More than one hundred years ago, Bohumil Čejka described peculiar elongate tubules in the posterior region of the intestine of Hepatogaster birulae, a new terrestrial enchytraeid species collected in North-East Siberia. The tubules have no cilia but a proper epithelium and they run parallel to the longitudinal axis of the intestine over several segments, inside the intestinal epithelium but in close contact with the blood sinus. The tubules end blindly anteriorly and with a porus to the intestinal lumen posteriorly. The number of tubules increases from posterior to anterior due to bifurcations, and their diameter decreases. Čejka hypothesized that these tubules are glands that provide secretions for the final process of digestion or that aid in the egestion of faeces. He found them only in one species, Hepatogaster birulae, which was later synonymized with Henlea ochracea. In recent years we screened a large number of terrestrial enchytraeids in vivo and found these peculiar tubules in two further species of Henlea, in one species of Oconnorella and in thirteen species of Fridericia. The pores of these tubules are always located near the transition from midgut to hindgut. The tubules vary among species in extent and branching pattern, and several types can be distinguished. We suggest naming the structures ‘Cejkaian tubules’ in honour and memory of the finder, whose last publication dates from 1914. ‘Cejkaian tubules’ were not found in every species of Henlea and Fridericia, and they seem to be absent in other genera, but techniques other than in vivo light microscopy are required to confirm their absence with certainty. As to their function, we hypothesize the opposite of Čejka, not secretion but resorption, possibly of water, similar to the colon in tetrapod vertebrates.

In the framework of the German-Brazilian project SOLOBIOMA (‘Soil biota and biogeochemistry in the Southern Atlantic rainforests of Brazil’), soil invertebrates were sampled in different regeneration stages of forest: pastures, young, medium and advanced secondary forests as well as old-growth forests. Thirty-nine study sites were located in two private nature reserves situated in neighbouring regions of the southern Atlantic Forest (Mata Atlântica) in Paraná, Brazil. All sites were characterized in terms of climate, history of use (age), vegetation, and soil properties. Here we report on the species diversity of pot worms (Oligochaeta: Enchytraeidae) in these sites, sampled with ISO standard methods. At each site ten soil cores of 5.7 cm diameter were taken once between 2003 and 2008, wet extracted and all pot worms identified alive soon after sampling. Most of the 61 species found in this study were new to science. The enchytraeid fauna of the region is dominated by species of the genera Achaeta, Guaranidrilus and Hemienchytraeus. To date, six species of the genus Achaeta, three species of the new genus Xetadrilus and four species of the species-rich genus Guaranidrilus were described by some of the authors. The terrestrial enchytraeid fauna of Paraná is composed partly of (probably) endemic species (e.g. Achaeta paranensis), partly of species with a known wider distribution within South America (e.g. Hemienchytraeus patricii). Species-poor genera are Fridericia, Enchytraeusand Marionina. On average, enchytraeid abundance was low (i.e. less than 5000 ind m-2). Highest abundance was found in old-growth forests. Species assemblages respond to soil type and vegetation type, and some preferences at the species or genus level could be identified. Due to their small size, low abundance and resulting low biomass enchytraeid worms seem to have little ecological importance in terms of energy flux and nutrient turnover, especially when compared with earthworms. However, due to their species richness they may be useful to indicate the biological status of a site in terms of biological soil quality or perturbation.

The checklist of accepted species of Enchytraeidae in Schmelz & Collado (2012) included 676 species (682 with subspecies). Subsequently, 34 new species and 2 new subspecies were described, and one new genus was erected. Furthermore, several changes in the status of species and genus names occurred (invalidations, revalidations, new combinations). The following lists are meant as a supplement to the checklist in Schmelz & Collado (2012).

This list of new species continues the lists of new enchytraeid taxa published in previous volumes of the Newsletter on Enchytraeidae. Henlea pertoserica, ignored for over 20 years, was kindly brought to our attention by Dr Timm. Achaeta hanagarthi Schmelz, 2008 Achaeta paranensis Schmelz, 2008 Achaeta singularis Schmelz, 2008 Fridericia dianchiensis Chen & Xie, 2008 Fridericia lacii Dózsa-Farkas, 2009 Lumbricillus healyae Rodriguez & Rico, 2008 Henlea pertoserica Popčenko, 1988 Marionina scintillans Boros & Dózsa-Farkas, 2008 Marionina triplex Matamoros, Yildiz & Erséus, 2007

