group of pesticides. We suggest that the presence of this strain could contribute to the tolerance of A. chlorotica. Finally, we showed that the effect of ethyl-parathion on soil enzyme activities mainly depend on soil texture rather than the presence and/or the species of earthworms. According to our findings, it is of considerable importance to include more than one species to assess toxicity from organophosphorus insecticides, due to the interspecific differences that can occur within the same ecological category. Moreover, the identification and the functional analysis of the microorganisms found in the earthworm’s gut and able to intervene in pesticide detoxification could enhance our knowledge about the fate of the pesticide inside the organism, and could be an important tool for bioremediation program.; Les pesticides utilisés pour protéger les plantes des insectes nuisibles constituent une menace pour les organismes non cibles tels que les vers de terre. En raison de leur activité de bioturbation de sol, les vers de terre sont en contact direct avec les particules et les micro-organismes du sol, ainsi qu'avec les polluants, notamment les pesticides. L‘objectif de ce travail est d‘étudier (1) l‘effet d‘un organophosphoré (OP) «éthyl-parathion» sur la sensibilité de deux espèces de vers de terre endogés, Aporrectodea caliginosa et Allolobophora chlorotica; et (2) le rôle du microbiote intestinal, en synergie avec les voies de détoxification du ver de terre, dans la tolérance ou la détoxification des pesticides. Dans la première partie, les réponses biochimiques et comportementales ont montré que A. caliginosa est plus sensible à l'exposition à «l‘éthyl-parathion» que A. Chlorotica. Les résultats portent sur l‘analyse de biomarqueurs physiologiques (poids), biochimiques (AChE, CbEs, GST) et comportementaux (production de turricules et activité de creusement). Nous avons montré que la sensibilité de A. caliginosa semble liée à la sensibilité intrinsèque de l‘AChE à «l‘éthyl-parathion». De plus, le rôle des carboxylestérases, capables de piéger les insecticides OP, ainsi que le rôle de détoxification des GST notamment, ne semblaient pas être des mécanismes efficaces impliqués dans la tolérance de A. chlorotica. Dans la deuxième partie, nous avons caractérisé, en présence ou non d‘insecticide, le microbiote dans le sol ingéré, les turricules et les intestins des 2 vers de terre. Nos résultats ont montré des différences dans la composition microbienne de ces compartiments. A cet égard, nous avons suggéré que chacune de ces espèces hébergent un microbiote spécifique de l‘espèce dans leur intestin. Nos résultats ont notamment montré que l‘intestin du ver de terre agit comme un «filtre biologique» pour les communautés microbiennes ingérées lors du passage dans l‘intestin. A ce niveau, nous avons identifié, au niveau bactérien, quatre genres dominants dans l'intestin de A. caliginosa et deux genres dominants dans l'intestin de A. chlorotica. Nous avons notamment identifié une souche de Rhodococcus, très abondante dans l'intestin de A. chlorotica. Des études ont montré que des souches de Rhodococcus peuvent dégrader certains groupes de pesticides. Nous suggérons que la présence de cette souche pourrait contribuer à la tolérance de A. chlorotica. Enfin, nous avons montré que l‘effet de l‘éthyl-parathion sur les activités enzymatiques du sol dépend principalement de la texture du sol et non pas de la présence et/ou de l‘espèce de ver de terre.Selon nos conclusions, il est extrêmement important d'inclure plus d'une espèce pour évaluer la toxicité des insecticides organophosphorés, en raison des différences interspécifiques pouvant se produire au sein d'une même catégorie écologique. De plus, l'identification et l'analyse fonctionnelle des micro-organismes présents au niveau de l‘intestin et susceptibles d'intervenir dans la détoxication des pesticides permettraient d‘améliorer nos connaissances sur le devenir du pesticide dans l'organisme et pourraient constituer un outil important dans les programmes de bioremédiation.

