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A new Qinghai-Tibet Plateau species, Rhyacodrilus tanggulaensis Jiang & Cui sp. nov. (Annelida, Clitellata, Naididae, Rhyacodrilinae), is described, and its phylogenetic relationships within the genus is assessed on the basis of both mitochondrial (16S rDNA, COⅠ gene) and nuclear (ITS2) markers. Data from 32 species of Naididae, representing 7 subfamilies and 25 genera are used. Ten species were chosen as outgroup taxa. The molecular data were analyzed by Bayesian inference. The new species is distinguished from other species of Rhyacodrilus by the following combination of characters: dorsal and ventral chaetae with distal tooth 2–3 times longer than proximal, spermathecal and penial chaetae present, atria long and tubular, atrial duct conspicuous. The analyses of the combined molecular data corroborate the close relationship between Naidinae and the rhyacodriline genera Rhyacodrilus, Monopylephorus, and Ainudrilus, and show that the new species is more closely related to R. falciformis, R pigueti, R. okamikae and R. subterraneus, than to R. sinicus, another Chinese species, R. hiemalis and R. coccineus.

A new oligochaete of the family Naididae, subfamily Naidinae, Bratislavia gusevi sp. n., was found in a forest stream in Vietnam. The worm is characterized by small size, asexual reproduction by fragmentation, and dorsal bundles of chaetae beginning from segment II. Each dorsal bundle bears one to two hairs and one to two simple-pointed or bifid, rarely trifid, needle chaetae. An additional distinctive feature of the worm is the presence of one to two enlarged simple-pointed needle chaetae in the bundles of segment IV. These chaetae are somewhat longer and markedly wider than the needles in the rest of the segments. The present paper provides an illustrated description of the discovered individuals and discusses the species’ systematic position, asexual reproduction and regeneration.

During studies of aquatic fauna in wells situated near Kraków (South Poland), many specimens of clitellates were found. The detailed description of the setal formula and genital organs of the collected individuals made it possible to distinguish Haber zavreli (Hrabĕ, 1942) from the related species: H. speciosus (Hrabĕ, 1931) including synonymized H. simsi and its forms known from the USA (H. speciosus simsi and H. speciosus fluminialis) and H. monfalconensis (Hrabĕ, 1966). In addition, remarks concerning the morphologically similar Haber vetus (Semernoy, 1982) described from Lake Baikal and the stygobiotic species H. turquinae (Juget & Lafont, 1979) are included.

Four new actinospore types belonging to the sphaeractinomyxon collective group (Cnidaria, Myxosporea) are described from the coelomic cavity of a marine Baltidrilus sp. (Oligochaeta, Naididae) inhabiting a northern Portuguese estuary. Host identification supports the usage of marine oligochaetes, namely of the family Naididae Ehrenberg, 1828, as definitive hosts for myxosporeans inhabiting estuarine/marine environments. The absence of mixed infections in the host specimens analysed is suggested to reflect the influence of host-, parasite- and environmental-related factors regulating myxosporean–annelid interactions. Molecular analyses matched the SSU rDNA sequences of three of the four new types with those of mugiliform-infecting Myxobolus spp., namely Myxobolus mugiliensis and a Myxobolus sp. from flathead grey mullet Mugil cephalus, and Myxobolus labrosus from thicklip grey mullet Chelon labrosus. These results directly link, for the first time, the sphaeractinomyxon collective group to a myxospore counterpart, further confirming their previously hypothesized specific involvement in the life cycle of myxobolids that infect mullets. Acknowledging this life cycle relationship, the functionality of the sphaeractinomyxon morphotype is suggested to have been decisive for the evolutionary hyperdiversification of the genus Myxobolus in mullets. Unlike other actinospore morphotypes, sphaeractinomyxon lack valvular processes, which implies a limited capability for buoyancy. Considering the benthic-feeding nature of mullets, this feature is most likely crucial in promoting successful transmission to the vertebrate host.

One of the features of the tundra zone is the diversity of freshwater bodies, where, among benthic invertebrates, representatives of Annelida are the most significant component in terms of ecological and species diversity. The oligochaete and leech faunas have previously been studied in two of the three largest lake ecosystems of the Bolshezemelskaya tundra (the Vashutkiny Lakes system, Lake Ambarty and some other lakes in the Korotaikha River basin). This article provides current data on annelid fauna from the third lake ecosystem in the region, Kharbey Lakes and adjacent water bodies. The annelid fauna includes 68 species, including 51 oligochaete species, and 17 species of leeches. For each species, we give information on currently recognised classification, taxonomic synonymy, geographical distribution, findings of the species within the Russian tundra, and brief ecological characteristics.

The freshwater annelid worm genus Limnodrilus, including the widely distributed L. claparedianus Ratzel, 1868, is common in Chinese freshwater ecosystems. One species, previously recognized as morphologically intermediate between L. claparedianus and the North American taxon L. cervix Brinkhurst, 1963, is here described as a new species, L. paraclaparedianus Zhou & Cui n. sp., using both molecular and traditional taxonomy. Comparisons of sequences of the Cytochrome Oxidase subunit I (COI) mtDNA in a sample of Limnodrilus species showed that the distances between species were generally higher than the divergences within them. Phylogenetic analysis of COI as well as 16S mtDNA and Internal Transcribed Spacer 2 (ITS2) nDNA confirmed that the new species is an independent lineage. Moreover, morphological differences in the prostomium, characteristics of the chaetae and internal genitalia support the separation of the species.

An aurantiactinomyxon type is described from the marine naidid Tubificoides pseudogaster (Dahl, 1960), collected from the lower estuary of a Northern Portuguese River. This type constitutes the first of its collective group to be reported from Portugal, and only the fourth described from a marine oligochaete worldwide. Extensive morphological comparisons of new aurantiactinomyxon isolates to all known types without available molecular data are proposed to be unnecessary, given the artificiality of the usage of morphological criteria for actinosporean differentiation and the apparent strict host specificity of the group. Recognition of naidid oligochaetes as the hosts of choice for marine types of aurantiactinomyxon and other collective groups, suggests that the family Naididae played a preponderant role in the myxosporean colonization of estuarine communities. Molecular analyses of the type in study further infer its involvement in the life cycle of Paramyxidium giardi (Cépède, 1906) Freeman and Kristmundsson, 2018, a species that infects the kidney of European eel Anguilla anguilla (Linnaeus, 1758) and that has been reported globally, including from Portuguese waters. The low intraspecific difference registered in relation to Icelandic isolates of P. giardi (0.6%) is hypothesized to result from the emergence of genotypically different subspecies due to geographic isolation.

Allonais inaequalis (Stephenson, 1911) is a well-known “morpho-species” of the subfamily Naidinae with a wide distribution in the world. In this study we describe it, as a new record, from China, and we compare molecular data of A. inaequalis from two geographic populations in China and one in Peru, and we re-evaluate the phylogenetic status of Allonais. Sequence data of both mitochondrial (COI, 12S rDNA and 16S rDNA) and nuclear (18S rDNA and 28S rDNA) from 26 species of naidids (representing 14 of the 22 genera currently recognized) and 7 outgroup taxa were used. The combined data set were analyzed with Bayesian inference and Maximum Likelihood. The different phylogenetic analyses gave largely congruent trees, and they corroborate monophyly of Allonais. The results show that the genetic distances among the three geographic populations of A. inaequalis for COI are 0.0%-7.8% and for 28S vary between 0.0% and 0.8%. Allonais inaequalis falls into two groups, one from China, and one from Peru. We suggest that the Chinese morphotype more resembles A. inaequalis from India, where the species was first described, whereas the species in Peru is likely to be another species.

