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In this study, an updated list of Turkish earthworm species is presented. In the last five years, several new species were added to the earthworm fauna of Turkey namely: Amynthas morrisi, Dendrobaena cevdeti, Dendrobaena cognettii, Dendrobaena pavliceki, Dendrobaena szalokii, Dendrobaena taurica, Eisenia andrei, Eisenia kontschani, Eisenia patriciae, Healyella zicsii and Octolasion cyaneum. According to the current list, 87 taxa have been recorded so far. Two of these taxa belong to Acanthodrilidae, one taxon of Criodrilidae, 80 taxa of Lumbricidae and four taxa of Megascolecidae; 32 taxa are endemic for the territory of Turkey. [ABSTRACT FROM AUTHOR]

Tetraonchidae is a small and relatively monomorphic family of dactylogyroid monogeneans. Since the morphology of sclerites of the attachment organ (haptor) is one of the primary criteria in tetraonchid taxonomy, the confocal study of sclerites and associated musculature may provide valuable taxonomic information. The aim of this study was to examine the haptoral sclerites and musculature in Tetraonchus monenteron (Wagener, 1857), a common parasite of pike. Haptoral musculature of T. monenteron was studied using phalloidin staining and confocal microscopy, with sclerites visualized in the reflection confocal mode. Haptoral armature of T. monenteron consists of ventral and dorsal pairs of anchors, a ventral bar, eight pairs of marginal hooks and at least three pairs of accessory sclerites. Anchors are operated by 14 muscles, of which the most prominent are extrinsic muscles, the transverse muscle interconnecting the ventral anchors, three muscles connecting the ventral anchor to the ventral bar, and four muscles of the dorsal and ventral anchors inserting on the haptoral wall. The extrinsic muscles are attached to the braceshaped sclerites, which in turn are connected to the dorsal anchors via muscle bundles. The gaffing action of the dorsal anchors is likely to be achieved by the extrinsic muscles and the transverse muscle that clamps the extrinsic muscles against the body wall. The ventral anchors are probably held in attached position by the transverse muscle and four muscles inserting on the ventral bar and haptoral wall. The haptoral musculature may have potential utility for tetraonchid taxonomy. [ABSTRACT FROM AUTHOR]

Dendrobaena veneta is one of the most widely used compost worms now distributed all over Europe and has been described under several synonymous names. Besides the typical stripy red specimens, another form bearing pinkish pigmentation also exists, mostly found in natural habitats in the East Mediterranean. Here we provide the first integrative taxonomic analysis of D. veneta, including some closely related species. Both the morphological and molecular results highly support the resurrection of D. succinta, a former synonym of D. veneta. In addition, we describe a peculiar new species, D. karacadagi sp. n. from Anatolia, and prove the highly homoplasious character of the cross section of the longitudinal musculature. [ABSTRACT FROM AUTHOR]

Highlights • Wormlions, pit-building predatory larvae, occur in high densities in urban habitats. • They are also bigger in cities than natural habitats and construct larger traps. • Urban habitats are richer with small ants that may serve as prey. • Urban habitats also have more space available for pit construction. • Wormlions are probably pre-adapted to living in urban habitats. Abstract Wormlions are fly larvae that construct pit-traps in loose soil and ambush prey that fall into their pits. They occur in high numbers in cities, below any man-made shelter providing protection from direct sunlight, such as a concrete roof with a thin layer of sand at the ground. Their natural habitat is either caves or any natural structure that provides full shade. We characterized a large urban habitat and compared it to two natural habitats, where wormlions occur in caves. Wormlions were abundant in all studied habitats. Our goals were to understand whether wormlions in the urban habitat perform better than in the natural habitats, and to suggest differences between the habitats that may contribute to their success under man-made shelters. Wormlions in the city reached larger size before pupation, and wormlion clusters there were larger. The studied urban habitat contained more concrete and perennial plants, while the natural habitats comprised of more annuals. We suggest that this concrete, covered with a thin layer of sand, leads to large areas suitable for wormlions. Furthermore, ants were more common in the urban habitat than the natural habitats, referring to their relative proportion of all arthropods collected. We suggest that these small ants provide suitable prey for wormlions, especially in the early stages of their development, when wormlions are limited by prey size. This could explain why they reach larger size prior to pupation. Pits were probably larger because they were constructed by larger individuals. In conclusion, we suggest that wormlions present an interesting case of an insect pre-adapted to urban life. [ABSTRACT FROM AUTHOR]

Most subsoil carbon (C) turnover occurs in biopore hotspots such as root channels and earthworm burrows. Biopores allocate large C amounts into the subsoil, where a vast capacity for long-term C sequestration is predicted. We hypothesise that organic matter (OM) cycling in biopores depends on their origin. Earthworm and root biopores were induced under field conditions and were sampled from the subsoil (45–75 and 75–105 cm) after two years of biopore formation. The effects of biopore formation on OM decomposition were studied by biomarkers: neutral sugars, cutin and suberin-derived lipids, lignin-derived phenols and free lipids. The degradation stage of OM was biopore type-specific but was only governed by the soil depth in root biopores. Degradation of OM increased from earthworm biopores to root biopores and bulk soil. Hemicelluloses (GM/AX ratio) were more strongly degraded than lignin side-chains (relative change from initial values). Two years of microbial processing during biopore formation increased the GM/AX ratio in earthworm biopores from 0.65 to 1.05 and in root biopores from 0.15 to 1.35 (both relative to source biomasses). Root biopores and bulk soil had the highest GM/AX ratios (1.2–1.3), hinting to rapid processing of plant residues and accumulation of microbial residues. The regular, frequent OM inputs by earthworms stimulated microbial growth and processing of mostly bioavailable OM and, thus, relatively enriched more persistent OM (e.g. lignin). Syringyl subunits of lignin underwent low (ratio changed from 0.35 to 0.55 relative to initial input) and vanillyl subunits underwent almost no processing in earthworm biopores indicating the preferential microbial utilisation of the easily available compounds frequently replenished by earthworm activity. After two years of decomposition of the root detritus, mainly structural plant material was enriched in root biopores. Short periods (6 months) of earthworm activity effectively recharged the highly processed OM in root biopores with fresh OM. In total, deep-rooting catch crops and short-term earthworm activities promote C accumulation in the subsoil followed by biopore-specific microbial processing predominantly governed by the C input frequency. As root biopores are up to 40 times more common than earthworm biopores, they dominate the OM input into subsoils. Such C inputs create several years lasting hotspots for preferential root growth and nutrient mobilisation in the subsoil. We conclude that root- and earthworm-derived biopores are vertical pathways for plant C from the soil surface into the subsoil and for intensive processing of litter C and sequestration of microbial necromass. [ABSTRACT FROM AUTHOR]

