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The article discusses the phrase "diet of worms" and its various interpretations. Historians associate it with a political convocation in Worms, Germany in 1521, while nutritionists consider whether humans could survive on a diet of earthworms. A recent study analyzed different techniques for gathering earthworms and concluded that such a diet would not be feasible or recommended unless faced with starvation. The article also mentions other scientific studies on the diets of worms themselves and the potential health impacts of consuming them. Additionally, it briefly mentions a news report about height requirements for admission to a university in Vietnam and requests examples of strict height prohibitions in science, medical, or tech institutions. Finally, it includes a humorous anecdote about a septic tank slogan. [Extracted from the article]

A recent study conducted by the Russian Academy of Sciences has discovered a novel antimicrobial peptide called AmBRI-44a in the marine polychaete Arenicola marina. This peptide has shown potential as an antibiotic agent against multidrug-resistant Gram-positive bacteria. The study investigated the structure, activity, and mechanism of action of AmBRI-44a, and found that it has a specific activity against a narrow spectrum of bacteria and cytotoxic effects on eukaryotic cells. The research suggests that AmBRI-44a could be a candidate compound for the development of new antibiotics to treat infectious diseases. [Extracted from the article]

Metchnikovellids are a deep-branching group of microsporidia, parasites of gregarines inhabiting the alimentary tract of polychaetes and some other invertebrates. The diversity and phylogeny of these hyperparasites remain poorly studied. Modern descriptions and molecular data are still lacking for many species. The results of a light microscopy study and molecular data for Metchnikovella spiralis Sokolova et al., 2014, a hyperparasite of the eugregarine Polyrhabdina sp., isolated from the polychaete Pygospio elegans, were obtained. The original description of M. spiralis was based primarily on the analysis of stained preparations and transmission electron microscopy images. Here, the species description was complemented with the results of in vivo observations and phylogenetic analysis based on the SSU rRNA gene. It was shown that in this species, free sporogony precedes sac-bound sporogony, as it occurs in the life cycle of most other metchnikovellids. Spore sacs are entwined with spirally wound cords, and possess only one polar plug. Phylogenetic analyses did not group M. spiralis with M. incurvata, another metchnikovellid from the same gregarine species, but placed it as a sister branch to Amphiacantha. The paraphyletic nature of the genus Metchnikovella was discussed. The taxonomic summary for M. spiralis was emended. [ABSTRACT FROM AUTHOR]

A recent study conducted by the Russian Academy of Sciences has provided new insights into the structure and mechanism of action of the antimicrobial peptide capitellacin. Capitellacin, derived from the marine polychaeta Capitella teleta, has shown antibacterial activity against drug-resistant strains. The study used high-resolution NMR spectroscopy to analyze the structure of capitellacin in a membrane-mimicking environment. The researchers observed that capitellacin exists in two structural forms, a monomeric b-hairpin and a dimer stabilized by intermonomer hydrogen bonds and Van der Waals interactions. The study also found that the stability and hemolytic activity of b-hairpin antimicrobial peptides are positively correlated with surface hydrophobicity. This research provides a more accurate understanding of the oligomerization mechanism of b-structural peptides in biological membranes. [Extracted from the article]

The duognathous haemadipsid leeches of the genus Chtonobdella show a trans-oceanic distribution throughout the Indo-Pacific region. Although passive long-distance dispersal (LDD) of Chtonobdella leeches by birds has been suggested, little is known about the host–parasite relationships between avian hosts and Chtonobdella leeches. In the current study, we investigated Chtonobdella leech infestations of the eyes and other mucus membranes of migratory procellariiform seabirds, Pterodroma hypoleuca and Oceanodroma tristrami, captured at six locations in the Bonin Islands, Honshu and Okinawa Island, Japan. Analyses of the partial sequences of 18S rRNA, 28S rRNA, and mitochondrial cytochrome c oxidase subunit I (COI) and morphological examination of the specimens demonstrated that the Chtonobdella leeches belonged to Chtonobdella palmyrae, which is indigenous to Palmyra Atoll in the Northern Line Islands. A dominant COI sequence type was observed in samples from all six sites; therefore, C. palmyrae almost surely dispersed approximately 1000 km by infesting the eyes and mucus membranes of procellariiform seabirds. The host–parasite relationships between procellariiform seabirds and C. palmyrae provide explicit evidence of the LDD of duognathous haemadipsid leeches. The taxonomic status of Haemadipsa zeylanica ivosimae from the Volcano Islands is also briefly discussed. [ABSTRACT FROM AUTHOR]