Tania NJ, Hossain MB, Habib, A, Musa N. 2020. Effects of fish cage culture on macrobenthic communities in a subtropical river. Biodiversitas 21: 3583-3589. The present study described the impact of freshwater fish cage culture on macrobenthic faunal assemblages in the Dakatia River, Chandpur, Bangladesh. The experimental design involved the establishment of four stations in two study sites, two stations near the culture area, and two stations away from culture area. A total of 23 macrobenthic taxa belonging to annelids, molluscs, arthropods, and other minor phyla were recorded from study sites. Oligochaetes were found to be dominant at all four stations composing 42.34% of the total macrobenthos. Pollution indicator benthic organisms i.e., Naididae (30.32%), Tubificidae (20.16%), and Chironomidae (3.54%) were found most in the cage culture area. The density of benthic macrofauna was higher (28,134 inds./m²) in the cage culture site than the non-cage culture site (4,358 inds./m²) due to high abundance of certain pollution tolerant species. However, the values of diversity indices i.e., Species Richness (SR), Shannon-Wiener (S-W) diversity (H´), Pielou’s evenness (E), and Margalef (J) were consistently higher in non-cage culture area than the cage culture area. One-way ANOVA showed no significant variation (P > 0.05) in diversity values between the sites. The results of the present study revealed effects of cage culture on the abundance, diversity, and composition of benthic macrofauna.

The aquatic oligochaete genus Pararhyacodrilus Snimščikova, 1986 included four species, P. aspersus Snimščikova, 1986, the type species, P. palustris (Ditlevsen, 1904), P. ekmani (Piguet, 1928), and P. confusus Semernoy, 2004. Rhyacodrilus palustris (Ditlevsen, 1904) and R. ekmani var. profundalis Lastočkin, 1937, have been associated with Pararhyacodrilus, as a result of different nomenclature-related confusions. A new taxon, Semernodrilus gen. nov., is erected for the Baikalian Pararhyacodrilus confusus Semernoy, 2004. As a result, Pararhyacodrilus includes two species, P. aspersus and P. ekmani.

Two new aquatic oligochaete species are described from tufa barriers in Croatia. The reproductive system in the phallodriline Aberrantidrius mihaljevici Vučković et al. n. sp. conforms to the general pattern in the genus but it is distinguished by a combination of characters, including the shape and length of penial chaetae (3 times the mean length of somatic chaetae), atrium shape and spermathecal pore position (anterior in the postatrial segment). The lumbriculid Stylodrilus tofaceus Rodriguez et al. n. sp. is mainly distinguished from congeners by the spindle-shaped spermathecal ducts with high lining epithelium, and position of the spermathecal pores. These two new taxa reveal that aquatic oligochaete communities in tufa barriers of karstic regions may be of particular interest with respect to diversity of endemic taxa, and also for study of colonization routes of this interesting habitat, with possible relations with groundwaters. The finding of one specimen attributable to the genus Eclipidrilus may open ainteresting research on the biogeography of this Nearctic genus.

International audience; Clitellata is a major clade of Annelida comprising nearly all freshwater and terrestrial annelids as well as several marine species. We investigated clitellate phylogenetic relationships using transcriptomes sampled from 74 taxa (64 clitellates and 10 poly- chaetes), including multiple representatives of nearly all major clitellate higher taxa (Branchiobdellida, Capilloventridae, Crassiclitellata, Enchytraeidae, Haplotaxidae, Hirudinida, Lumbriculida, Moniligastridae, Naididae, Parvidrilidae, Phreodrilidae, Propappidae and Randiellidae). We used a number of filtered data matrices and phylogenetic analyses to examine the effects of data partitioning, missing data and compositional and branch-length heterogeneity and used the resulting phylogenies for divergence time estimation and ancestral habitat reconstructions. All analyses and filtering methods produced a consistent, strongly supported topology in which (a) Enchytraeidae, Hirudinida, Hirudinea (here, Branchiobdellida plus Hirudinida), Lumbriculida, Lumbriculata (Lumbriculida plus Hirudinea), Phreodrilidae and Naididae are monophyletic, (b) a Parvidrilidae + Randiellidae clade is sister to the rest of Clitellata, (c) Phreodrilidae is sister to Naididae, (d) Haplotaxidae is non-mono- phyletic, with some haplotaxids grouping with Crassiclitellata + Moniligastridae, (e) the Phreodrilidae + Naididae clade is sister to all other clitellates except Parvidrilidae + Randiellidae and Capilloventridae, and (f) Lumbriculata is sister to the Crassiclitellata + Moniligastridae + Haplotaxidae (in part) clade. Ancestral habitat reconstructions and divergence time analysis suggested that the most recent common ancestor of Clitellata lived in freshwater during the Devonian (419–359 million years ago) and that all major extant clitellate lineages arose over the next ~150 million years, with multiple lineages subsequently returning to marine habitats or invading land. This study provides a phylogenetic framework for further investi- gation of the geological, environmental and biotic forces and genomic changes that may have impacted clitellate evolution and enabled several major habitat transitions within this group.

The clitellate branchiate genus Branchiodrilus presently includes three nominal species with a mainly tropical distribution. A recent molecular phylogeny of the subfamily Naidinae suggested that species complexes may occur within the genus. In order to delimit species, we studied a total of 91 Branchiodrilus specimens collected in Asia, Africa and Europe; the genus is introduced in the latter area. We used an integrative approach, where genetic data were analysed for 42 specimens (single-locus and multiple-locus methods) and then compared with patterns shown by morphology. Ten Molecular Operational Taxonomic Units could be identified within Branchiodrilus, potentially representing 10 different species. Most of the delimited species are genetically well separated. In contrast, morphological scrutiny identified only three non-overlapping clusters of specimens, one of them grouping all specimens from the Palaearctic region and belonging to the same species. Other morphological groups are mostly consistent with the biogeographic distribution of species. The Oriental region harbours six species and might be the centre of origin from which Branchiodrilus species have dispersed and radiated. Two other species are present in the Afrotropical region, among them B.cleistochaeta newly obtained from the type locality and genetically characterized, but the presence of B.hortensis in Africa is queried. The taxonomic relevance of the morphological criteria traditionally used to distinguish nominal species is useless at the species level. B.hortensis and B.semperi are now considered as species inquirenda. To document the genital organs of species remains highly desirable, although hardly practicable for this species complex with a primarily asexual reproductive mode.

A non-native oligochaete, Bratislavia dadayi (Michaelsen 1905), is recorded from a water body of the cooling system of the Khmelnitsky Nuclear Power Plant (Ukraine). This is the first registration of this species in the central part of the European continent, far from sea and river navigable waterways. The only previous record of B. dadayi in Europe had been from a Belgian estuary. The occurrence in samples taken over several years, and the presence of sexually mature individuals in the Ukrainian population indicate the worm’s successful naturalization in the new habitat. In this paper, we analyze the species’ morphology and abundance in the Ukrainian population and discuss its ecology, current and potential distribution.

In Thalassodrilides cf. briani, the paired ovaries are inconspicuous and polarized structures with developmental gradient of germ cells along their long axis. The about 300 germ cells in the ovary are consolidated into one syncytial cyst and each cell is connected to a common and branched mass of cytoplasm via one stable cytoplasmic bridge. The germ cells differentiate their fate into nurse cells and oocytes. Only one oocyte grows in a given time; it gathers cell organelles and yolk and then it detaches from the gonad. Nurse cells appear to support oocytes development by providing with at least cell organelles. Such observations suggest ovary meroism. T. cf. briani, belonging to limnodriloidin naidids, has the same ovary organization as the representatives of tubificin naidids studied to date. This supports the concept of sister-group relations between Limnodriloidinae and Tubificinae. A similar ovary morphology is also known in several other groups of "microdrile" oligochaetes, which shows that this ovary type is the most widespread among this taxa. Moreover, living in marine or brackish-water sediments, T. cf. briani do not show any significant differences in their ovary structure and oogenesis with freshwater tubificins. This indicates its conservative character independent of the animal life environment.