The purpose of this application, under Articles 23.2 and 23.9.3 of the Code, is to conserve the usage of the genus-group name Cognettia Nielsen & Christensen, 1959 (enchytraeidae, Oligochaeta, Annelida) for a genus of annelid worms (type species Pachydrilus sphagnetorum Vejdovský, 1878 (‘1877’)). Cognettia, a name for a Holarctic genus of terrestrial and semi-aquatic annelid worms, is threatened by two subjective senior synonyms, Euenchytraeus Bretscher, 1906 and Chamaedrilus Friend, 1913. If these two names are considered synonyms, Euenchytraeus will replace Cognettia; if they are considered to represent two different genera, Chamaedrilus will replace Cognettia. In 2015 Martinsson et al. adopted the latter course, replacing Cognettia by Chamaedrilus, and allocated its species between both Euenchytraeus and Chamaedrilus. Cognettia is a widely used name and is well-known in the fields of soil biology, ecology, and ecotoxicology, and we propose it be given precedence over Chamaedrilus and Euenchytraeus, which had not been used as valid for almost a century.

Phytotelmata, or plant-held water bodies, often house complex aquatic invertebrate communities. Microdrile oligochaetes (Clitellata, Annelida) are known to be part of that community, but specimens are rarely identified to species level. Here we report three species of Enchytraeidae and three species of Naididae from a collection sampled in phytotelms of bromeliads in Cusuco National Park, Honduras. Two species of enchytraeids are new to science. Bryodrilus hondurensis sp. nov. is distinguished from other members of the genus by the high number of ventral chaetae, up to 11 per bundle. The genus is Holarctic and this is the southernmost record so far of a Bryodrilus species. Hemienchytraeus phytotelmatus sp. nov. is distinguished by a combination of characters, among which the huge spermathecae and seminal vesicles are most conspicuous. The genus is common in tropical and subtropical soils around the world. A third species of enchytraeids in the collection, Cernosvitoviella atrata (Bretscher), is redescribed, together with three known species of Naididae, Pristina jenkinae (Stephenson), Pristina osborni (Walton) and Pristina terrena Collado & Schmelz. Presence of ingested debris and humus in the intestine of most specimens suggests that the collected animals live and reproduce in the phytotelms. We provide a list of oligochaete species recorded so far from bromeliad pools in Central and South America.

This article reviews the current knowledge on terrestrial enchytraeid diversity in Latin America and it outlines the research potential that this group offers. Enchytraeids occur worldwide in all soils with sufficient moisture, oxygen and nutrient supply, but knowledge on their diversity and functioning in the tropics is practically non-existent, except in Latin America. Here, taxonomic efforts and research projects have led to the knowledge of currently 62 terrestrial or semi-aquatic species. Abundance of enchytraeids could be determined at the species level, and differences in the ecological behaviour of species were detected concerning factors such as soil type and land use. Especially South America harbours a rich and idiosyncratic enchytraeid fauna, dominated by genera or species absent or rare in other regions of the world, which is interesting from the phylogenetic point of view. However, only a minute fraction of the actual diversity is known to-date. Seventeen species are possibly peregrines. Densities appear to be comparable to those in temperate regions, from below 10,000 to 270,000 ind.m(-2), suggesting that enchytraeids may be as important for soil processes as in temperate regions. Site-specific species richness makes enchytraeids good biological indicators. Enchytraeids provide a widely open field for research in Latin America ranging from taxonomy and faunistics over biogeography, phylogenetics, comparative morphology, and developmental biology, to fundamental and applied ecology. The widespread ignorance concerning enchytraeids among scientists and naturalists as well as the current taxonomic impediment should be overcome by sound taxonomical and ecological work, training courses, identification manuals and popularization. (C) 2013 Elsevier B.V. All rights reserved.

Five new species of terrestrial Enchytraeidae (Oligochaeta, Clitellata) are described from an experimental field area in Portugal. Achaeta coimbrensis sp. nov. belongs to a group of species without pyriform glands and with lateral spermathecal ectal pores. Fridericia sousai sp. nov., F. roembkei sp. nov., F. marginata sp. nov., and F. ciliotheca sp. nov. have a maximum of four chaetae per bundle and two spermathecal diverticula, a character combination shared by c. 30 other species of this genus. The new Fridericia species are distinguished from these congeners by combinations of characters, but the ventral pattern of the clitellum alone is sufficient to separate the new species from each other. Enchylea heteroducta Nielsen & Christensen, 1963 is redescribed, this being the first record after the original description and the first record from a natural habitat. Further 16 species of enchytraeids are recorded, and there are now 32 species of enchytraeids known from Portugal.