Known life cycles of myxosporean parasites have two hosts, but very few life cycles have been disclosed, especially in the marine environment. Sphaerospora dicentrarchi Sitjà-Bobadilla and Álvarez-Pellitero, 1992 is a systemic parasite from the European seabass, Dicentrarchus labrax (Linnaeus, 1758), a highly valuable commercial fish. It affects its health, leading to aquaculture production losses. During 2013 and 2014, an actinospore survey was conducted in a total of 5942 annelids collected from a fish farm in Algarve and from the Aveiro Estuary, in Portugal. A new tetractinomyxon actinospore was found in a capitellid polychaete, belonging to the genera Capitella collected at the fish farm. The tetractinomyxons were pyriform measuring 11·1 ± 0·7 µm in length and 7·2 ± 0·4 µm in width, and presented three rounded polar capsules measuring 2·4 ± 0·3 µm in diameter. The molecular analysis of the 18S rRNA gene sequences from the tetractinomyxons revealed a similarity of 100% with the DNA sequences deposited in the GenBank from S. dicentrarchi myxospores collected from the European seabass and the spotted seabass in the same fish farm and 99·9% similarity with the DNA sequence obtained from the myxospores found infecting the European seabass in the Aveiro Estuary. Therefore, the new tetractinomyxons are inferred to represent the actinospore phase of the S. dicentrarchi life cycle. [ABSTRACT FROM AUTHOR]

Marine infaunas influence sediment chemistry, nutrient cycling, and microbial communities as they burrow, feed, defecate, and irrigate their tubes and burrows. Nonlethal tissue loss to predators or other disturbances is frequently observed in macrofaunal communities, and previous research has reported significant effects of onetime injury on animal activity. In this study, we examined the effects of injury and nutrient enrichment on sediment reworking rates of a common deposit-feeding polychaete, Clymenella torquata. Individualworms in cores were monitored in a recirculating seawater system, and their defecation and sediment mixing monitored under several experimental conditions. Worms held in control (unenriched) sediment or in homogeneously diatom-enriched sediment were injured on days 0 and 7 in a 21 d experiment. Worms held in control sediment or sediment with high surface diatom enrichment were observed in a 7 d experiment following repeated injury. Posterior segments were ablated for the injury treatments, and injury and nutrient supply treatments were crossed in all experiments. Repeated injury significantly decreased surface activities and defecation, and injured worms transported significantly less surface sediment to depth than intact worms. Microalgal enrichment at the sediment surface correlated with an increase in bioturbation; intactworms in surfaceenriched sediments were more active and more likely to hoe surface sediments to depth as evidenced by vertical profiles. These findings help explain how infaunal activities are modified by injury and food availability and can be used to improve models of bioturbation to further elucidate complex benthic community dynamics. [ABSTRACT FROM AUTHOR]

The present paper reports results of a transmission electron microscopy study of a new metchikovellid microsporidium. It was isolated from gregarines Polyrhabdina sp. inhabiting guts of polychaetes Pygospio elegans sampled at the White Sea silt littoral zone. Free sporogony (FS) occurred in the life cycle of the microsporidium alongside sac-bound sporogony (BS). Free spores resided in a parasitophorous vacuole and were of typical metchnikovellidean structure, uninucleate and oblong. They measured on sections 2·0–3·2×1·3–1·9 μm. The life cycle included pre-sporogonial stages represented by dikaryotic cells and 4-nucleate cells with coupled nuclei. A multinucleate sporogonial plasmodium of FS split in numerous (>10) sporoblasts. In BS segregation of sporoblasts occurred within thick-walled cysts by internal budding. Spore sacs of this microsporidium, measuring on average 11·6×4·7 μm, were limited by a thick electron-dense wall, externally ornamented with spirally wound cords of dense material. These oval spore sacs contained eight barrel-shaped spores, comparable in size and ultrastructure to FS spores. Ultrastructure of both types of spores and intracellular development of the new microsporidium and Metchnikovella spp. were similar, suggesting they belong to the same genus. In this paper we describe a new species Metchnikovella spiralis and discuss morphology of metchnikovellids in the context of putative evolutionary history of Microsporidia. [ABSTRACT FROM PUBLISHER]