Lake Baikal is populated by an endemic genus of oligochaetes (Baikalodrilus), which currently comprises 24 morphospecies. The genus can be considered as a ‘species flock’. However, the validity of many species is questionable: the great similarity in their description and the lack of unequivocal diagnostic characters often lead species identification to an impasse. In order to clarify the systematics of this genus, we analysed two nuclear and two mitochondrial DNA markers of 40 Baikalodrilus specimens. DNA and morphological approaches are mostly congruent in suggesting ten candidate species, although two additional species are suspected. A reassessment of the taxonomic value of the morphological characteristics of Baikalodrilus suggests that there are few that can be used as distinctive, specific criteria in the genus. The association between candidate and nominal species remains problematic, except for three species identified prior to molecular analyses. Baikalodrilus trituberculum sp. nov. is described. Phylogenetic inferences suggests that the earliest split in Baikalodrilus and the time of divergence of most lineages corresponding to species are consistent with the hypothesis of a general rearrangement of the Baikal fauna, following major environmental changes due to a general cooling in the Early Pleistocene.

Lake Al-Delmage is part of the middle section of a main outfall drain located south of Baghdad (Iraq). This study focuses on the community structure of aquatic annelids and the physico-chemical variables in this lake. Six stations along the lake were chosen for sample collection in the period from January 2013 to January 2014. The results revealed that the lake water is oligohaline, with salinity levels ranging from 1.5 to 14.6 ‰ and temperatures ranging from 9°C to 33°C; hydrogen ion concentrations (as pH) ranging between 7 and 9. Water was well aerated with dissolved oxygen concentrations values ranging between 6 and 12 mg L−1, and BOD values ranging between 1.5 and 3 mg L−1. The lake water was considered as very hard, since the total hardness values ranging between 825 and 8466 mg L−1. From samples collected during the study period, 1,885 aquatic annelid specimens were identified. Of these, 58% belonged to the family Aeolosomatidae (Polychaeta); the remaining taxa belonged to subfamilies of the family Naididae (Oligochaeta - Clitellata): subfamily Naidinae (6%), subfamily Tubificinae (36%), and subfamily Rhyacodrilinae, Branchiura sowerbyi (3%). Two species of Aeolosomatidae were recognized, Aeolosoma hemprichi and Aeolosoma variegatum. Naidid worms of the subfamily Naidinae included three species, Paranais litoralis, Dero (Aulophorus) furcatus, and Stylaria lacustris. The highest frequency percentage of 23.6% was recorded for P. litoralis. The subfamily Tubificinae was represented by five species - Limnodrilus hoffmeisteri, L. profundicola, L. claparedeanus, L. udekemianus, and Tubifex tubifex. Limnodrilus claparedeanus was the most abundant species, comprising 53% of the total number of Tubificinae. Seasonal fluctuations showed spatial and temporal variations of species richness. The highest species richness was recorded in the stations near the feeder canal, and temporally during June and October 2013.

In this paper, we described the clitellate fauna from an underwater hydrothermal vent zone in Frolikha Bay (Northern Baikal), where a unique community of oligochaetes dominate the zoobenthic communities. In total, twenty one oligochaete species were collected and of these, 19 species belong to the Naididae (former Tubificidae). In addition, one species belonging to the Propappidae, Propappus glandulosus, and another, widespread in the lake, to the Lumbriculidae, Lumbriculus achaetus, were identified. High indices of oligochaete development were revealed in the study which are uncharacteristic for the abyssal zone of Lake Baikal. The hypothesis of possible dependence of species composition and quantitative characteristics of oligochaetes on the development of bacteria Thioploca in the area was not confirmed.

This work deals with the study of the oligochaete groundwater biodiversity in the Dinaric region, a karstic territory extending along the oriental shores of the Adriatic sea. Historical and new data depict a fauna of 123 species, 36 of which are stygobiotic. About 60% of the stygobionts are endemic to this region. Trichodrilus Claparede (Lumbriculidae) and Rhyacodrilus Bretscher (Rhyacodrilinae, Naididae) appear as highly diversified genera (13 and 10 species respectively); their diversification and radiative evolution in ground waters of the Dinaric region can be in relation with the fresh and stable temperatures in this environment, linked to isolate patches of karst. The presence of Parvidrilidae and Rhyacodriloidinae (Naididae) in this region is specially noteworthy; the parvidrilids are a groundwater Holarctic family present in Alabama (USA) and southern Europe and the rhyacodriloidines are a small Palaearctic group found in Lake Baikal and ground waters of the Limestone Alps (Italy) and the Dinaric karst of Slovenia and Croatia. The Phallodrilinae (Naididae) are represented in the Dinaric region by two species of Spiridion Knollner and two species of Abyssidrilus Erseus; both these genera seem to be representatives of two ways of colonization of continental ground waters, the former by migration through waters of decreasing salinity, and the later following the Regression model based on sea transgression and regression. Ground waters of the Dinaric region are confirmed as one of the most important hotspots of biodiversity in the world also for the oligochaete fauna.

A species of marine limnodriloidine oligochaete, Thalassodrilides cf. briani Erseus, 1992 , is recorded from gravelly sand sediments of the subtidal zone in Ehime Prefecture, Japan. The present material agrees with the original description of T. briani, which was first found at Hong Kong, with the exception that the copulatory sacs are oval; not slender. Despite the lack of genetic data for the Hong Kong population, we conclude that the Japanese specimens are conspecific with it, or at least very closely related, based on morphological considerations. This is the first record of the genus Thalassodrilides Brinkhurst and Baker, 1979 in Japan. The phylogenetic relationships between T. cf. briani and three other species of Thalassodrilides are estimated, based on partial DNA sequences of the mitochondrial cytochrome c oxidase subunit I (COI) gene and the complete nuclear ribosomal Internal Transcribed Spacer (ITS) region, using two members of the closely related genus Doliodrilus Erseus, 1984 as outgroups. The genetic analysis shows that T. cf. briani is a species delimited by both mitochondrial and nuclear data, and clearly separated from at least its closely related congeners in the Northwest Atlantic (Caribbean and adjacent areas).

Up to now 17 alien species of family Naididae have been found in Poland. The majority of them have a Ponto-Caspian origin (Potamothrix hammoniensis, P. moldaviensis, P. heuscheri, P. vejdovskyi, P. bavaricus, P. bedoti, Psammoryctides barbatus, P. albicola, P. moravicus, Tubifex newaensis, Isochaetides michaelseni, Paranais simplex and P. frict). Moreover, North American (Quistadrilus multisetosus, Limnodrilus cervix) and thermophilic species from Asia (Branchiura sowerbyi) and South Europe or North Africa (Tubifex blanchardi) have been recorded. Almost all alien species are known from a small number of localities, except for Potamothrix hammoniensis, P. moldaviensis, Psammoryctides barbatus and P. albicola, but only the first of these seems to be an invasive species influencing the composition of benthic communities in the profundal of lakes.

A qualitative survey of freshwater Oligochaeta was conducted in selected districts of Tamil Nadu, India, from October 2013 to June 2015. Thirteen taxa were recorded from a total of 1,915 specimens of freshwater Oligochaeta examined from various random samples. Out of the 13 taxa 10 were identified to the species level, two were identified to genus level and one only to subfamily level. These provided the first reports of Aulophorus furcatus, Dero digitata, D. zeylanica (Naididae) and Pristina breviseta (Pristinidae) for Villupuram, Bothrioneurum sp. (Tubificidae) for Nilagiri, and D. digitata and D. zeylanica for Thiruvannamalai districts. The Dero sp. recorded from Villupuram with four hair and four needle chaetae is uniquely different from the rest of the genus so far reported. The tubificid Limnodrilus hoffmeisteri was the most common and abundant and the only species found in the aquaria. Among the naidids, D. dorsalis was the most abundant species collected from Neithavayal pond (Minjur, Thiruvallur district).