This comprehensive study was undertaken to reveal the ovarian histomorphology in the oligochaetous clitellte, Dendrobaena atheca Cernosvitov. Efforts were, in fact, made to obtain proper histological preparations. So, various types of thin serial sections of ovaries were carefully obtained, stained and examined. Two small ovaries, at the beginning of breeding seasons, were seen in segment thirteen. Subsequently, they extremely increased in size and became fully formed. They demonstrated six principal cell types: peritoneal cell, follicular cell, stromal cell, oogonium, oocyte and trophocyte (nurse cell). The first three cell types were somatic, whereas the other three were germ and germ-line. All cell types were, as much as possible, properly described. Dividing oogonia were seen to produce oocytes and trophocytes simultaneously. The produced cells were seen to be interconnected. The stromal cell, a newly described cell type, exhibited several specific cell characteristics. Ovaries showed no internal lumens. The small ovaries showed only two distinct histological zones, whereas the large ones showed three such zones. Germ and germ-line cells showed an obvious arrangement in ovarian zones. Accordingly, the chief conclusions are: (1) ovaries are nutrimental due to presence of trophocytes (2) ovaries are solid and not sac-like organs due the lack of internal cavity (3) stromal cell can be considered a new cell type as it demonstrates several specific cell features (4) Ovarian zonation is caused by production and arrangement of germ and germ-line cells (5) intercellular connections are due to incomplete cell divisions. [ABSTRACT FROM AUTHOR]

Information on the bioaccumulation of selenium (Se) in soil invertebrates (e.g. earthworms) is rather scarce. In the present study, bioaccumulation of Se in two eco-physiologically different earthworms, namely anecic Pheretima guillemi and epigeic Eisenia fetida , was determined after 28 days exposure to a successive doses of Se-spiked soil, specifically 0.5, 5, 50, and 200 μg Se g −1 soil. The results showed that Se concentration in earthworms elevated with increasing exposure levels, and maximums were up to 54.6 and 83.0 μg g −1 dry weight in Pheretima guillemi and Eisenia fetida , respectively, after 4 weeks exposure to 200 μg Se g −1 soil. Exposure to Se caused significant inhibition on earthworm growth, with the fresh weight loss ranging from 8.9% to 80.5%. Bioaccumulation factors (BAFs), empirically-derived and non-steady state, ranged from 0.12 to 4.17 and generally declined at higher exposure levels. Moreover, BAFs of Pheretima guillemi were higher than those of Eisenia fetida in low-dose Se-spiked soils, but the opposite was true in high-dose soils, indicating there is a species-specific response to exposure of Se between different earthworms. Further research is thus needed to reveal the accumulation pattern of Se in a wider range of earthworm species other than Eisenia fetida , which allows a better risk assessment of excessive Se to soil invertebrates and higher order organisms. [ABSTRACT FROM AUTHOR]

Earthworms play a key role in soil and ecosystem functioning. Predicting their abundance and spatial distribution is required to understand their ecological role. There is growing evidence that mechanistic models of earthworm population dynamics are promising tools to tackle this issue. However, this approach requires a fair amount of data because it explicitly integrates the three fundamental biological processes: growth, reproduction and mortality. Hitherto, the lack of comprehensive databases on life history parameters related to these three processes hampered the widespread development of mechanistic earthworm population dynamics models. As a consequence, predicting earthworm abundance in a variety of conditions across species is still difficult. The clear bottleneck for making progress is the lack of databases on the intraspecific variability of earthworm life history traits in response to environmental conditions. Data related to body growth and body size are critical because body size largely determines reproduction and mortality rates. Body growth is therefore the backbone of mechanistic models of earthworm population dynamics. Here I present EGrowth, the first comprehensive database on intraspecific variability of earthworm body growth in relation to environmental conditions. The EGrowth database contains 1073 growth curves of 51 species of earthworms, representing 16002 measures of body mass. It covers publications on earthworm body size from 1900 to 2016. The environmental conditions in which the growth curves were produced are also reported. The database is open access and can be browsed from a graphical user interface. EGrowth will be updated regularly in the future as new studies are published. I propose a standardized framework for reporting future data on body growth of earthworms. [ABSTRACT FROM AUTHOR]

The evolution of eyes and their constituent photoreceptor cells in Metazoa in general and in Protostomia in particular remains unresolved with present morphological and developmental genetic data. This is mainly due to the lack of comprehensive ultrastructural data in some lineages, such as in the spiralian taxon Nemertea. The eyes of the derived Neonemertea possess rhabdomeric photoreceptor cells, considered typical of the protostome lineage. In the more basally branching palaeonemertean lineages, ultrastructural data on the eyes are wanting. Ultrastructural investigation of the eyes of the larva of the palaeonemertean Procephalothrix oestrymnicus reveals that, although in a similar position as the eyes of adult neonemertean species, the eyes in palaeonemertean larvae differ fundamentally from the expected protostomian type: They consist of one shading-pigment cell that forms a closed optical cavity embedded in the epidermis. Apart from basally distributed shading-pigment vesicles, the pigment cell apically possesses epidermal cilia and microvilli as well as sub-apical, tubular lens vesicles. Two ciliary photoreceptor cells project flattened ciliary membranes into the optical cavity formed by the pigment cell, whereas their basal portions are situated outside of the optical cavity, next to the shading-pigment cell. Although the structure of the eye in P. oestrymnicus is unparalleled in Nemertea, ciliary photoreceptor cells have been found in larval eyes of several other spiralian lineages. Occurrence of additional ciliary-type eyes in Spiralia deepens the doubts regarding the validity of the hypothesis of an exclusively rhabdomeric line of visual photoreceptor cell evolution in Protostomia. [ABSTRACT FROM AUTHOR]