Supplementary notes on the "Guide to European Terrestrial and Freshwater Species of Enchytraeidae (Oligochaeta)" (Schmelz & Collado 2010) are presented. The meaning of the informal categories of "species groups", "species sensu lato" and "species sensu stricto", used in the Guide, is explained. New species to be included are dealt with, notably Enchylea heteroducta Nielsen & Christensen, 1963, Cemosvitoviella longiducta Dumnicka, 2010, Cognettia valeriae Dumnicka, 2010, and Enchytraeus dudichi Dozsa-Farkas, 1995. Several changes in the keys and the species diagnoses are proposed, to improve operability and to include new evidence. Regarding the problem of Enchytraeus crypticus and E. variatus, we propose a classification that differs from the one given in Schmelz & Collado (2010). Instead of synonymizing both species under the name of E. crypticus, we propose to maintain E. variatus at the morphological level. This species sensu lato comprises E. variatus sensu stricto and E. crypticus at the molecular level. Finally we give a page index to species in Schmelz & Collado (2010).

Populations of Enchytraeus that reproduce by fragmentation are distributed worldwide, but their species-level taxonomy is unresolved because morphological differences are inconclusive. Therefore, we compared the isozyme and RAPD-PCR patterns of 5 populations of fragmenting enchytraeids from widely distant localities (Japan, Iran, Greece, and Brazil). Among these populations, 3 were identified (E. japonensis, E. bigeminus, and E. dudichi) and 2 were unidentified. Multiple isozyme bands suggested polyploidy in all investigated populations. In all RAPD-PCR algorithms except 1, the fragmenting group formed a cluster separate from 2 nonfragmenting Enchytraeus species. All 5 populations were clearly separable on the levels of protein and DNA, but the unidentified Greek populations clustered more closely with E. japonensis. It remains unknown whether the fragmenting group in Enchytraeus is monophyletic or polyphyletic. Although every investigated population may deserve species rank, a consistent classification is impossible at present.

An updated checklist of all currently accepted species of Enchytraeidae (Oligochaeta, Clitellata, Annelida) is presented. The list comprises 676 species, which add up to 715 species-group taxa when subspecies and controversial species are included. Species-richest genera are Fridericia (99 species) and Marionina (96 species), followed by Lumbricillus (80 species), Mesenchytraeus (76 species), and Grania (71 species). Six genera are monospecific. Given the generally poor knowledge of Enchytraeidae in most regions on earth, these numbers most probably represent only a minute fraction of the actual diversity, but reasonable estimates as to the actual number of enchytraeid species are not possible at present. For reasons of homonymy, Henlea dicksoni (Nurminen, 1980) and Henlea irkutensis (Nurminen, 1980) are renamed into Henlea dicksoniana and Henlea irkutiana, respectively.

Seven new species of terrestrial Enchytraeidae (Oligochaeta) are described from soils of the southern Brazilian Atlantic rain forest. They were found in the framework of the German-Brazilian project SOLOBIOMA, which studied rain forest recovery. Specimens were investigated in vivo and as stained whole mounts. Three species belong to a new genus, named Xetadrilus. Xetadrilus is similar to Guaranidrilus Cernosvitov, 1937 and Tupidrilus Righi, 1974; it differs in the absence of lateral chaetae from segment VIII on and in peculiar structures of the prostomium: ganglia, inner papillae, and a frontal epithelial recess. Further peculiarities are small body size, absence of oesophageal appendages, and a variable pattern of pharyngeal glands. The three species are named X. maacki, X. aphanus, and X. fabryi. Three further nominal species are transferred to Xetadrilus: Marionina pituca Righi, 1974, Marionina righiana Xie & Rota, 2001, and Stercutus ugandensis Bell, 1954. The other four new species belong to Guaranidrilus, the species-richest genus at the sampling sites. They are named G. andreolii, G. marquesi, G. cingulatus, and G. hoeferi. All species have elongate transverse epidermal gland cells, three pairs of post-pharyngeal ganglia, and a dorsal vesicle in the nephridial postseptale. These traits may be included in the genus diagnosis. In all species described here, most of the species-specific taxonomic traits are found in non-reproductive structures, which means that specimens of all age groups can be identified to the species level, juveniles included.