The formation of encapsulated spermatophores is exceptional among aquatic oligochaetes, although it seems to have occurred independently in several unrelated taxa. Among the microdriles, some variations appear unique to single species. The recently described lumbriculid Uktena riparia Fend et al. forms spermatophores in the male duct and attaches them within a deep spermathecal bursa. The attachment of spermatophores to the body wall, in the clitellar region, or in the vicinity of male or spermathecal pores has been reported in Paranadrilus Gavrilov, Bothrioneurum Štolc and some Aktedrilus Knöllner species. Anatomical comparison of reproductive organs suggests convergent development of glandular organs in the male duct or spermathecae, used for the formation, transfer and/or attachment of spermatophores to the concopulant worms. The presence of similar organs in Smithsonidrilus Brinkhurst, where spermatophores have not been reported, is also discussed. Furthermore, a lectotype is designated for Paranadrilus descolei Gavrilov, 1955.

Studies carried out in woodland ponds located in an industrial area of southern Poland revealed the occurrence of a large population of Ripistes parasita (Schmidt, 1847) in one of them. This is a naidid species that is not usually abundant in oligochaete communities. Its ecology and biology is poorly known and thus the aim of this study was to characterise the environmental conditions influencing the occurrence of R. parasita and to assess its population dynamics and life history pattern. R. parasita occurred in a pond with soft water and a low level of mineralisation, a pH ranging from 6.1 to 7.0, and a high content of nitrogen and phosphorus. During our investigation, considerable seasonal changes in the occurrence and population density were detected. Specimens of this species inhabited alder leaf deposits in winter and early spring while in summer and autumn they occupied in large number floating Nuphar lutea leaves. A stepwise regression analysis showed a relationship between the temperature and dissolved oxygen content in the water and the density of R. parasita. The R. parasita reproduced asexually by paratomy (between May and November). The mean doubling time (days) for the population was 22.4. Only a few individuals (less than 1% of the population) matured in September and October.

Heterodrilus is a group of marine Naididae, common worldwide in subtropical and tropical areas, and unique among the oligochaetes by their tridentate chaetae. The phylogenetic relationships within the group are assessed from the nuclear 18S rDNA gene, and the mitochondrial cytochrome c oxidase subunit I (COI) and 16S rDNA genes. Sequence data were obtained from 16 Heterodrilus species and 13 out-group taxa; 48 sequences are new for this study. The data were analysed by Bayesian inference. Monophyly of the genus is corroborated by the resulting tree, with Heterodrilus ersei (a taxon representing a small group of species with aberrant male genitalia) proposed to be outside all other sampled species. Although earlier regarded as a member of the subfamily Rhyacodrilinae, both molecular and morphological data seem to support that Heterodrilus is closely related to Phallodrilinae. However, the results are not conclusive as to whether the genus is the sister group of, or a group nested inside, or separate from this latter subfamily. The studied sample of species suggests at least two major clades in Heterodrilus with different geographical distributions, in one of the clades, most species are from the Indo-West Pacific Ocean, while in the other, the majority are from the Western Atlantic Ocean. Morphological characters traditionally used in Heterodrilus taxonomy are optimized on the phylogenetic tree, revealing a high degree of homoplasy.

Macquaridrilus mcmurtrieae n. sp. is described from Campbell Island. This resembles the only other species in the genus, Macquaridrilus bennettae Jamieson, 1968, in most aspects, but shows significant differences in the anatomy of its genitalia. In particular, the spermathecal pores are dorsal rather than lateral, the spermathecae lack diverticulae, the ejaculatory duct is more stout and muscular, the vas deferens is shorter relative to other organs and the anterior prostate is compact rather than elongate. The presence of a cuticular sperm canal appears to be an apomorphy for the genus. The new species was collected from streams and tarns across the island.http://zoobank.org/urn:lsid:zoobank.org:pub:652AF61D-CFB2-4D07-94C8-59E6FB549D5Fhttp://zoobank.org/urn:lsid:zoobank.org:act:984F2456-768D-48A1-87AD-4453768BAB8A

The Haraz River is one of the most important rivers in the Caspian Sea basin. In order to investigate changes in the taxa abundance composition and feeding groups of the benthic macroinvertebrates, twelve-time sampling was carried out at nine stations along three different sites: (1) before, (2) into, and (3) after Amol City. Results showed impacts of anthropogenic activities caused by the urbanization and development on the occurrence of benthic macroinvertebrates taxa. Families, Hydropsychidae and Heptageniidae at site 1 and Tipulidae at sites 2 and 3, were significantly dominant. The feeding groups of gathering collectors and predators increased from site 1 to site 3, while the filtering collectors and scrapers decreased. Consequently, our data supported the use of the bioindicator concept for Haraz River. Some sensitive (Hydropsychidae, Heptageniidae, Baetidae, and Leuctridae) and tolerant families (Tipulidae and Naididae/Tubificidae) are introduced as potential bioindicators of clean and disturbed river’s area, respectively.

Waterfowl nutritional requirements and food availability at migration stopover habitats may differ from those at nesting or wintering areas. Although there is little information on factors that influence waterfowl diets and food selection during migration, we hypothesized that bird age and wetland density in the surrounding landscape would influence food selection. Thus, the objective of this study was to quantify mallard Anas platyrhynchos and blue-winged teal Anas discors diets during migration and evaluate effects of age and wetland density on waterfowl food selection. We collected 30 mallards and 29 blue-winged teal with food items present in esophagi from wetlands in south-central Nebraska during spring 2008 and 2009. Smartweed Polygonum spp. and barnyard grass Echinochloa spp. were the most common seeds found in both mallards and blue-winged teal, while Naididae and Chironomidae larvae were the most common invertebrates in mallard and blue-winged teal diets, respectively. Invertebrates were consumed by both species in greater proportion than available. Both mallards and blue-winged teal collected in wetland complexes selected some seeds over others, whereas birds in isolated wetlands foraged on foods in proportion to availability. After-hatch-year mallards also selected for some seeds over others, as compared with hatch-year birds, which foraged opportunistically on available foods. If after-hatch-year birds and birds in wetland complexes are able to be more selective in their diets relative to food availability at individual wetlands, they may be able to acquire and replenish lipids reserves more efficiently than hatch-year birds or birds in areas with lower wetland densities.

The A¸sa˘gı Fırat River is located in the south-eastern Anatolia, Turkey. The water quality of the A¸sa˘gı Fırat River basin has been degrading for some time, primarily as the result of pollutants associated with the discharges from numerous domestic and agricultural point sources. Aquatic macroinvertebrate samples were collected from eight lakes conducted by using both hand-nets and an Ekman-Birge grab sampler during the summer and autumn of 2014, focusing on the species composition and distribution of aquatic oligochaetes in eight lakes of the A¸sa˘gı Fırat River basin, and their relationships with physico-chemical parameters measured in those lakes using Principal Component Analysis. Results of analyses of all identified benthic macroinvertebrates clearly indicate the percent dominance of oligochaetes in benthic samples in the eight dam lakes that were sampled: Hacıhıdır lake (62.9%); Atat¨urk lake (49.6%); ¨U¸c¨oz lake (28.9%); Dumluca lake (22.01%); Seve lake (13.9%); C¸ at lake (8.5%); Karakaya lake (7.8%) and Birecik lake (5%). During this study, 1044 oligochaete specimens representing 10 species of two subfamilies within the family Naididae were identified. The most abundant taxa were Limnodrilus hoffmeisteri (48.94%), Potamothrix hammoniensis (19.3%), Tubifex tubifex (13.1%), Nais simplex (5.2%) and Nais communis (4.1%). This study was supported by the Ministry of Forestry and WaterManagement project [‘The establishment of our country Specific Water Quality Ecological Assessment System’]. We are grateful to the Ministry of Forestry and Water Management (Turkey) and DOKAY-C¸ED Environmental Engineering Ltd. Co. (Turkey).