Class Rudimicrosporea Sprague 1977, with its single family Metchnikovellidae, comprises hyperparasites of gregarines from the guts of marine invertebrates. Metchnikovellids remain poorly studied in spite of their significance to the evolutionary history of microsporidia; their ultrastructure and life cycles require further investigation. Here we present results of the light- and electron-microscopy study of Metchnikovella incurvata Caulleri and Mesnil 1914, isolated from lecudinid gregarines, parasitizing polychaetes Pygospio elegans in the White Sea littoral zone, and yet described only on the light-microscopic level. The life cycle of this microsporidium includes 2 sporogonies: free (FS) and sac-bound (SBS). In FS, sporonts develop into multinuclear cells (sporogonial plasmodia), which generate sporoblasts and free spores residing in direct contact with the host cytoplasm. Electron microscopy revealed their metchnikovellidean structure: a horseshoe-shaped nucleus, short manubrium perpendicular to the long axis of the spore, and a polar cap in a separate membrane container. Merogony was not observed. The earliest stages of SBS were chains of binucleate cells. They underwent a series of nuclear and cell divisions, produced extracellular envelopes, and split into boomerang-shaped spore sacs, containing up to 16 spores each. Ultrastructure and sizes of sac-bounded spores were similar to those of free-living ones. An amended diagnosis of M. incurvata is provided. [ABSTRACT FROM AUTHOR]

Recent advances in understanding of sediment material properties and of burrowing mechanics suggest likely differences in the behavior of organisms burrowing in mud and sand. The path of least resistance in the mud may lead an infaunal organism to burrow along a rigid wall. By contrast, in sand, force chains may prevent a burrowing organism from reaching a rigid wall. Burrowing in mud occurs primarily by the propagation of cracks. Cracks, and hence burrows, tend to propagate along rigid walls. In sand, force chains comprise collections of particles that experience much more stress than their neighbors. Stress chains tend to terminate at walls where their high density may inhibit burrowing. To test for differing effects of mud and sand on the spatial distribution of infauna, proximity to a rigid wall of two polychaetes, Alitta virens and Clymenella torquata, was measured in sand and mud. For both species the cumulative density distribution of burrow distances from the wall showed significantly more burrows near the wall than expected in both mud and sand. However, in direct sampling experiments, the more mobile A. virens showed a greater tendency to burrow at the wall in mud than in sand and strong exclusion from the immediate vicinity of the wall in sand, whereas C. torquata did not show a significant difference in distance from the wall in sand versus mud. The wall effect may be weaker for C. torquata because its limited mobility makes it less likely to encounter a wall over the course of an experiment. Our results point to the need for quantitative assessment of biases of analytical devices that rely on rigid walls, such as optodes and sediment profile imaging cameras, and suggest a possible similar bias in animal distributions around natural analogs such as rock-sediment boundaries. [ABSTRACT FROM AUTHOR]

In Mar Chiquita coastal lagoon (Argentina), the reefs of the invasive polychaete Ficopomatus enigmaticus (Serpulidae) serve as concentration areas for invertebrates and vertebrates and as potential foci of parasite transmission (mainly digeneans). To analyse the role of F. enigmaticus as facilitator of parasite transmission, and to evaluate the influence of the habitats selected by 2 species of cochliopid snails (Heleobia conexa and Heleobia australis), on the richness and on the prevalence of the digenean assemblages that parasitize them, 1945 snails were collected from 2 sampling sites. The comparisons between larval digenean communities parasitizing both snail hosts revealed significant differences related to the overall prevalence and the prevalence contributed by birds in the snails collected from reefs. These results support the idea that the reefs may increase the number of links between intermediate and definitive hosts of digeneans, facilitating parasite transmission only when the aggregates of F. enigmaticus become the unique habitat of the snail host. This first report of an exotic species acting as facilitator of parasite transmission in an estuarine area highlights the importance of analysing the effects of the assimilation process of exotic species by recently colonized environments (including the possible effects on parasite transmission). [ABSTRACT FROM PUBLISHER]