This study has determined the relationship of culturable community of cellulose degrading bacteria (CDB) within the gut walls of two habitat-specific earthworm species, epigeic (compost heap inhabitant) earthworm, Perionyx excavatus (PE) and an endogeic (submerged rice field inhabitant), Glyphidrilus spelaeotes (GS) and their functional significance. The 16Sr RNA analysis for the isolated CDB from two ecologically distinct earthworms clearly showed the presence of distinct communities of CDB in their gut ecosystem. Enzymatic assay of cellulase for the isolated CDB showed significantly higher cellulase activity compared to the reference strain M-23, Cellulomonas cellulans (P < 0.01, one-way ANOVA). The functional significance of such high cellulase activity was also demonstrated by the enhancement of decomposition of rice straw and fresh vegetation biomass in the presence of native microbiota community. The growth rate of CDB of epigeic PE was approximately twice slower than that of CDBs of endogeic GS. The CDB of PE exhibited 12 polymorphs of esterase isozyme as against 4 polymorphs for CDB of GS. The present study emphasizes the functionally significant relationship of gut wall CDB and host earthworm for sustaining efficient C-cycling in agroecosystems. [ABSTRACT FROM AUTHOR]

Adult and cystacanth forms of the acanthocephalan Serrasentis sagittifer from Australian coastal waters are redescribed and verified as the same species using both molecular and morphological data. This study provides the baseline 18S rDNA, 28S rDNA, and cox1 sequence data to serve as genetic barcode for S. sagittifer. The validity of the currently recognized species of Serrasentis is discussed. The most recently described species are junior synonyms of either Serrasentis nadakali or S. sagittifer, and a number of species are species inquirenda. When using morphological characters to distinguish the species of Serrasentis, consideration needs to be given to the maturity of the specimens, since the trunk elongates and the number and distribution of the ventral combs changes as worms mature, although the proboscis armature itself does not change. A simple key to assist in the identification of species of Serrasentis is provided. Adult S. sagittifer appear to be highly host specific to the cobia, Rachycentron canadum, in northern Australian waters, whereas cystacanths have been reported from a wide range of fish species. The relationship between host length and number of cystacanths shows that most paratenic infections are acquired as young fish, most likely via a crustacean intermediate host. [ABSTRACT FROM AUTHOR]

Mitochondrial cytochrome oxidase subunit I (COI) and 16S rRNA gene sequence data were analysed for 43 specimens of Drawida ghilarovi – earthworms of a tropical genus on the northern boundary of their natural habitat, including two ecological forms and three colour morphs collected from different regions of the southern Russian Far East. Intraspecific genetic differentiation of these clitellata was analysed with different criteria that characterise different forms and morphs. A sample of anecic worms was shown to possess higher genetic variation than a sample of epigeic worms. Haplotype network reconstructions showed that the meadow-swamp epigeic black-coloured D. ghilarovi is more highly diverged from the anecic forest grey- and brown-coloured worms than the grey and brown colour morphs are from each other. Genetic differentiation between three colour morphs ranged from 9.89 ± 0.58 to 11 ± 0.59% using COI and 16S data. An AMOVA test and an exact test showed a high probability of non-differentiation between grey and brown earthworms. A multimodal mismatch distribution was revealed for the whole D. ghilarovi sample and for each colour morph. The minimum spanning tree showed that the differentiation of specimens is associated with ecological and geographical criteria. Molecular data for Drawida showed high genetic differentiation between epigeic and anecic using COI and 16S gene sequence data as well as the various phylogenetic relationships among the studied forms. The anecic earthworms possibly represent different genetic lineages of the D. ghilarovi species complex. The epigeic Drawida , based on the complex data, can be considered a new species of this genus. [ABSTRACT FROM AUTHOR]

Bioaccumulation factors for heavy metals (Cd, Zn, Cu, and Pb) were examined for selected earthworm species ( Metaphire californica, Amynthas homochaetus, Amynthas pecteniferus , and Amynthas heterochaetus ) that inhabit metal-polluted soils in a subtropical area (Hunan Province) of South China. The earthworms had high plasticity in inhabiting in situ contaminated areas and showed high uptake of the heavy metals and capability for their accumulation in the tissues. The bioaccumulation factor (BAF) were greatest for cadmium and ranked as follows: Cd (10.6–18.8) >> Zn (1.15–1.75) > Cu (1.01–1.35) > Pb (0.56–0.95). Earthworm species with the similar BAF of heavy metals ( p > 0.05) belong to the same ecological group. Within individual groups, Cd, Cu, Zn, Cu, and Pb concentrations in earthworms are consistently predicted by total and extractable fraction (DTPA-extractable) in soil. Our results provide insights into the ecological relationships and variations in the uptake and accumulation of heavy metals in different earthworm species in contaminated soils in China. [ABSTRACT FROM AUTHOR]

Copper oxide nanoparticles and copper sulfate are established contaminants of water and soil. Metaphire posthuma is a common variety of earthworm distributed in moist soil of Indian subcontinent. Comparative toxicity of copper nanoparticles and copper sulfate were investigated with reference to selected immune associated parameters of earthworm. Total count, phagocytic response, generation of cytotoxic molecules (superoxide anion, nitric oxide), activities of enzymes like phenoloxidase, superoxide dismutase, catalase, acid phosphatase, alkaline phosphatase and total protein of coelomocytes were estimated under the exposures of 100, 500, 1000 mg of copper oxide nanoparticles and copper sulfate per kg of soil for 7 and 14 d. A significant decrease in the total coelomocyte count were recorded with maximum depletion as 15.45 ± 2.2 and 12.5 ± 2 × 10 4 cells/ml under the treatment of 1000 mg/kg of copper nanoparticles and copper sulfate for 14 d respectively. A significant decrease in generation of nitric oxide and activity of phenoloxidase were recorded upon exposure of both toxins for 7 and 14 d indicating possible decline in cytotoxic status of the organism. A maximum inhibition of superoxide dismutase activity was recorded as 0.083 ± 0.0039 and 0.055 ± 0.0057 unit/mg protein/minute against 1000 mg/kg of copper nanoparticles and copper sulfate treatment for 14 d respectively. Activities of catalase and alkaline phosphatase were inhibited by all experimental concentrations of both toxins in the coelomocytes of earthworm. These toxins were recorded to be modifiers of the major immune associated parameters of M. posthuma. Unrestricted contamination of soil by sulfate and oxide nanoparticles of copper may lead to an undesirable shift in the innate immunological status of earthworm leading to a condition of immune compromisation and shrinkage in population density of this species in its natural habitat. This article is the first time report of immunological toxicity of nanoparticles and sulfate salt of copper in M.posthuma inhabiting the soil of India, an agriculture based country. [ABSTRACT FROM AUTHOR]