The genus Nais is a group of oligochaetous clitellates, common in eutrophic freshwater habitats. About 30 species are described. Species identification is based primarily on chaetal characters, whi ...

This paper analyses the relationship among mesohabitat and aquatic oligochaete species in the Galharada Stream (Campos do Jordão State Park, state of São Paulo, Brazil). Between August 2005 and May 2006 a total of 192 samples were obtained in areas of four different mesohabitats: riffle leaf litter (RL), pool leaf litter (PL), pool sediment (PS) and interstitial sediment from rocky beds in riffle areas (IS). In the mesohabitats sampled, 2007 specimens were identified, belonging to two families (Naididae and Enchytraeidae). Among the oligochaetes identified Naididae was represented by six genera (Allonais, Chaetogaster, Nais, Pristina, Aulodrilus and Limnodrilus). Principal components analysis (PCA) revealed the first two axes explained 85.1% of the total variance of the data. Limnodrilus hoffmeisteri Claparede, 1862 and Aulodrilus limnobius Bretscher, 1899 were associated with the pool areas (PL and PS). Most species of genera Pristina and Nais demonstrated apparent affinity with the riffle mesohabitats. The Indicator Species Analysis (IndVal) revealed that Nais communis Piguet, 1906, Pristina leidyi Smith, 1896 and Pristina (Pristinella) jenkinae (Stephenson, 1931) are indicative of RL mesohabitat, while family Enchytraeidae was considered indicative of PL mesohabitat.

The main life forms among the Oligochaeta s.l. (= Clitellata) and the related polychaetes are: aquatic (freshwater and marine) sediment-dwellers, inhabitants of the macrovegetation, large and small soil-dwellers, and carnivores. The vegetation-dwellers (Naididae, Pristinidae and Opistocystidae) reproduce mostly in an asexual way; some of them have an ability to swim and posses eyes. A convergent group to the naidid oligochaetes is the aphanoneuran genus Aeolosoma. The smaller Enchytraeidae, and the larger “earthworms” (= Megadrili) Crassiclitellata and Moniligastridae, live in the terrestrial soil. Some Enchytraeidae and Crassiclitellata are secondarily aquatic while some (generally aquatic) tubificids can facultatively live in the soil. Carnivory (as parasitism, commensalism or predation) has been developed in separate genera of several families. A large clade, including the Hirudinea, the Acanthobdellidae and the Branchiobdellidae, is highly adapted for carnivory (suckers, jaws, loss of chaetae...

International audience; Although recognized as an outstanding hotspot of biodiversity for both flora and fauna, the Mercan- tour massif remains almost totally unexplored in terms of its groundwater fauna. This work presents the first overview of groundwater oligochaete assemblages of the Mercantour National Park after a standardized exploration of both consolidated (fractured massif ) and unconsolidated (porous) aquifers. About 40 species of oligochaetes were found at 49 stations representative of the main hydrogeological basins of the Mercantour National Park, from both spring and hyporheic zone habitats. Five stygo- biont species are identified, probably all new to science, of which two are formally described: Aber- rantidrilus stephaniae Martin n. gen., n. sp. (Naididae Ehrenberg, 1828, Phallodrilinae Brinkhurst, 1971) and Marionina sambugarae Schmelz n. sp., a species belonging to the widespread Marionina argentea (Michaelsen, 1889) species complex (Enchytraeidae Vejdovský, 1879). The freshwater sub- terranean species formerly attributed to Abyssidrilus Erséus, 1992 are transferred to Aberrantidrilus Martin n. gen., which means that Abyssidrilus is now restricted to its marine, abyssal species. A dozen of the Mercantour species can be considered as stygophiles. Most stygobiont species are recorded from hyporheic habitats, and stygophiles have a more balanced distribution between both kinds of habitats. The near absence of stygoxene species from the hyporheic zone suggests that this habitat is less affected by the epigean environment than springs. The dominance of enchytraeids among the groundwater oligochaete fauna is here confirmed, and the lumbriculid genus Trichodrilus Claparède, 1862 is also a characteristic faunistic element of the underground freshwater oligochaete communities. The possibility that Aberrantidrilus cuspis n. comb. sensu Sambugar et al. (1999) is a complex of cryptic species is discussed in the framework of recent progress in the knowledge of groundwater biodiversity.; Les oligochètes (Annelida, Clitellata) des eaux souterraines du Parc national du Mercantour (France), avec la description d’un nouveau genre et de deux nouvelles espèces stygobiontes. Bien qu’il soit reconnu comme un remarquable point chaud de biodiversité pour sa flore et sa faune, le massif du Mercantour reste presque totalement inexploré quant à sa faune souterraine. Ce travail rapporte le premier aperçu des assemblages d’oligochètes des eaux souterraines du Parc national du Mercantour, suivant une exploration standardisée des aquifères consolidés (massif fracturé) et non consolidés (poreux). Environ 40 espèces d’oligochètes ont été trouvées dans 49 stations représen- tatives des principaux bassins hydrogéographiques du Parc national du Mercantour, ainsi que des sources et de la zone hyporhéique. Cinq espèces stygobiontes ont été identifiées, probablement toutes nouvelles pour la science, parmi lesquelles deux sont ici formellement décrites, Aberrantidri- lus stephaniae Martin n. gen., n. sp. (Naididae Ehrenberg, 1828, Phallodrilinae Brinkhurst, 1971) et Marionina sambugarae Schmelz n. sp., une espèce appartenant au complexe d’espèces Marionina argentea (Michaelsen, 1889) (Enchytraeidae Vejdovský, 1879) à large répartition. Les espèces d’eaux douces souterraines autrefois attribuées Abyssidrilus Erséus, 1992 sont transférées dans le genre Aberrantidrilus Martin n. gen., restreignant ainsi Abyssidrilus à ses espèces marines abyssales. Douze des espèces du Mercantour peuvent être considérées comme stygophiles. La plupart des espèces sty- gobiontes proviennent des habitats hyporhéiques tandis que les stygophiles se répartissent de façon plus équilibrée entre les deux types d’habitats. La quasi-absence d’espèces stygoxènes dans la zone hyporhéique suggère que cet habitat est moins affecté par l’environnement épigé que les sources. La dominance des enchytréides au sein de la faune des oligochètes des eaux souterraines est ici confirmée, ainsi que le genre Trichodrilus Claparède, 1862 en tant qu’élément faunistique le plus caractéristique des communautés d’oligochètes des eaux douces souterraines. Enfin, la possibilité qu’Aberrantidrilus cuspis n. comb. sensu Sambugar et al. (1999) soit un complexe d’espèces cryptiques est discutée dans le cadre des progrès récents dans la connaissance de la biodiversité des eaux souterraines.

Limnodrilus hoffmeisteri Claparede, 1862 is a cosmopolitan Oligochaeta widely used as indicator of organic pollution in water bodies. Previous contributions have shown the effects of organic matter and temperature on the life history of the species, although very little is known about the factors that influence its reproduction. This study aimed 1) to test whether the larger weight of individuals results in an increase in the reproduction rate and 2) to test the influence of two granulometric fractions of sand on the reproduction and growth the species. In the first experiment, specimens of L. hoffmeisteri were separated in two groups with different average weights (small individuals = 6.63 ± 1.28 mg; large individuals = 12.44 ± 3.99 mg) and kept at 15 ± 1ºC for 21 days. The results of this experiment showed that the number of cocoons was statistically similar between the groups, but the mean number of eggs per cocoon produced by large individuals (2.78 ± 0.35) was greater than that produced by small individuals (7.45 ± 2.50). In the second experiment, weekly observations were conducted for 25 weeks in two groups of 30 specimens: one kept in fine sand and the other in medium sand, at 25 ± 1ºC. The single significant difference was in the number of cocoons per adult per day (0.37 ± 0.22 and 0.23 ± 0.24, for fine and medium sand, respectively). Individuals reared in fine sand produced a greater number of descendants compared to those reared in medium sand in the same period of time.