While many studies have examined the effects of flooding on earthworm population distributions, few studies have investigated physiological and behavioural responses of earthworms to the low oxygen conditions caused by flooding. An earthworm's skin is its oxygen exchange organ, allowing earthworms to survive in flooded environments provided that the water contains sufficient dissolved oxygen. Individuals of three species of earthworm, the anecic Lumbricus terrestris (Linneaus, 1758), the green morph of the endogeic Allolobophora chlorotica (Savigny, 1826) and the epigeic Lumbricus castaneus (Savigny, 1826) were placed in reconstituted groundwater that was either kept aerated or kept in a sealed container so that dissolved oxygen was gradually consumed as the earthworm respired. Oxygen saturation of the water was measured over time in sacrificial triplicate replicates from each treatment at discrete time points; earthworm mortality and mass were recorded. Before treatments, oxygen levels in all treatment tubes were 9.53 (±0.64) mg O2 L−1. L. terrestris, a large species which emerges at night to forage at the soil surface died when oxygen levels reached 0.82 (±0.46) mg O2 L−1 after approximately 36 h. L. castaneus, a smaller species which lives on the soil surface, died when oxygen levels reached 3.60 (±2.01) mg O2 L−1 after approximately 168 h. A. chlorotica, which is similar in size to L. castaneus, lives in the upper 20 cm of soil and is known to aestivate during the summer, did not die, even when oxygen levels reached 1.49 (±0.40) mg O2 L−1 after 280 h. The results suggest that earthworm respiration is closely linked to both body size and to behavioural ecotype. These findings suggest that if flooding increases in frequency resulting in episodic reductions in soil oxygen levels, the species composition of earthworm communities may change, with an increased presence of endogeic earthworms which show a responsive plasticity to flooding events.

We performed a greenhouse experiment to test how the functional diversity of earthworms, the dominant group of soil macro-invertebrates in many terrestrial ecosystems, affects nitrogen cycling and plant growth. Three species were chosen to represent a range of functional traits: Lumbricus terrestris (large, mainly detritivorous, makes vertical permanent burrows open at the surface), Aporrectodea longa (medium-large, feeds on both detritus and soil, makes burrows more branched than L. terrestris), and Allolobophora chlorotica (small, geophagous, makes ephemeral burrows below the soil surface). Mesocosms with ryegrass (Lolium perenne) were inoculated with none to all three species (similar total biomass), using an experimental design (Simplex) suited to partition single species and diversity effects. Two contrasting N sources, urea or mammalian dung, were labelled with 15N so that the acquisition by plants and earthworms and recovery of applied 15N could be estimated. Over 3 months, plant production was higher with urea applications, but there were also species-specific earthworm effects: A. chlorotica and, to a lesser extent, A. longa increased shoot biomass, whereas L. terrestris increased root biomass. Earthworms did not affect soil N concentrations or leaching losses, whereas more N was leached under urea. A. chlorotica tended to increase dung-15N recovery in grass shoots, but in interaction with A. longa had the opposite effect, possibly through increased N immobilization in the microbial biomass. Earthworms assimilated negligible amounts of urea-15N but a substantial proportion (17% on average) of the dung-15N, with no clear-cut differences between species. Our findings show that earthworm species may have similar trophic response to N sources and yet different effects on plant N uptake and primary production, and that inter-specific earthworm interactions can result in non-additive diversity effects.

By means of a literature survey, earthworm species of significant relevance for soil functions in different biogeographical regions of Europe (Atlantic, Boreal, Mediterranean) were identified. These focal earthworm species, defined here according to the EFSA Guidance Document on the environmental risk assessment (ERA) of genetically modified plants, are typical for arable soils under crop rotations with maize and/or potatoes within the three regions represented by Ireland, Sweden and Spain, respectively. Focal earthworm species were selected following a matrix of four steps: Identification of functional groups, categorization of non-target species, ranking species on ecological criteria, and final selection of focal species. They are recommended as appropriate non-target organisms to assess environmental risks of genetically modified (GM) crops; in this case maize and potatoes. In total, 44 literature sources on earthworms in arable cropping systems including maize or potato from Ireland, Sweden and Spain were collected, which present information on species diversity, individual density and specific relevance for soil functions. By means of condensed literature data, those species were identified which (i) play an important functional role in respective soil systems, (ii) are well adapted to the biogeographical regions, (iii) are expected to occur in high abundances under cultivation of maize or potato and (iv) fulfill the requirements for an ERA test system based on life-history traits. First, primary and secondary decomposers were identified as functional groups being exposed to the GM crops. In a second step, anecic and endogeic species were categorized as potential species. In step three, eight anecic and endogeic earthworm species belonging to the family Lumbricidae were ranked as relevant species: Aporrectodea caliginosa, Aporrectodea rosea, Aporrectodea longa, Allolobophora chlorotica, Lumbricus terrestris, Lumbricus friendi, Octodrilus complanatus and Octolasion cyaneum. Five out of these eight species are relevant for each biogeographical region with an overlap in the species. Finally, the earthworm species Ap. caliginosa (endogeic, secondary decomposer) and L. terrestris (anecic, primary decomposer) were selected as focal species. In the Mediterranean region L. terrestris may be substituted by the more relevant anecic species L. friendi. The selected focal species are recommended to be included in a standardized laboratory ERA test system based on life-history traits. © 2016 Elsevier B.V.