Introduction: The earthworm coelomic fluid (ECF) has shown proven antiproliferative effect against breast, liver, gastrointestinal and brain cancer, but it is least explored in oral cancer. The present in vitro study is an attempt to investigate the antiproliferative activity of ECF on oral cancer cell line squamous cell carcinoma (SCC)-9. Materials and Methods: ECF was collected from the species Eudrilus eugeniae (EE), Eisenia foetida (EF) and Perionyx excavatus (PE) stored at -80°C. Percentage inhibition of ECF on squamous cell carcinoma-9 cells in vitro was recorded at 24 h. Protein estimation was done using Bradford protein assay validated by the biuret method. Cytotoxicity was tested at 2.5, 5, 10, 20, 40 and 80 μg/ml concentrations by 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay in SCC-9 cells in vitro. GraphPad Prism 7.0 software was used to calculate the inhibitory concentration (IC50). Chi-square test was used to analyze the difference between samples. Results: The test samples EE, EF and PE inhibited the growth of SCC-9 cells significantly in a dose-dependent manner and the IC50 values were found to be 4.6, 44.69 and 5.27 μg/ml, respectively. The antiproliferative effect was found to be variable among the three earthworm species with EE showing the most promising effect followed by PE and EF. Conclusion: Establishing the antiproliferative effect of ECF on oral cancer cells could be an initial step toward drug development and future anticancer research. The preliminary investigation has shown that ECF has a promising antiproliferative effect on oral cancer cells in vitro. [ABSTRACT FROM AUTHOR]

The intent of this paper was to give an overview of the distribution of the earthworm taxa across the ecoregions of continental USA and Alaska. It contains a descriptive summary of each of the 104 ecoregions and the citation of 81 papers each giving a more detailed description of the earthworm taxa including the number of families, genera and species recorded in each. The 81 ecoregion papers include 10 families, 43 genera and 191 species. Additionally, there is a summary table of the taxa in the American Ecoregions and an Appendix Table of collections or records, omitted or received after the individual ecoregions were published. There are colour maps of the Continental Ecoregions, the Alaskan Ecoregions, and the Hawaiian Ecoregions. [ABSTRACT FROM AUTHOR]

The objective of the study consisted in determining some biologically active properties of the pheromone of anxiety(secret), obtained from the tissues of the Red Hybrid Worm of California for the purpose of its use in veterinary medicine. The object of the research served: the Red Hybrid worm of California, the pheromone of anxiety both natively and in various dilutions (from 1:1 to 1:100). During the study, the following methods were used: to obtain the pheromone of anxiety and sterilizing of it; the determination of bactericidal activity and lysozyme was performed by the photonefelometry method. As a result of the research it was found that the pheromone of anxiety manifested bactericidal activity towards microbial cultures Staphylococcus aureus (° 209), Escherichia coli, Micrococcus luteus (Micrococcus lysodeikticus), Candida albicans depending on the used dilutions. In the undiluted native secret, the bactiricidal activity, tested by using these crops, constituted respectively 552.00%, 355.00% and 13,500.00%, and in the dilutions 1:1 - 1:100 it oscillated respectively from 250.00%, 370.00% and 3,900.00% till 23.00%, 42.00% and 100.0%. Towards the microbian culture Candida albicans microbial activity was not found. The lysozyme activity of the undiluted pheromone of anxiety constituted 10.20%, and in the dilutions 1:10 - 1:100 it oscillated from 8.60% to 8.70%, which led to the fact that research would no longer be continued. Thus, it was found that the pheromone of anxiety, obtained from tissues of Red Hybrid worm of California, has manifested a bactericidal activity depending on the concentration and type of microbial cultures on which the test was performed. [ABSTRACT FROM AUTHOR]

Earthworm collecting trips to different parts of Austria - the Karawanks, Carinthia, Lower and Western Austria - resulted in recording altogether 17 species. Based on the morphological data, Dendrobaena velkovrhia Mršić, 1988 is found to be a synonym of Dendrobaena auriculifera Zicsi, 1969. The problems with the previously published Eisenia lucens (Waga, 1857) records and these specimens’ supposed identity with E. spelaea (Rosa, 1901) are also discussed. [ABSTRACT FROM AUTHOR]

Species with multiple different larval developmental modes are interesting models for the study of mechanisms underlying developmental mode transitions and life history evolution. Pygospio elegans, a small, tube-dwelling polychaete worm commonly found in estuarine and marine habitats around the northern hemisphere, is one species with variable developmental modes. To provide new genomic resources for studying P. elegans and to address the differences in gene expression between individuals producing offspring with different larval developmental modes, we performed whole transcriptome Illumina RNA sequencing of adult worms from two populations and prepared a de novo assembly of the P. elegans transcriptome. The transcriptome comprises 66,233 unigenes, of which 33,807 contain predicted coding sequences, 26,448 have at least one functional annotation, and 3,076 are classified as putative long non-coding RNAs. We found more than 8,000 unigenes significantly differentially expressed between adult worms from populations producing either planktonic or benthic larvae. This comprehensive transcriptome resource for P. elegans adds to the available genomic data for annelids and can be used to uncover mechanisms allowing developmental variation in this and potentially other marine invertebrate species. [ABSTRACT FROM AUTHOR]

Taxonomic studies on scolopendrid centipedes have often documented variability at the individual and population levels and applied those data to questions of species delimitation, but these investigations have mostly lacked an explicit phylogenetic framework. A molecular phylogeny and recent taxonomic revision for Indian species of the scolopendrid Digitipes Attems, 1930, permit variability of traditional taxonomic characters for Scolopendridae to be mapped onto a phylogeny. Based on their fit to the tree using maximum likelihood, reliable species-level characters include the number of glabrous antennal articles, presence of a median ridge on the tergites, and presence or absence of a tarsal spur on leg 20. Characters that are conserved within and diagnostic for particular species but labile within others (typically with geographic structure) include the first tergite with paramedian sutures, presence or absence of a lateral spine on the coxopleuron, and the number of spines in a ventromedial row on the ultimate leg prefemur. Comparisons with published accounts of variability in species of other scolopendrid genera, particularly Scolopendra and Otostigmus, show that Indian Digitipes has conserved morphology in some characters that are taxonomically useful elsewhere in the family, and most of its taxonomically informative characters have analogous patterns of variability in other genera. The approach used in this study to evaluate morphological variation in a phylogenetic framework can be applied to other taxa in which morphologically cryptic species have been reported and where species diagnosis requires a combination of characters. [ABSTRACT FROM AUTHOR]