De Wit P., Erseus C. and Gustavsson L.M. 2011. Ultrastructure of the body wall of three species of Grania (Annelida: Clitellata: Enchytraeidae). —Acta Zoologica (Stockholm) 92: 1–11. The body wall of three species of Grania, including the cuticle, epidermis and the musculature, are studied using TEM. The cuticle is similar to previously studied enchytraeids, with an orthogonal grid pattern of collagen fibers. This pattern is also seen in Crassiclitellata, which has been suggested as the sister taxon of Enchytraeidae. Variation of epicuticular and fiber zone patterns seen in Naididae (formerly Tubificidae and Naididae) seem to be lacking in Enchytraeidae. The fiber thickness, however, varies between Grania species and may be a phylogenetically informative character. The epidermis consists of supporting cells, secretory cells and sensory cells. Basal cells, typical for Crassiclitellata, were not observed. The clitellum of Grania seems to consist of two types of gland cells, which develop from regular epidermal tissue. It is possible that more cell types exist in different regions of the clitellum, however. The body wall musculature is arranged somewhat differently from that of closely related taxa; this refers to the reduction of circular and outer, triangular longitudinal muscle fibers, while the inner, ribbon-shaped longitudinal muscle fibers are well-developed. A search was conducted for the cause of the peculiar green coloration of Grania galbina De Wit and Erseus 2007, and it was concluded that neither cyanobacteria nor epidermal pigment granules were present in the fixed material.

This work summarizes the observations on 30 species of microdriles belonging to the families Naididae (Rhyacodrilinae, Pristininae, Naidinae, Phallodrilinae, and Tubificinae), Phreodrilidae, Lumbriculidae, and Enchytraeidae using scanning electron microscopy. The lumbricid Eiseniella tetraedra, a megadrile species common in typical microdrile habitats, was used for comparison. Microdriles display external ciliate sense structures along the entire body; even at the clitellum and in budding and regeneration zones. According to the shape of the cilia, these sense structures can be divided into receptors of blunt cilia, receptors of sharp cilia, and composed receptors. Sense receptors can be morphologically unconspicuous or clearly defined on sensory buds or papillae. All microdriles studied have receptors of blunt cilia. Enchytraeids have characteristic receptors of short cilia. Pristina (Pristininae), Chaetogaster, Ophidonais, and Stylaria (Naidinae) have receptors of long blunt cilia. Composed receptors were found only in some microdriles and E. tetraedra. Receptors of sharp cilia have been found in most microdriles. Enchytraeids might be the only exception, but sharp cilia are probably present in the amphibiotic Cognettia sphagnetorum. Sensory cells with long sharp cilia might play a rheoreceptor role, and their presence in E. tetraedra and C. sphagnetorum would imply the reappearing of an ancient character that was probably lost with the transit from aquatic to terrestrial habitats. Some lumbriculids have ciliated fields. Anatomically, these structures appear as intermediate between the typical isolate sensory structures of microdriles and the sensillae of the hirudineans. The general pattern in microdriles is that uniciliate receptors and multiciliate receptors are separated, which supports the presumed aquatic origin of the clitellates.

Martin, P., Martinez-Ansemil, E. & Sambugar, B. (2010). The Baikalian genus Rhyacodriloides in Europe: phylogenetic assessment of Rhyacodriloidinae subfam. n. within the Naididae (Annelida). —Zoologica Scripta, 39, 462–482. Two new species of the oligochaete genus Rhyacodriloides Chekanovskaya, Rhyacodriloides aeternorum sp. n. and Rhyacodriloides latinus sp. n., are described from subterranean water bodies of Italy and Slovenia. A comparison with the known species of this genus, Rhyacodriloides abyssalis Chekanovskaya, 1975 and Rhyacodriloides gladiiseta Martin & Brinkhurst, 1998, both from Lake Baikal, shows that the enigmatic ‘cellular masses’ of the latter two species must be interpreted as different, not homologous structures. As a result, R. gladiiseta is to be ascribed to the Phallodrilinae, a primarily marine naidid subfamily, mentioned for the first time in Lake Baikal, and placed in its own genus, Phallobaikalus gen. n. The two new species are morphologically very similar, but their penial setae differ slightly. The phylogenetic relationships of R. latinus sp. n. and R. abyssalis within the Naididae (formerly the Tubificidae) were investigated using a combination of three genes, one nuclear (18S rDNA) and two mitochondrial (12S rDNA and 16S rDNA). A fragment of the mitochondrial COI gene, used as a barcode, also genetically characterized all Rhyacodriloides species. Sequences of 34 Naididae were obtained from EMBL, representative of five naidid subfamilies, and including five oligochaete outgroups. The data were analysed by parsimony, maximum likelihood and Bayesian inference. Taken in combination, the three genes investigated confirm that the two Rhyacodriloides species analysed are closer to each other than to any other naidid species. However, they are separated by 16S and COI distances that amount to 18.5% and 27.2%, respectively, suggesting an ancient separation between species, in good accordance with their present biogeographic distribution. Rhyacodriloides cannot be considered as a rhyacodriline, as assumed so far, as they never appeared related to this subfamily in any analysis considered. In contrast, they appear at the base of a naidid group, including the Tubificinae, the Phallodrilinae, the Limnodrilinae, as well as Branchiura sowerbyi, a species whose phylogenetic association with the rhyacodrilines has been questioned for a long time. Despite a lack of phylogenetic support, this position is congruent with a morphological reassessment of the Rhyacodrilinae, and strongly supports the erection of a new naidid subfamily to accommodate Rhyacodriloides.

Three new species of Tubificinae (Naididae, Oligochaeta), Varichaetadrilus vestibulatus n. sp., Aulodrilus apeniatus n. sp., and Ilyodrilus mesoprostatus n. sp., are reported from Fuxian Lake and Xingyun Lake of Yunnan Province, Southwest China. V. vestibulatus differs from its allies by possessing modified spermathecal chaetae and thinner cylindrical penial sheaths. A. apeniatus is unique in the genus by having no penis. I. mesoprostatus is distinguishable from congeners by its prostate glands joining middle portion of atria and having concave, cone-shaped cuticular penial sheaths. Twenty-eight species of freshwater oligochaetes have hitherto been recorded from Yunnan Province, including five endemic species from three plateau lakes.

Phylogenetic analyses based upon the D3 domain of the nuclear 23S rRNA gene and part of the mitochondrial COI gene indicate that the family Naididae is a subordinate group within the family Tubificidae and most closely related to the subfamily Rhyacodrilinae. Based upon relative genetic distances we hypothesize that the origin of Naididae occurred relatively early in the evolution of Tubificidae, but this was a fairly late event compared to the basic radiation among Annelida.