Littoral oligochaete populations of 82 representative Mountain lakes were sampled throughout the Pyrenees. Forty different oligochaete taxa were collected, and thirty of them were identified to species level. Naididae and Enchytraeidae were found to be dominant in terms of incidence, abundance, and species richness. Measurements of several descriptors relating to the physical and chemical environment, and productivity of each lake, revealed that these two oligochaete groups segregate along the main gradient of environmental variation related to species variance. This environmental gradient was defined by the first ordination axis in a Canonical Correspondence Analysis (CCA), and was mostly related to the variables 'altitude', 'temperature', 'fishless', 'fine substrate', and 'pH'. The segregation patterns observed among the Naididae and the Enchytraeidae mainly occurred relative to the variables 'temperature' and 'fine substrate', and only temperature appeared to explain the observed incidence and abundance patterns found within these two oligochaete groups. Thus, we suggest that temperature, rather than substrate type, is most likely to underlie the observed segregation patterns among the Naididae and the Enchytraeidae. The incidence of the Naididae was positively related to temperature, and this tendency was consistently observed when analysing the frequently observed species within the group, in concordance with the idea that very cold temperatures limit the distribution of the Naididae. In contrast, the abundance of the Enchytraeidae was negatively related to temperature, but this pattern was strongly governed by Cervosvitoviella spp. distribution.

The species composition and relative abundance of the annelid benthic macrofauna (Polychaeta and Oligochaeta) inhabiting the rocky intertidal zone of the ria of Ferrol (Galicia, NW Spain) were studied during field collections, from 2000 to 2002. A total of 14,619 specimens (11,585 polychaetes belonging to 76 species and 24 families and 3,034 oligochaetes belonging to 18 species and two families) were collected from 98 quantitative samples taken from 13 sampling sites. The general spatial distribution of the annelid fauna reflects an increase of the diversity from the inner to the outer part of the ria. The general patterns found in the annelid composition suggest that the assemblages were dominated by oligochaetes in the inner sheltered sampling sites and polychaetes in the outer more exposed sites. Several faunistical and taxonomical remarks on selected species are presented. Two new species of oligochaetes are described: Coralliodrilus artabrensis sp. n. and Pirodrilus fungithecatus sp. n. (Naididae, Phallodrilinae). A new biological index, based on the oligochaete/polychaete ratio (O/P), is proposed as tool to evaluate environmental quality and to monitor future changes in the environment.

Among terrestrial enchytraeid oligochaetes, species of the genus Achaeta are conspicuous by their complete absence of chaetae. Knowledge of Achaeta species in South America is scarce, only four species were known so far. Here we describe three more species of Achaeta from South America, A. hanagarthi, A. paranensis and A. singularis spp. nov., and we provide revised and type-based redescriptions of A. neotropica Č ernosvitov, 1937 and A. piti Bittencourt, 1974. The species were found in the framework of the German-Brazilian project " SOLOBIOMA, Soil biota and biogeochemistry in the Atlantic rainforest of Brazil", which monitors forest regeneration on previously degraded areas by comparing successional stages from pastures to old-growth forests. Species descriptions are based on observations of specimens in vivo and as stained whole mounts; special attention is given to variations among specimens. The three new species are ascribed to a single author (Schmelz). They lack pyriform glands and have spermathecal ectal pores in lateral position. Further distinguishing traits concern the location of preclitellar nephridia, coelomocyte texture, distribution pattern of epidermal and clitellar gland cells, and the inner topography of the prostomium, the latter a new character in Achaeta taxonomy. In A. hanagarthi all sexual organs except the spermathecae are shifted one segment forward. A. singularis is most peculiar by a short and deeply incised brain and by the apparent absence of a suboesophageal ganglion, the ventral ganglia of segments II, III, and IV being separate. This species was only found in forests and is possibly a true representative of the old autochthonous forest soil fauna. A. hanagarthi and A. singularis are similar to the ill-described A. silvatica Nurminen, 1973; the latter is considered as a species inquirenda here. Type reinvestigations revealed that contrary to the original descriptions, A. piti has six segmental pyriform glands and reproductive organs except spermathecae shifted one segment forward, and that A. neotropica has the first preclitellar nephridium at 6/7 and ectal spermathecal pores inlateral position. A. neotropica is highly variable and probably a species aggregate, difficult to resolve with traditional light-microscopical methods. The recently described A. becki Schmelz & Collado 2005 is tentatively included in A. neotropica. The taxonomic descriptions contribute to the general anatomy of the genus; our study further serves as a guide to neotropical species of Achaeta.