The application of herbicides in agricultural practices may pose certain toxic effects on non-target species including molluscs (snails), earthworms and other soil-dwelling organisms, which would in turn put the lives of humans at great risk. This study considered the lethal and sublethal effects of Grassate®, a non-selective glyphosate-based herbicide on snails (Archachatina marginata) and earthworms (Aporrectodea longa) with regards to ecotoxicological risk assessment. The lethal concentration LC50for the test chemical averaged at 1.731 ± 0.05 and 3.045 ± 0.08 mg kg−1for snails and earthworms, respectively. There was decrease in growth and biomass with increased concentration for the species. Growth inhibition of 11–38% in size and 7–43% in length was obtained for earthworms while 26–65% reduction in weight was reported for snails. Using the ecotoxicological risk assessment matrix, the herbicide was classified as D 4 (A; P; E) or 16 (A; P; E), which could be considered as high risk to animals, plant and the environment. Thus, if these herbicides are used uncontrollably and unregulated, further consequence could lead to harmful effects on humans who feed on snails, a rich source of protein and depend on earthworms for nutrient. [ABSTRACT FROM PUBLISHER]

Background: Earthworms (Crassiclitellata) are a diverse group of annelids of substantial ecological and economic importance. Earthworms are primarily terrestrial infaunal animals, and as such are probably rather poor natural dispersers. Therefore, the near global distribution of earthworms reflects an old and likely complex evolutionary history. Despite a long-standing interest in Crassiclitellata, relationships among and within major clades remain unresolved. Methods: In this study, we evaluate crassiclitellate phylogenetic relationships using 38 new transcriptomes in combination with publicly available transcriptome data. Our data include representatives of nearly all extant earthworm families and a representative of Moniligastridae, another terrestrial annelid group thought to be closely related to Crassiclitellata. We use a series of differentially filtered data matrices and analyses to examine the effects of data partitioning, missing data, compositional and branch-length heterogeneity, and outgroup inclusion. Results and discussion: We recover a consistent, strongly supported ingroup topology irrespective of differences in methodology. The topology supports two major earthworm clades, each of which consists of a Northern Hemisphere subclade and a Southern Hemisphere subclade. Divergence time analysis results are concordant with the hypothesis that these north-south splits are the result of the breakup of the supercontinent Pangaea. Conclusions: These results support several recently proposed revisions to the classical understanding of earthworm phylogeny, reveal two major clades that seem to reflect Pangaean distributions, and raise new questions about earthworm evolutionary relationships. [ABSTRACT FROM AUTHOR]

A new species of the ampharetid genus Phyllocomus, P. chinensis sp. n., is described based on material from the Yellow Sea. The new species is distinguished from the known species of this genus by having two thoracic regions, with segments of the anterior region (up to thoracic chaetiger 10) approximately half as long as those of the posterior region, neuropodia of the anterior region are large while those of the posterior region become gradually smaller, thoracic neuropodia without dorsal cirrus, and abdominal neuropodia with a papillary dorsal cirrus. A key to all species of Phyllocomus is given. [ABSTRACT FROM AUTHOR]

Partitioning tissue metal concentration into subcellular compartments reflecting toxicologically available pools may provide good descriptors of the toxicological effects of metals on organisms. Here we investigated the relationships between internal compartmentalization of Cd, Pb and Zn and biomarker responses in a model soil organism: the earthworm. The aim of this study was to identify metal fractions reflecting the toxic pressure in an endogeic, naturally occurring earthworm species (Aporrectodea caliginosa) exposed to realistic field-contaminated soils.After a 21 days exposure experiment to 31 field-contaminated soils, Cd, Pb and Zn concentrations in earthworms and in three subcellular fractions (cytosol, debris and granules) were quantified. Different biomarkers were measured: the expression of a metallothionein gene (mt), the activity of catalase (CAT) and of glutathione-s-transferase (GST), and the protein, lipid and glycogen reserves. Biomarkers were further combined into an integrated biomarker index (IBR).The subcellular fractionation provided better predictors of biomarkers than the total internal contents hence supporting its use when assessing toxicological bioavailability of metals to earthworms. The most soluble internal pools of metals were not always the best predictors of biomarker responses. metallothionein expression responded to increasing concentrations of Cd in the insoluble fraction (debris + granules). Protein and glycogen contents were also mainly related to Cd and Pb in the insoluble fraction. On the other hand, GST activity was better explained by Pb in the cytosolic fraction. CAT activity and lipid contents variations were not related to metal subcellular distribution. The IBR was best explained by both soluble and insoluble fractions of Pb and Cd.This study further extends the scope of mt expression as a robust and specific biomarker in an ecologically representative earthworm species exposed to field-contaminated soils. The genetic lineage of the individuals, assessed by DNA barcoding with cytochrome c oxidase subunit I, did not influence mt expression. [ABSTRACT FROM AUTHOR]

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

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The morphology of the jaw apparatus of Mooreonuphis stigmatis was studied at different stages of development using light and electron microscopy as well as 3D reconstruction techniques. Three generations of maxillary apparatuses were identified. The first (larval) type of maxillae was found in juveniles that have from 4 up to 15 chaetigers. They are formed by short microvilli and have no capacity for continuous growth, as they are completely replaced by the subsequent generation of jaws. The second (juvenile) type of maxillae appears in individuals that have from 10 to 18 chaetigers. They are fully penetrated by long microvilli and have a layer of collagen fibrils in the basicuticle. The third (adult) type of maxillae is found in worms that have at least 92 chaetigers. These maxillae have long microvilli that penetrate the intermediate layer of the basicuticle but do not reach the thick collagen layer. The mandibles and two generations of maxillae (adult and juvenile) have the capacity for continuous growth. Previously, it was thought that different types of jaw structures are characteristic of different annelid taxa (for example, Dorvilleidae, Adercodon , etc.). Our data suggest that all three types of structures are found during developmental changes of the jaws in one species. The similarity between the larval maxillae of M. stigmatis and maxillary apparatus of Dorvilleidae supports the progenetic origin of the latter. The features of fine morphology suggest that the larval maxillae of Onuphidae have more chances to be fossilized than the adult maxillae. Consequently, the larval maxillae of labidognath Eunicida could be better represented in fossil material, while the calcified adult maxillae have a lower preservation capacity. [ABSTRACT FROM AUTHOR]