1 Iwatsuki Senior Highschool, Jonan 1-3-38, Iwatsuki, Saitama, 339-0043 Japan E-mail: springcomes1000times@hotmail.com 2 Department of Natural Science, Faculty of Education, Hirosaki University, Hirosaki, 036-8560 Japan E-mail: ohtaka@cc.hirosaki-u.ac.jp 3 Estonian University of Life Sciences, Centre for Limnology, 61117 Rannu, Tartumaa, Estonia E-mail: tarmo.timm@emu.ee (Received 13 August 2008; Accepted 4 November 2009)

Introduction An important goal for understanding how animals have evolved is to reconstruct the ancestral features and evolution of the nervous system. Many inferences about nervous system evolution are weak because of sparse taxonomic sampling and deep phylogenetic distances among species compared. Increasing sampling within clades can strengthen inferences by revealing which features are conserved and which are variable within them. Among the Annelida, the segmented worms, the Clitellata are typically considered as having a largely conserved neural architecture, though this view is based on limited sampling. Results To gain better understanding of nervous system evolution within Clitellata, we used immunohistochemistry and confocal laser scanning microscopy to describe the nervous system architecture of 12 species of the basally branching family Naididae. Although we found considerable similarity in the nervous system architecture of naidids and that of other clitellate groups, our study identified a number of features that are variable within this family, including some that are variable even among relatively closely related species. Variable features include the position of the brain, the number of ciliary sense organs, the presence of septate ventral nerve cord ganglia, the distribution of serotonergic cells in the brain and ventral ganglia, and the number of peripheral segmental nerves. Conclusions Our analysis of patterns of serotonin immunoreactive perikarya in the central nervous system indicates that segmental units are not structurally homogeneous, and preliminary homology assessments suggest that whole sets of serotonin immunoreactive cells have been gained and lost across the Clitellata. We also found that the relative position of neuroectodermal and mesodermal segmental components is surprisingly evolutionarily labile; in turn, this revealed that scoring segmental nerves by their position relative to segmental ganglia rather than to segmental septa clarifies their homologies across Annelida. We conclude that fine taxonomic sampling in comparative studies aimed at elucidating the evolution of morphological diversity is fundamental for proper assessment of trait variability. Electronic supplementary material The online version of this article (doi:10.1186/s12983-015-0100-6) contains supplementary material, which is available to authorized users.

Despite the importance of Oligochaeta to the dynamics of aquatic ecosystems and to studies of the biology of pollution, there is currently a dearth of information on this group's ecology in Brazil. The aim of this study was to describe the Oligochaeta fauna in four watercourses - three urban and one rural - in the state of São Paulo: the Pinheirinho stream, the Água Branca stream, the Monjolinho River and the Gouveia stream, respectively. Sediment samples were taken with a Van Veen grab in two areas from each watercourse, during the summer and winter of 2001. In all collection areas, measurements of the pH, electrical conductivity, dissolved oxygen and turbidity of the water were made with a Horiba U-10 device. Principal component analysis showed that axes 1 and 2 explained 68.18% of the results' variability, with the first axis predominantly associated with the granulometric data and the second one with the limnological data. Cluster analysis indicated that area II of the Monjolinho River differed from the other collection sites. In the present study, the Oligochaeta group was represented by Tubificidae, Naididae, Alluroididae, Narapidae and Enchytraeidae. Among the three species of Tubificidae, Limnodrilus hoffmeisteri Claparede, 1862, was the most abundant and most frequent species. The results provided important information on the ecology and distribution of limnic Oligochaeta. Apesar da importância dos Oligochaeta para a dinâmica dos ecossistemas aquáticos e para os estudos sobre a biologia da poluição, existe atualmente, no Brasil, uma carência de informação sobre a ecologia desse grupo. O objetivo do estudo foi caracterizar a fauna de Oligochaeta em três córregos urbanos e um córrego rural, localizados na região central do Estado de São Paulo, sendo estes o córrego do Pinheirinho, Água Branca, rio Monjolinho e o córrego do Gouveia, respectivamente. Amostras do sedimento foram obtidas com um pegador Van Veen em duas áreas, durante o verão e inverno de 2001, em cada um dos ambientes estudados. Em todas as áreas de coletas foram tomadas medidas de pH, condutividade elétrica, oxigênio dissolvido e turbidez da água com o aparelho U-10 Horiba. A análise de componentes principais mostrou que os eixos I e II explicaram 68,18% da variabilidade dos resultados, sendo que, o primeiro eixo foi predominantemente explicado pelas variáveis granulométricas e o segundo eixo pelas variáveis limnológicas. A análise de agrupamento indicou que a área II do rio Monjolinho diferiu dos demais pontos de coleta. No presente estudo, o grupo Oligochaeta foi representado pelas famílias Tubificidae, Naididae, Alluroididae, Narapidae e Enchytraeidae. Entre as três espécies de Tubificidae, Limnodrilus hoffmeisteri Claparede, 1862 foi a mais abundante e mais freqüente. Os resultados forneceram informações importantes sobre a ecologia e distribuição de Oligochaeta límnicos.

The development of a new species, Bacillidium vesiculoformis n. sp. (Microspora, Mrazekiidae), is described from the freshwater oligochaete Nais simplex (Oligochaeta, Naididae). Initial stages of parasite development consist of a monokaryotic merogony within a haemocyte of the intestinal blood sinus. The resulting hypertrophied haemocyte is attached to the chloragocytes of the sinus by fine cytoplasmic extensions with the sinus around the cell becoming greatly enlarged. The meronts within the haemocyte form diplokaryotic sporonts that undergo sporogenesis directly within the cytoplasm of the host cell. The infected cell becomes packed with spores and developmental stages, causing it dramatically to increase in size, eventually rupturing the oligochaete and cell. Sporogony appears to be disporoblastic. Released spores were observed to have an adhesive quality. Transmission studies conducted with mature spores failed to transmit the parasite horizontally although vertical transmission was observed. Phylogenetic analysis of the parasite demonstrated that B. vesiculoformis clustered with microsporidian parasites of bryozoa and two other microsporidians, Janacekia debaiseuxi and an unidentified Bacillidium sp.

Many species of Naididae possess a pair of pigmented eyes. Within Clitellata, eyes are generally present in Hirudinea, whereas Naididae are the only oligochaete taxon having these sense organs. The eyes of Naididae are epidermal structures and consist of a multicellular pigment cup in which a single row of five to six photoreceptor cells is embedded. The sensory cells are typical phaosomes: the photoreceptive structures (microvilli) project into a cavity formed by the sensory cell itself. In Stylaria lacustris this cavity opens to the exterior, clearly documenting that it represents an invagination of the apical cell membrane. The density of sensory microvilli is comparatively low and a central vitreous body is lacking. Similar phaosomous photoreceptors, not associated with either pigmented or unpigmented supporting cells, occur in the epidermis of the anterior end. These photoreceptors correspond to those found in other Clitellata, confirming that phaosomes are the only known type of photoreceptor cell occurring in this taxon. As a result of their simple structure they have been regarded as plesiomorphic for Annelida. However, an out-group comparison with eyes and photoreceptors occurring in polychaetes and other spiralians reveals that they, in fact, are a rather specialized type of photoreceptor. Despite the simple structure, they most likely represent an autapomorphy of Clitellata. It follows that in all probability, these phaosomes are a secondarily evolved type of photoreceptor, which arose within the oligochaete clade after the primary photoreceptors present in the out-groups had been lost. This loss might have occurred during evolution of a burrowing life style within the sediment and subsequent invasion of the terrestrial environment. Zusammenfassung Viele Arten der Naididae besitzen ein Paar pigmentierter Ocellen. Innerhalb der Clitellata sind Augen nur bei Hirudinea generell vorhanden, wahrend die Naididae das einzige augentragende Taxon der Oligochaeten sind. Die Ocellen der Naididae sind epidermale Bildungen und bestehen aus einem multizellularen Pigmentbecher, in den eine Reihe von 5–6 Photorezeptorzellen eingebettet ist. Die Sinneszellen sind typische Phaosome: die photosensitiven Strukturen (Mikrovilli) ragen in eine Hohle, die von der Sinneszelle selbst gebildet wird. Bei Stylaria lacustris ist dieser Raum nach ausen offen und demonstriert so seine Entstehung als Einfaltung der apikalen Zellmembran. Die Dichte der Mikrovilli ist relativ gering und ein zentraler Glaskorper ist nicht vorhanden. Ahnliche phaosomale Photorezeptoren, die weder mit pigmentierten noch mit unpigmentierten Stutzzellen assoziiert sind, kommen in der Epidermis des Vorderendes vor. Diese Lichtsinneszellen entsprechen vollkommen den sonst bei Clitellata vorhandenen und bestatigen so, dass Phaosome den einzigen Photorezeptortyp darstellen, der in diesem Taxon vorkommt. Aufgrund ihrer einfachen Struktur sind sie als eine Plesiomorphie der Annelida interpretiert worden. Ein Ausengruppenvergleich mit Augen und Photorezeptorzellen von Polychaeten und anderern Spiralia belegt jedoch, dass sie tatsachlich einen sehr spezialisierten Typ von Photorezeptoren darstellen. Deshalb sind sie trotz ihrer einfachen Struktur hochstwahrscheinlich eine Autapomorphie der Clitellata. Daraus folgt, dass sie aller Wahrscheinlichkeit nach ein sekundar evolvierter Photorezeptortyp sind, der in der Stammlinie der Clitellata entstand nachdem die primaren Photorezeptorzellen verlorengegangen waren. Ein derartiger Verlust konnte wahrend der Evolution einer grabenden Lebensweise innerhalb des Sedimentes und darauf folgender Etablierung terrestrischer Lebensraume erfolgt sein.

