In English. Summaries in Estonian

Proceedings of the Estonian Academy of Sciences.

Biology. Ecology

Volume 54 No. 4 December 2005

Special issue on Enchytraeidae

Newsletter on Enchytraeidae No. 9


Preface; 251–252

Tarmo Timm

New enchytraeid species since 2002; 253–254

Rüdiger M. Schmelz and Jörg Römbke

Abstract. A list of 21 enchytraeid species (Oligochaeta, Enchytraeidae) new to science described in 2002–2005 is presented.

Key words: enchytraeids, new species.

Estonian Enchytraeidae (Oligochaeta) 2. Results of a faunistic workshop held in May 2004; 255–270

Rüdiger M. Schmelz, Naime Arslan, Roswitha Bauer,  Wim Didden , Klára Dózsa-Farkas, Ulfert Graefe, Irina Panchenko, Andrei Pokarzhevski, Jörg Römbke, Jiři Schlaghamerský, Ùukasz Sobczyk, Zoltán Somogyi, Valerie Standen, Astrid Thompson, Jânis Ventiòð, and Tarmo Timm

Abstract. This paper contains the results of a taxonomic workshop held at the Võrtsjärv Limnological Station on 15–22 May 2004, following the 6th International Symposium on Enchytraeidae. A total of 58 samples were taken from a wide diversity of habitat types; 44 enchytraeid taxa were distinguished, 40 of them were identified to species level. Twelve nominal species are new for Estonia. Of these two species, one each of Achaeta and Fridericia, are new to science; they are described separately in this volume. Further species new to Estonia are: Bryodrilus ehlersi, Buchholzia fallax, Fridericia argillae, F. benti, F. christeri, F. maculatiformis, F. minor, F. rendsinata, F. waldenstroemi, and Mesenchytraeus flavus. The taxonomic status of Timmodrilus oligoseta and Achaeta petseri, species newly described for Estonia in previous papers, is uncertain, they are possibly junior synonyms. One tubificid species was found, Rhyacodrilus falciformis, this being the first record of the species from soil in Estonia. Together with previous publications, there are now 46 enchytraeid species recorded from Estonia.

Key words: Enchytraeidae, soil fauna, protected areas, Estonia.

Achaeta unibulba sp. n., a widespread European species (Oligochaeta, Enchytraeidae); 271–278

Ulfert Graefe, Klára Dózsa-Farkas, and Bent Christensen

Abstract. Achaeta unibulba sp. n. is described from a variety of terrestrial habitats in Europe. The new species is similar to a group of species around A. eiseni Vejdovský, 1878, having bottle-shaped glands (= setal follicles) dorsally and ventrally, the latter being only slightly smaller. Its main distinguishing characters are the fused penial bulbs forming a large roundish body at the ventral midline, the absence of accessory penial glands, the arrangement of clitellum glands, the presence of a large gland at the orifice of the spermathecae, an oesophageal appendage in V without canal leading to pharynx, and the presence of three pairs of preclitellar nephridia. The species occurs in slightly acid to neutral soils. It was found in mineral horizons of mull humus forms as well as in fen peat.

Key words: Oligochaeta, Enchytraeidae, Achaeta, new species, Europe.

Fridericia eiseni sp. n., a new enchytraeid species close to Fridericia ratzeli (Eisen, 1872); 279–291

Klára Dózsa-Farkas

Abstract. Fridericia eiseni sp. n. is described and separated from F. ratzeli (Eisen, 1872) sensu Nielsen & Christensen 1959. The type material has been collected in Hungary and Estonia. The most characteristic features of the new species are its size (15–19 mm long, 0.4–0.5 mm wide), the number of segments (49–61), the maximum of 6 chaetae per bundle, and the shape of the spermatheca (the ampulla is surrounded by 8–9 diverticula of different size, the two lateral ones are always larger). The spermathecal ampulla with the diverticula is quite conspicuous, its diameter may reach 200–350 μm. The ectal duct is long (400–550 μm) and relatively slender (24–26 μm) with one or two small ectal glands. Three subneural glands are present in XIII–XV. The Estonian material is slightly different from the Hungarian as the maximum number of chaetae is 8 and one specimen also had a different size and segment number (24.3 mm long, 0.55 mm wide, and 72 segments). How­ever, due to characteristic, common spermatheca, the Estonian individuals are also included in the newly described species.

Key words: Oligochaeta, Enchytraeidae, Fridericia, new species, Hungary, Estonia.