Root-knot nematodes, Meloidogyne spp., cause huge economic losses worldwide. Currently, three Meloidogyne spp. are present on the quarantine A2 list of EPPO, M. chitwoodi, M. fallax and M. enterolobii. As a quarantine organism, M. fallax has been detected in England and Northern Ireland on sport turf in 2011, and in England on leek in 2013. However, its presence in Ireland has probably been overlooked since 1965, when Mr. John F. Moore and Dr. Mary T. Franklin had detected a new Meloidogyne species for that time. While the relevant data was recorded and a preliminary manuscript describing the species was prepared but never submitted for publication, and together with the original slides, pictures and drawings, it was restudied recently. We compared the population of Irish Meloidogyne sp. to other similar Meloidogyne spp. Careful observation and comparison shows that it belongs to M. fallax. The characters found to be common for Irish Meloidogyne sp. and M. fallax are female stylet length (14.6 μm) with oval to rounded basal knobs, oval shaped perineal pattern with moderately high dorsal arch, slender stylet in males (18.5 μm) with set off and rounded basal knobs, slightly set off male head with one post-labial annule and incomplete transverse incisures, and second-stage juveniles with large and rounded stylet basal knobs, and a gradually tapering tail (46.9 μm) with a broadly rounded tip and a clearly delimitated smooth hyaline part sometimes marked by constrictions (12.9 μm). The host test and gall formation also correspond to M. fallax. The identification could not be additionally supported by molecular analysis, as we were unable to extract DNA from the old permanent slides. Nevertheless, our study reveals that the Meloidogyne species detected in Ireland in 1965 belongs to M. fallax. [ABSTRACT FROM AUTHOR]

Comparative studies on the efficacy of methanolic extracts of (Punicagranatum) and triclabendazoal on Haemonchusspp by using scanning electron microscope (SEM) revealed that, Punicagranatum and ACBZ showed significant effect on adult worms of Heamonchuscontortousafter 24h in vitro cultivation, the worms started to stop motion animation and paralysis leading 100 % to death of worms. Adult H. contortus: Scanning electron microscopy (SEM) of normal fresh worms showed, the mouth of the normal fresh worm was hexagonal with six semicircular rudimentary lips, lateral amphids, papillae and dorsal buccal lancet. The later was a specialized cuticular structure arising from the cuticular lining of the dorsal wall of the buccal cavity. The lancet's anterior tip and lateral edges were slightly rounded. A pair of cervical papillae was prominent and spine-like. The cuticle was transversally striated and with lateral ridges. SEM of Treated WormsH. contortusafter 24 h incubation with 50 mg/ml ethanolic extracts of Punicagranatumpeelshowed the buccal capsule which presented a smooth surface in control worm, lost their normal aspect and showed distortion with severe blebbing of the lips. The cuticle including the lips appeared to be more swollen than normal The transverse striations became less pronounced and lost their normal aspect showing longitudinal wrinkles. The treated worms showed distortion of both buccal capsule and cuticle. The lips were deformed and the cuticular surface had a wrinkled, corrugated appearance. Besides, longitudinal thickening and wrinkling of the cuticular ridges were observed. [ABSTRACT FROM AUTHOR]

Linopherus beibuwanensis sp. n. is described based on six specimens deposited in the Marine Biological Museum of the Chinese Academy of Sciences, Qingdao, collected from the Beibu Gulf (Tokin Gulf ), South China Sea. The new species differs from all other Linopherus species by the shape of prostomium and caruncle. The posterior margin of prostomium is bilobed; the caruncle arises medially and confluently from the posterior margin of the prostomium, joining together with prostomium. A key to distinguish the known species of the genus is provided. [ABSTRACT FROM AUTHOR]

The Central Great Plains Ecoregion in the United States occurs in a portion of four states in the American mid-west (Kansas, Nebraska, Oklahoma and Texas). There are 25 species and one subspecies found here, representing seven genera and three families (Acanthodrilidae, Lumbricidae and Megascolecidae). Eighteen of the species are native (endemic) to North America; all are European or Oriental (exotic) introductions. A description of the ecoregion and five colour photographs are also included. [ABSTRACT FROM AUTHOR]

The Western Corn Belt Plains Ecoregion in the United States occurs in a portion ofseven states in the American midwest. There are 26 species found here, representing 12 genera and four family (Acanthodrilidae, Lumbricidae, Megascolecidae and Sparganophilidae). Twelve of the species are native (endemic) to North America; all are European or Oriental (exotic) introductions. A description of the ecoregion and eight colour photographs are also included. [ABSTRACT FROM AUTHOR]

A total of 20 species of earthworms belonging to 13 genera and five families are recorded from northern Indian state of Haryana. Among them, five new records of Ocnerodrilus occidentalis Eisen, Lennogaster pusillus (Stephenson), Ramiella bishambari (Stephenson), Metaphire houlleti (Perrier) and Metaphire birmanica (Rosa) are reported. A simple key for the identification of earthworms of the area is provided. [ABSTRACT FROM AUTHOR]

The Cross Timbers Ecoregion in the United States occurs in portions ofthree states in the American central region (Kansas, Oklahoma and Texas). There are 17 species found here, representing eight genera and four families (Acanthodrilidae, Lumbricidae, Megascolecidae, Sparganophilidae). Thirteen of the species are native (endemic) to North America; all are European or Oriental (exotic) introductions. A description of six ecoregion and three colour photographs are also included. [ABSTRACT FROM AUTHOR]

The Flint Hills Ecoregion in the United States occurs in portions of two states (Kansas and Oklahoma). There are 17 species found here, representing five genera and three families (Acanthodrilidae, Lumbricidae and Megascolecidae). Twelve of the species are considered native (endemic) to North America; all others are European or Oriental introductions (exotics). A description of the ecoregion and five colour photographs are also included. [ABSTRACT FROM AUTHOR]