When the LEO-IS (Long-term Ecosystem Observatory at 15-rn depth) research area was designated around Beach Haven Ridge (39°27.69' N, 74°15.81' W) in the early 1990's several stations were selected to reflect the different physical regimes and habitats present in a highly dynamic shelf environment. This study determined the composition, diversity, and abundance of infaunal communities at three contrasting stations on five dates in 1994-1995. A unique sampling scheme was used where a nested design was combined with targeted sampling by divers of benthic topographic habitat features, namely crests and troughs of sand ripples. The total number of taxa collected was 148. The majority of taxa (80%) were either ubiquitous (67 taxa, 45%) or had an apparent affinity for a single station (52 taxa, 35%). The polychaete Polygordius jouinae was numerically dominant. The three distinctive stations 2-4 km apart, the date of sampling and, somewhat surprisingly, whether or not samples were taken in adjacent crests or troughs, all contributed to the structure of LEO-is infaunal communities. Together these three stations character- ize the sediments and fauna in the LEO-IS research area and form the basis for future studies of short and longer-term changes, and of the processes and mechanisms responsible for the patterns observed. [ABSTRACT FROM AUTHOR]

We recorded the nereidid polychaete Leonnates persicus Wesenberg-Lund, 1949, previously known from coasts of Indian Ocean and western Pacific Ocean, from the coasts of Japan, Korea, and Thailand, based on examination of 27 specimens collected from shallow subtidal or intertidal muddy flats at 16 localities. The morphological characteristics of this material agreed well with those of the holotype from the Persian Gulf. We describe some important new characteristics of the holotype, which had not been appropriately described in previous literature. [ABSTRACT FROM AUTHOR]

The genus Haplosyllides was considered as monotypic, with H. floridana as the only valid species. The present revision includes two more species in this genus: H. aberrans comb. nov. and H. ophiocomae sp. nov. SyIIis (Haplosyllis) aberrans (from Vietnam) was considered a junior synonym of H. floridana (from the Caribbean). The finding of additional specimens from Vietnam and Indonesia, and the study of the type series, allowed us to redescribe H. aberrans comb. nov. on the basis of morphological, ecological and biogeographical characteristics; Haplosyllides aberrans comb. nov. differs from H. floridana in having posterior simple chaetae with tips twice as long, a pharyngeal tooth in all non-reproductive individuals, and the granules inside the dorsal cirri oval, elongated, and roughly distributed in longitudinal parallel rows. Haplosyllides ophiocomae sp. nov. was previously reported (as H. aberrans) from Puerto Rico. Although geographically close, it differs from H. floridana in having serration on the upper edge of the major teeth of simple chaetae, relatively shorter dorsal cirri, and a distinct mode of life. Haplosyllides floridana lives as an endosimbiont of Xetospongia muta, H. aberrans comb. nov. as a facultative parasite of Platycaris latirostris, and H. ophiocomae sp. nov. as a commensal of Ophiocoma pumila and other brittle stars. The meaning of these associations is discussed in light of the available information. The remaining records of "Haplosyllides aberrans" from the Marshall Islands (associated with corals of the genus Heliopora) and from Brazil (among corals and calcareous algae) are considered as doubtful. [ABSTRACT FROM AUTHOR]

A total of 11 specimens of a nereidid polychaete, which had been collected from the inner part ("Bay of Miya" is the old place name) of Ise Bay in central Japan and preserved in the Natural History Museum Vienna, were taxonomically examined. They were all identified as the brackish-water nereidid, Hediste japonica (Izuka, 1908), which was previously known only from the Ariake Sea and Seto Inland Sea in western Japan and the western coast of Korea. The new information indicates that this species formerly had a wider distribution extending to at least Ise Bay in central Japan, though all Japanese populations of this species seem to have been extirpated except for a population remaining in the Ariake Sea. [ABSTRACT FROM AUTHOR]

Most spionid polychaetes switch from surface deposit feeding to suspension feeding as current speed and the flux of suspended food increase. Previous experiments testing the effects of flow on the growth of facultative, interface feeders have been limited to very simplified flow regimes such as constant, unidirectional currents. To measure the growth of interface-feeding spionids in more realistic currents, we programmed two identical counter-rotating annular flumes to simulate two different semidiurnal tidal currents. Each regime included four speeds that varied in hourly steps. At 5 mm above bottom, speeds in the slower flow regime were 0, 2.5, 5, and 7.5 cm s-1. Speeds in the faster regime were 0, 4, 8, and 12 cm s-1. Every 6 h, after each hour at 0 cm s-1, the flume rotation was reversed to simulate the directional shift between ebb and flood currents. The 12-h periods were repeated over 96 h. The experiment included eight 4-d runs of paired slow- and fast-flow flumes. Field-collected sediment and a nonliving algal slurry were added to control deposited and suspended food. Individuals of four species were measured for body volumes before and after each 4-d run: Polydora cornuta, Streblospio benedicti, Pygospio elegans, and Spio setosa. Each species except S. setosa was divided a priori into two size classes. Both small and large P. cornuta grew significantly faster in the fast-flow regime. Large P. elegans grew significantly faster in the fast-flow regime, but the growth rates of small P. elegans did not differ between regimes. Neither size class of S. benedicti grew at significantly different rates between flow regimes, and the broad size class of S. setosa did not show significant flow-dependent growth. The significant growth responses of two of the four species to moderate differences in tidal flow over a short time period underscore the impact flow can have on the population dynamics of some interface-feeding spionids. The differences among species suggest that variability in tidal currents can influence the structure and dynamics of communities in which spionids are often important and abundant. [ABSTRACT FROM AUTHOR]