On the distribution and taxonomic limits of Lumbricillus pagenstecheri (Oligochaeta, Enchytraeidae); 292–301

Tarmo Timm

Abstract. Lumbricillus pagenstecheri (Ratzel, 1869) is the most widely distributed and euryhaline representative of a large, mostly littoral, group of Lumbricillus spp. with distinct glandular cover on the ectal spermathecal duct, and a rosette of glands at its ectal end. It is the only species in this group that has been recorded from the shores of both the Atlantic and Pacific oceans and from soil. A freshwater, maybe landlocked, population lives in Lake Kuril¢skoe (Far East). It is not identical with L. kamtschatkanus Michaelsen (1929), which was previously reported from the same lake. Lumbricillus pagenstecheri as currently recognized is morphologically different from the rich assemblage of related species from marine littoral of the North Pacific while no clear differences are found between its own marine and freshwater populations.

Key words: Lumbricillus, taxonomy, distribution, freshwater fauna.

Oligochaetes (Clitellata) of the Mata Atlântica (Parana, Brazil): first results of the SOLOBIOMA project; 302–309

Jörg Römbke, Rut Collado, and Rüdiger M. Schmelz

Abstract. In the framework of the German–Brazilian SOLOBIOMA project, oligochaete worms (mainly Glossoscolecidae and Enchytraeidae) are being sampled in early, medium, and advanced secondary forests and pastures under different soil conditions in the Brazilian Mata Atlântica (in total 27 sites). One objective of this work is to identify the factors that determine the presence or absence of species. Preliminary results indicate that the species diversity of earthworms is low and does not differ between the various forest and soil types, whereas their abundance and biomass are highly variable. The enchytraeid communities show a different picture with high taxonomic diversity, but low abundance and biomass at nearly all sites.

Key words: Enchytraeidae, Glossoscolecidae, biological soil classification, diversity.

Preliminary study of Enchytraeidae (Oligochaeta) in the Tunca River (Thrace, Turkey); 310–314

Timur Kırgız, Belgin Çamur-Elipek, and Naime Arslan

Abstract. Part of the Tunca River (Tundja) is located in the European part of Turkey, Thrace region. Samples were collected monthly between June 2002 and May 2003 taking duplicates from four stations by using Ekman grab (surface 225 cm2).

During the present study 132 specimens were collected from the Tunca River. As a result of the study, a total of 8 species of Enchytraeida, comprising 1 species from the family Propappidae (Propappus volki) and 7 species from the family Enchytraeidae (Henlea perpusilla, Enchytraeus buchholzi, Cognettia glandulosa, C. sphagnetorum, Cognettia sp., Fridericia sp., and Lumbricillus sp.), were identified. All species in this study are new records for the Turkish segment of the Tunca River.

Key words: Enchytraeidae, Propappidae, Tunca River, Turkey.

Enchytraeid communities in grasslands on peat at different groundwater levels; 315–322

 Wim Didden  and Jerry van Dijk

Abstract. In the Netherlands, wetland restoration projects involve the rewetting of former agri­cultural grasslands, where low water levels are artificially maintained (polders). We studied the effects of rewetting on the enchytraeid community in grasslands on acid peat soil (pH = 3.7). Rewetting was established by hydrologically isolating the restoration areas from the polders. After isolation, the natural seepage conditions of the area caused a clear rise in the groundwater level. At the same time, because of the different quality of the seepage water, the soil pH rose to 5.2–6.7. Sampling was carried out in 2002, four years after the start of the project. It was found that differences in the total abundance and biomass between the enchytraeid communities were not significant. However, there were clear changes in the species composition and diversity. The control site was dominated by Cognettia sphagnetorum, and the rewetted sites by Fridericia species (notably Fgalba and Fperrieri). The diversity was clearly higher in the rewetted sites. In general, the depth distribution of enchytraeid species was not affected by rewetting, Marionina argentea being a notable exception.

Key words: Enchytraeidae, colonization, wetlands, groundwater, decomposition, pH.