Velvet worms, "peripatus" or onychophorans, are "living fossils" that were geographically widespread in Cambrian seas but now occur exclusively on terrestrial habitats. The only extant species studied in some detail are those from Costa Rica, but their real geographic distribution was in urgent need of revision. To solve this problem we visited the localities mentioned in all the original taxonomic descriptions and redescriptions. These visits covered a 25 year period (1988-2014) and included interviews with local residents. We also examined all Costa Rican collections, and checked the information in old maps and books. Here we critically review geographic data, correct errors, assign neotype localities, report on the survival of populations after heavy volcanic eruptions or urbanization, and present the correct geographical distribution for the seven currently described Costa Rican species. [ABSTRACT FROM AUTHOR]

The Acanthocephala is a phylum of obligate endoparasitic animals comprising four classes ( Archiacanthocephala, Palaeacanthocephala, Eoacanthocephala and Polyacanthocephala), although the phylogenetic interrelationships of these classes still remains unresolved. To investigate phylogenetic relationships of major acanthocephalan groups, we characterized the complete mitochondrial genome sequences of two palaeacanthocephalan species Centrorhynchus aluconis and Prosthorhynchus transversus (representing two different families of the order Polymorphida), and Polyacanthorhynchus caballeroi (the first mitogenomic representative of the class Polyacanthocephala) and used these new sequences for phylogenetic analyses, along with 32 platyzoan mt DNAs, including 10 additional acanthocephalans. Phylogenetic analyses using concatenated amino acid sequences for 12 protein-coding genes with maximum likelihood and Bayesian inference methods supported monophyly of Acanthocephala. Within the phylum, Archiacanthocephala was positioned as the sister to the clade containing all three other acanthocephalan classes, with the polyacanthocephalan species P. caballeroi nested within Eoacanthocephala. This result contradicts morphology-based classification systems that treated polyacanthorhynchids as one of the palaeacanthocephalan families, and instead suggests Polyacanthocephala is a member of Eoacanthocephala. Within the Palaeacanthocephala, Polymorphida monophyly was strongly supported and this is inconsistent with nuclear r DNA-based molecular hypotheses that suggest non-monophyly. [ABSTRACT FROM AUTHOR]

A new species, Araguanema mutabile sp. nov., from the coelomic cavity of a glossoscolecid earthworm Aptodrilus fuhrmanni Michaelsen, 1918 deposited in the collection of Natural History Museum of Geneva, is described and illustrated. The new species is characterised by the presence of two types of somatic sensory organs, i.e. vesicular and fimbriate, four cephalic papillae, a small cuticularised stoma, a muscular, clavate pharynx, a nerve ring encircling isthmus, no distinct spermatheca, and a posterior position of vulva and thick-shelled eggs. From the only known species of the genus, A. venezuelae Ivanova & Hope, 2004, it differs by the differently shaped pharynx, indistinct vs distinct amphids, a stoma with cuticularised vs non-cuticularised walls, the different arrangement of the sensory organs, and more numerous eggs with ornamented vs smooth egg-shells. The significance of the number of somatic organs for the species identification is discussed. [ABSTRACT FROM AUTHOR]

The excretory system of the nematode Caenorhabditis elegans is a superb model of tubular organogenesis involving a minimum of cells. The system consists of just three unicellular tubes (canal, duct, and pore), a secretory gland, and two associated neurons. Just as in more complex organs, cells of the excretory system must first adopt specific identities and then coordinate diverse processes to form tubes of appropriate topology, shape, connectivity, and physiological function. The unicellular topology of excretory tubes, their varied and sometimes complex shapes, and the dynamic reprogramming of cell identity and remodeling of tube connectivity that occur during larval development are particularly fascinating features of this organ. The physiological roles of the excretory system in osmoregulation and other aspects of the animal's life cycle are only beginning to be explored. The cellular mechanisms and molecular pathways used to build and shape excretory tubes appear similar to those used in both unicellular and multicellular tubes in more complex organs, such as the vertebrate vascular system and kidney, making this simple organ system a useful model for understanding disease processes. [ABSTRACT FROM AUTHOR]

Juvenile and adult Cossura pygodactylata Jones 1956 from the White Sea were studied using confocal laser scanning microscopy, light microscopy, scanning and transmission electron microscopy. Transformations of the anterior musculature and digestive tract during ontogenesis were investigated. The early juveniles were shown to be lecithotrophic; their pharyngeal cavities were not connected to the intestines, which contained yolk granules. The juveniles bore prototrochs, which are used for movement, although juveniles had parapodial musculature similar to that of the adults. The juveniles presumably inhabit the upper semi-liquid layer of the silt. The muscles of the prostomium and circumbuccal complex change dramatically during ontogenesis. The ultrastructure of the buccal tentacles is redescribed. The tentacles consist of outer ciliated epithelial cells and an inner cylinder formed by epithelio-muscle cells. The blood sinus is situated between the central cylinder and the epithelium. Both juveniles and adults have developed circulatory systems. The whole dorsal vessel forms the heart with walls that consist of cells with circular cross-striated muscular fibres. The inner lumen is occluded by the heart body which is formed by a single row of cells that are tightly pressed together and connected by adherens junctions along their anterior and posterior surfaces. They contain granules and vesicles and bear numerous processes on the outer surface. The heart body most likely has a secretory haemopoetic function. A hypothetical mechanism of protraction and retraction of the buccal tentacles is suggested, and the participation of muscle contraction and relaxation in these movements is described. It is proposed that the protraction of the tentacles is provided by cell rigidity and increases in the blood volume in the tentacles blood sinuses. The development of the circulatory system is likely related to the need to keep the tentacles exposed during feeding while the anterior part of the body cavity is filled with muscle cell processes and there is no coelomic liquid flow. The proposed mechanism of feeding inside the sediment contrasts with that of surface feeding suggested by Tzetlin (Mém Mus Natl Hist Nat 162:137-143, ). [ABSTRACT FROM AUTHOR]