A total of 15 taxa of aquatic oligochaetes have been identified in two collections, one of which was from Coiba island, at the National Museum of Natural Sciences (MNCN, Madrid), and the other from Cuba (leg. Dr. Ana Camacho). Morphological and systematic remarks are provided for Limnodrilus variesetosus, Pristina aequiseta forms evelinae and foreli, P. breviseta, P. osborni, and P. sima. Pristina cabacuensis Botea, 1983 and P. decui Botea, 1987 are proposed as junior synonyms of Pristina aequiseta Bourne. The taxonomy of Pristina osborni and P. sima is discussed and their independent specific status supported. The alluroidid Brinkhurstia americana is reported from Coiba island widening the known geographical distribution of the species to South and Central America.Un total de 15 taxones de oligoquetos acuáticos han sido identificados en dos colecciones de la isla de Coiba del Museo Nacional de Ciencias Naturales (MNCN, Madrid) y Cuba (leg. Dra. Ana Camacho). Se aportan notas morfológicas y sistemáticas para las especies Limnodrilus variesetosus, Pristina aequiseta formas evelinae y foreli, P. breviseta, P. osborni y P. sima. Pristina cabacuensis Botea, 1983 y P. decui Botea, 1987 son propuestas como sinónimos de Pristina aequiseta Bourne. Se discute la taxonomía de Pristina osborni y P. sima y se apoya su estatus de especies independientes. El alluroidido Brinkhurstia americana se cita en la isla de Coiba ampliando la distribución actual de la especie a America Central y del Sur.

Haploid genome sizes (C-values) were estimated for 12 species of freshwater oligochaetes (families Naididae and Tubificidae) and 15 species of earthworms (families Lumbricidae and Megascolecidae). Aquatic worms ranged in genome size from about 0.8 to 7.6 pg, while earthworms varied from approximately 0.4 to 1.2 pg. Interspecific differ- ences in nuclear DNA content did not appear to be linked to variation in chromosome number, but there was evidence of cryptopolyploidy in the aquatic worms. No correlations were found between genome size and either body size or life-history traits, although there may be an association between higher DNA content and parthenogenetic reproduction in earthworms. Resume : Nous avons estime la taille du genome haploide (les valeurs de C) de 12 especes d'oligochetes d'eau douce (familles Naididae et Tubificidae) et de 15 especes de vers de terre (familles Lumbricidae et Megascolecidae). Le genome des vers aquatiques varie en taille d'environ 0,8 a 7,6 pg, alors que celui des vers de terre va d'environ 0,4 a 1,2 pg. Les differences interspecifiques de contenu d'ADN nucleaire ne semblent pas reliees a la variation du nombre de chromosomes, mais il y a des indices de l'existence de cryptopolyploidie chez les vers aquatiques. Il n'y a pas de correlation entre la taille du genome d'une part, et la taille du corps et les caracteristiques du cycle biologique d'autre part, bien qu'il puisse y avoir une association entre le contenu plus eleve d'ADN et la reproduction parthenogenetique chez les vers de terre. (Traduit par la Redaction) 1489

The Potamodrilidae are small limnetic annelids of apparently simple organization and uncertain phylogenetic position. This group, which was regarded either as a subtaxon of the Aeolosomatidae or united with the Aeolosomatidae as Aphanoneura, has been placed in various positions within the Annelida: (1) at the base of the Clitellata, (2) as a highly derived clitellate taxon closely related to the Naididae, or (3) excluded from the Clitellata because of fundamental differences in the reproductive system and the lack of a clitellum. Moreover, a sister-group relationship between the Aeolosomatidae and Potamodrilidae has been questioned as well. The results of an immunohistochemical (cLSM) and ultrastructural analysis of the central nervous system in Potamodrilus fluviatilis support an exclusion from the Clitellata. The circumoesophageal connectives enter the brain through dorsal and ventral roots, a situation unknown in Clitellata but generally occurring in polychaetes. The ciliated pits, located in front of the brain, are not nuchal organs as previously thought but different sensory structures. However, modified nuchal organs are present behind the brain close to the ventral roots of the circumoesophageal connectives in a position corresponding to that of the nuchal organs found in Aeolosoma spp. Such organs are characteristic for polychaetes and absent in clitellates without exception. These morphological results clearly support the removal of the Potamodrilidae from the Clitellata. Furthermore, the characters present in the nervous system and sense organs show a general correspondence between the Potamodrilidae and the Aeolosomatidae.

Four species of Tubificinae (Oligochaeta: Naididae), Tubifex laxus n. sp., Tubifex gracilentus n. sp., Tubifex conicus He, Wang & Cui, 2012, and Tubifex tubifex (Müller, 1774) are reported from Tibet, China. T. laxus n. sp. is distinguished from allied species by relatively wide atria. T. gracilentus n. sp. differs from congeners in extremely thin and long penial sheaths. T. conicus is redefined as a species that lacks spermathecae. T. tubifex as redescribed here has slightly hirsute hair chaetae, cuticle rings around the penes and spermathecae with empty ampullae.

This is a catalogue of 1081 new nominal taxa and 372 new combinations or names with new ranks of available scientific names given to the oligochaetes in freshwater and marine families that have been described since the publication of the monograph by Brinkhurst & Jamieson (1971) and its supplement (Brinkhurst & Wetzel 1984). Eight names are listed for the family Alluroididae, seven for the Capilloventridae, 26 for the Haplotaxidae, 144 for the Lumbriculidae, 75 for the Naididae, two for the Opistocystidae, 11 for the Parvidrilidae, 51 for the Phreodrilidae, 34 for the Pristinidae, six for the Randiellidae, one for the Tiguassidae, and 1088 for the Tubificidae. In the Propappidae and the Narapidae there are no new names or combinations subsequent to 1984. Families with predominantly terrestrial species are excluded from this paper. More than half of the species-group names, 54.4%, belong to marine taxa.

One new species of Naidinae (Oligochaeta, Naididae), Nais badia sp. n. and one new record species from China, Tubifex montanus Kowalewski, 1919 (Tubificinae) are found in southern Tibet. The new species is distinguished from congeners by its large area of reddish brown pigment in the anterior segments I–VIII, serrate hairs, pectinate needles with 1–2 intermediate teeth, ventral chaetae partly with 1–2 fine intermediate teeth and wave-like movements. The new material of the species Tubifex montanus differs slightly from the previous descriptions by its vas deferens entering atrium subapically, wide ental end of penial sheath and smooth hair chaetae.