A small annelid community (Enchytraeidae, Tubificidae, Aeolosomatidae) during meadow restoration on arable land and in a nearby well-preserved meadow; 323–330

Jiří Schlaghamerský and Klára Kobetièová

Abstract. A small annelid community (Enchytraeidae, Tubificidae, Aeolosomatidae) was studied in a field experiment during meadow restoration on arable land and in a well-preserved meadow nearby. Comparison of the effect of different seed mixtures and spontaneous succession in an abandoned field revealed no significant differences, but a trend to lower densities in plots sown with regional seed mixture compared to some increase in densities with spontaneous succession and those sown with commercial seed mixture was observed. In 2003, i.e. the fifth year of the experiment, dry weather caused very low densities in all treatments as well as in the adjacent arable field. In total, 17 enchytraeid, 1 tubificid, and 2 aeolosomatid species were recorded at the experimental site. In the well-preserved meadow nearby an assemblage of similar species composition with 22 enchytraeid, 1 tubificid, and 1 aeolosomatid species was found.

Key words: Enchytraeidae, Tubificidae, Aeolosomatidae, meadow restoration, grasslands.

Effects of microelements in calcareous loamy chernozem soil on Enchytraeus albidus under laboratory conditions; 331–334

Zoltán Somogyi, Gábor Bakonyi, and István Kiss

Abstract. Effects of six microelements (Cr, Cu, Hg, Pb, Zn and Se) were tested under laboratory conditions on the mortality and reproductive success of Enchytraeus albidus. LOECmortality was 7 mg/kg of available Se and LOECreproduction 2 mg/kg of available Se. No mortality effect was found in the case of available Cr, Cu, Hg, Pb and Zn at rates of 1.5, 131, 17, 167, and 124 mg/kg, respectively, but all these elements in the given concentration decreased reproduction. Available Zn decreased reproduction already at a rate of 47 mg/kg.

Key words: Enchytraeus albidus, microelements, toxicity.

Comparison of the influence of an artificial and a natural soil on the behaviour of Enchytraeus albidus – laboratory tests; 335–341

Mónica Amorim, Amadeu Soares, and Jörg Römbke

Abstract. Enchytraeids are able to avoid unfavourable environmental conditions, especially contaminated areas. Tests were made in order to compare the toxicity in two different soils: OECD artificial soil and LUFA 2.2 natural standard soil. Enchytraeids were exposed to the soils spiked with the fungicides Benomyl and Carbendazim and the herbicide Phenmedipham. The results indicate that the tested soils induced different effects on the organisms: LUFA 2.2 soil was apparently preferred by the organisms and allowed more accurate effect level concentration calculations.

Key words: Oligochaeta, laboratory tests, pesticides, behavioural endpoint.

State-of-the-art: the use of Enchytraeidae (Oligochaeta) as test and indicator organisms in standardized ecotoxicological tests; 342–346

Jörg Römbke, Stephan Jänsch, and Thomas Moser

Abstract. Despite the fact that enchytraeids have been used in ecotoxicological studies for at least three decades, their use has been formalized in standardized guidelines only recently. When including some guideline proposals, all possible investigation levels (laboratory, semi-field (model ecosystems), and field) as well as several endpoints (acute and chronic toxicity, bioaccumulation, and composition of the enchytraeids community) are covered. In this contribution an overview about these activities is given, covering the testing of single chemicals (e.g. pesticides) as well as the assessment of contaminated land. Except lumbricid earthworms no other group of soil organisms is represented so well in terrestrial ecotoxicology.

Key words: laboratory, semi-field, field, monitoring, acute, chronic, bioaccumulation, Oligochaeta.

The effect of potential ice nucleators on the frost survival ability of Enchytraeus variatus (Annelida, Oligochaeta); 347–351

Roswitha Bauer

Abstract. Though enchytraeids occur in harsh climatic environments, they show only moderate eco-physiological capabilities to survive frost under laboratory conditions. Frost survival may be influenced by ice nucleators located in the gut of the worms or attached to their surface. To investigate the effect of substrate composition on the supercooling ability of Enchytraeus variatus, super­cooling points (SCP) of worms and cocoons in two different culture substrates were determined. The SCPs of worms and cocoons cultured in moist nettle leaves were significantly lower than of those cultured in compost, and corresponded with the SCPs of the substrate particles in their environment.

Key words: Enchytraeidae, Enchytraeus variatus, frost survival, supercooling points, ice nucleators, cocoons.

A method for preservation and mounting of Enchytraeidae (Oligochaeta, Annelida); 352–355

Anneke Beylich

Abstract. A method of the fixation, staining, and mounting of enchytraeid worms is described in detail. Common problems are treated and possible variations of the method are discussed.

Key words: fixation, staining, mounting, Enchytraeidae.


Copyright Transfer Agreement; 356

Contents of volume 54; 357–359