Many soft-bodied invertebrates use a flexible, fluid-filled hydrostatic skeleton for burrowing. The aim of our study was to compare the scaling and morphology between surface-dwelling and burrowing earthworm ecotypes to explore the specializations of non-rigid musculoskeletal systems for burrowing locomotion. We compared the scaling of adult lumbricid earthworms across species and ecotypes to determine whether linear dimensions were significantly associated with ecotype. We also compared the ontogenetic scaling of a burrowing species, Lumbricus terrestris, and a surface-dwelling species, Eisenia fetida, using glycol methacrylate histology.We show that burrowing species are longer, thinner and have higher length-to-diameter ratios than non-burrowers, and that L. terrestris is thinner for any given body mass compared with E. fetida. We also found differences in the size of the musculature between the two species that may correlate with surface crawling or burrowing. Our results suggest that adaptations to burrowing for soft-bodied animals include a disproportionately thin body and strong longitudinal muscles. [ABSTRACT FROM AUTHOR]

Epigeic earthworms can significantly hasten the decomposition of organic matter, which is known to be mediated by gut associated microflora. However, there is scanty information on the abundance and diversity of the gut bacterial flora in different earthworm genera fed with a similar diet, particularly Eisenia foetida and Perionyx excavatus . In this context, 16S rDNA based clonal survey of gut metagenomic DNA was assessed after growth of these two earthworms on lignocellulosic biomass. A set of 67 clonal sequences belonging to E. foetida and 75 to P. excavatus were taxonomically annotated using MG-RAST and RDP pipeline servers. Highest number of sequences were annotated to Proteobacteria (38–44%), followed by unclassified bacteria (14–18%) and Firmicutes (9.3–11%). Comparative analyses revealed significantly higher abundance of Actinobacteria and Firmicutes in the gut of P. excavatus. The functional annotation for the 16S rDNA clonal libraries of both the metagenomes revealed a high abundance of xylan degraders (12.1–24.1%). However, chitin degraders (16.7%), ammonia oxidizers (24.1%) and nitrogen fixers (7.4%) were relatively higher in E. foetida , while in P. excavatus ; sulphate reducers and sulphate oxidizers (12.1–29.6%) were more abundant. Lignin degradation was detected in 3.7% clones of E. foetida , while cellulose degraders represented 1.7%. The gut microbiomes showed relative abundance of dehalogenators (17.2–22.2%) and aromatic hydrocarbon degraders (1.7–5.6%), illustrating their role in bioremediation. This study highlights the significance of differences in the inherent microbiome of these two earthworms in shaping the metagenome for effective degradation of different types of biomass under tropical conditions. [ABSTRACT FROM AUTHOR]

The article 'Structure of the nervous system of the nematode Caenorhabditis elegans' (aka 'The mind of a worm') by White et al., published for the first time the complete set of synaptic connections in the nervous system of an animal. The work was carried out as part of a programme to begin to understand how genes determine the structure of a nervous system and how a nervous system creates behaviour. It became a major stimulus to the field of C. elegans research, which has since contributed insights into all areas of biology. Twenty-six years elapsed before developments, notably more powerful computers, made new studies of this kind possible. It is hoped that one day knowledge of synaptic structure, the connectome, together with results of many other investigations, will lead to an understanding of the human brain. This commentary was written to celebrate the 350th anniversary of the journal Philosophical Transactions of the Royal Society. [ABSTRACT FROM AUTHOR]

This study describes a new and sensitive method for measuring the in vivo and in vitro cytotoxicity of 2 earthworm species, Eisenia andrei and Perionyx excavatus , exposed to copper. Specifically, we measured the number of coelomocyte cells that were affected by copper following in viv o and in vitro exposure by flow cytometry, after calcein acetoxymethyl ester (calcein-AM) staining. We found that the coelomocyte viability of both earthworm species was noticeably reduced in the in vivo cytotoxicity test at concentrations of 100 mg/kg copper in dry soil. However, pathological symptoms, such as mucous secretion and bleeding, swelling, thinning, and fragmentation, and burrowing symptoms were not evident following exposure to copper levels of <400 mg/kg dry soil. In conclusion, the present study demonstrates that calcein-AM is a more sensitive test of earthworm coelomocyte cytotoxicity compared to the traditional individual level toxicity test. Therefore, this test could be used to detect low levels of metal contamination in soils. [ABSTRACT FROM AUTHOR]

Eupanthalis rudipalpa Amaral & Nonato, 1984 was described based on three incomplete, colorless specimens and has not been reported since its original description; the epithet rudipalpa means "hirsute palps", a characteristic that separates it from other congeneric species. Eupanthalis Mcintosh, 1876 and Euarche Ehlers, 1887, and their respective type species, E. kinbergi Mcintosh, 1876 and E. tubifex Ehlers, 1887, were considered synonyms (E. rudipalpa as a junior synonym of E. tubifex, a cosmopolitan species) by some authors, because both have sessile eyes and two or three antennae. Nonetheless, these two genera are, in fact, distinct. Their type species can clearly be separated using some prostomial features. We provide an emended diagnosis of Euarche, and re-instate E. rudipalpa, redescribing it based on a Brazilian specimen (original type specimens lost). Illustrations showing body pigmentation pattern and a key to all species of Eupanthalis are also provided. [ABSTRACT FROM AUTHOR]

Abstract: With seven described species Tubiluchus is the most species-rich genus among priapulids. We here describe a new species, Tubiluchus lemburgi sp. nov., from the island of Tenerife (Canary Islands). All Tubiluchus species are very similar morphologically, but show distinct differences in the genital region of males. The new species differs from any other described Tubiluchus in the presence of a clearly demarcated genital region bordered by a cuticular ridge, the shape of the genital openings and the distribution of cuticular structures. [Copyright &y& Elsevier]

Polyclad flatworms are an early branching clade within the rhabditophoran Platyhelminthes. They provide an interesting system with which to explore the evolution of development within Platyhelminthes and amongst Spiralia (Lophotrochozoa). Unlike most other flatworms, polyclads undergo spiral cleavage (similar to that seen in some other spiralian taxa), they are the only free-living flatworms where development via a larval stage occurs, and they are the only flatworms in which embryos can be reared outside of their protective egg case, enabling embryonic manipulations. Past work has focused on comparing early cleavage patterns and larval anatomy between polyclads and other spiralians. We have selected Maritigrella crozieri, the tiger flatworm, as a suitable polyclad species for developmental studies, because it is abundant and large in size compared to other species. These characteristics have facilitated the generation of a transcriptome from embryonic and larval material and are enabling us to develop methods for gene expression analysis and immunofluorescence techniques. Here we give an overview of M. crozieri and its development, we highlight the advantages and current limitations of this animal as a potential evo-devo model and discuss current lines of research. [ABSTRACT FROM AUTHOR]