A new species of Fridericia (Enchytraeidae, Oligochaeta) is described from soils in Ireland. It was found during sampling campaigns in the framework of a comprehensive taxonomic revision of the genus (Schmelz 2003). Fridericia larix sp. nov., named in reference to the type locality, belongs to the large and taxonomically difficult group of species with two diverticula per spermatheca. It is distinguished from all known congeners by the following combination of characters: (1) a maximum of four chaetae in ventral preclitellar bundles; (2) oesophageal appendages poorly branched; (3) no pharyngeal glands in segment VII; (4) coelomocytes without refractile vesicles; (5) clitellum girdle-shaped, cell distribution alike on all sides; (6) bursal slit of male copulatory organ mainly transverse; (7) no subneural glands; (8) spermathecal diverticula not stalked. Further distinguishing characters are: (9) an asymmetrical arrangement of chaetae in the first lateral postclitellar bundles, with one large chaeta and one small chaeta per bundle, (10) the length ratio of spermatozoa to spermatozoal nuclei (6:1 to 7:1), and (11) a wavy inner surface in parts of the epithelium of the spermathecal ampulla.

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.

A new species of the mainly terrestrial enchytraeid oligochaete genus Achaeta is described from 'terra firme' soils of the Amazonian primary rain forest near Manaus, Brazil. Achaeta becki sp. nov. is about 6 mm long; its main distinguishing characters are a very short vas deferens, thickened septa in almost all segments, and a dorsal blood vessel origin in the clitellar region. Oesophageal appendages, pyriform glands (=setal follicles), and secondary pharyngeal gland lobes are absent. Further distinguishing characters are: pharyngeal glands separate in VI, extending into VII, preclitellar nephridia at 6/7 and 8/9, spermathecal ectal pores lateral. The new species is most similar to A. maorica Benham, 1903, A. neotropica, Cernosvitov, 1937, and A. iridescens Christoffersen, 1979, all from the southern hemisphere. Similarities and differences are discussed in detail.

A new species of the mainly terrestrial enchytraeid oligochaete genus Achaeta is described from 'terra firme' soils of the Amazonian primary rain forest near Manaus, Brazil. Achaeta becki sp. nov. is about 6 mm long; its main distinguishing characters are a very short vas deferens, thickened septa in almost all segments, and a dorsal blood vessel origin in the clitellar region. Oesophageal appendages, pyriform glands (=setal follicles), and secondary pharyngeal gland lobes are absent. Further distinguishing characters are: pharyngeal glands separate in VI, extending into VII, preclitellar nephridia at 6/7 and 8/9, spermathecal ectal pores lateral. The new species is most similar to A. maorica Benham, 1903, A. neotropica Ñernosvitov, 1937, and A. iridescens Christoffersen, 1979, all from the southern hemisphere. Similarities and differences are discussed in detail.

A new species of the oligochaete genus Pristina (Naididae) is described from Central Amazonian soil and litter samples. Investigations were carried out on living and preserved material, with emphasis on characters of the soft-bodied anatomy as seen in living specimens, including the sexual organs. Regarding the chaetal pattern, Pristina trifida is almost indistinguishable from the syntopic P. silvicola Collado & Schmelz, 2000. Conspicuous differences exist, however, in the presence of a stomach with intracellular canals, in the location of the first nephridium in segment IX, and in details of the male reproductive system such as a large prostate gland and a widening of the distal part of the vas deferens. The new species resembles also a group of taxonomically problematic species, P. sima, P. minuta, and P. osborni, whose synonymy has been assumed by several authors. Pristina trifida differs from this group mainly by smaller needle and ventral chaetae and by equally long teeth in the anterior ventral chaetae. The high similarity in the chaetal pattern between P. trifida and P. silvicola implies that there are more species in Pristina than the chaetae might suggest. It further questions the accuracy of chaetae-based species identifications and synonymizations in the group of P. osborni, P. minuta, and P. sima, and possibly the genus in general.