Two new species of Spiochaetopterus (Chaetopteridae: Polychaeta), S. sanbanzensis, from Sanbanze, off Ichikawa and Funabashi Cities, Tokyo Bay, and S. izuensis from the shallow waters of Sagami Bay, were described. The most obvious difference is the number of segments in region A: 9 in S. sanbanzensis and 10 in S. izuensis. In addition, Spiochaetopterus sanbanzensis has elliptical light brown or blackish eye-spots, asymmetrical cordate specialized A4 chaetæ, and a color pattern consisting of many dispersed brown spots on both ventral and dorsal faces of region A. In Spiochaetopterus izuensis, a brown band extends from each eye-spot to the level of the A1 chaetae; the convex ventral edge of the head of the specialized A4 chaeta has an oblique section and the color pattern of the body is absent. A comparison is established between these two new species and other known species from Indo-Pacific Ocean [ABSTRACT FROM AUTHOR]

Presents the winning essay in the Wellcome Trust/'New Scientist' 2000 Millennial Essay Competition for postgraduate students. What author Adrian Glover said on the topic of polychaetes, or marine worms, and the zoological impact on the ocean; Biographical information.

Examines the relative importance of four colonization mechanisms for seven numerically dominant polychaete species in an intertidal estuarine sandflat in Connecticut. Definition of colonization mechanism; Species with nonplanktonic development.

Examines the effects of fluid flow, bed characteristics and suspended load on the feeding behavior of four species of marine polychaetes. Exposure of polychaete species to a series of bed and flow treatments in the laboratory; Relation of time-spent suspension feeding to the flux of suspended high organic matter; Correlates of suspension feeding behavior.

Studies individual physiological responses of the polychaete Capitella species to hypoxia and organic enrichment in coastal marine environments. Parallelism between faunal and geochemical changes; Dominance of the specie in the initial changes of succession; Temporal stability of the specie populations within highly enriched sediments.

Examines the effects of porewater hydrogen sulfide concentrations on the feeding and tube-building activity of the subsurface, deposit-feeding polychaete, Clymenella torquata, in the laboratory. Injection of buffered isotonic sodium sulfide solution; Fecal production; Tube-building frequencies.

Investigates potential carbon sources for the capitellid polychaete Heteromastus filiformis. Ingestion of sediment by the head-down deposit feeder; Worm's ability to acquire food and oxygen; Examination of food sources.

Provides information on polychaete, a marine worm that is shaped like a heart, which was photographed by Chris Newbert in the Solomon Islands of the South Pacific. Description of the worm in the photograph; Characteristics of worms of the order Sabellida; Purposes of the long appendages on the head of such worms.

Reports on marine biologist James Hunt's discovery of marine worms called polychaetes while exploring the Japan Trench 21,000 feet deep aboard the Shinkai 6500, the world's deepest-diving manned submersible. Transparency of the worm's organs; Locomotion; Possibility of finding more life at these depths.

A microsocopic of the polychaete worm of the Terebellidae family is presented.

The article offers information on the study conducted by E. Ricevuto, S. Vizzini, and M. C. Gambi concerning the effects of ocean acidification on tropic interactions of polychaete species and organic matter sources in a natural potential of hydrogen (pH) gradient.

The article discusses research on the response of polychaetes to ocean acidification. It references a study by P. Calosi and colleagues published in the 2014 issue of "Philosophical Transactions of the Royal Society B." Topics covered include the sensitivity of polychaetes to environmental perturbation, ability of the organ to function in a changing area and potential of the organism for metabolic adaptation. Also mentioned is the impact of ocean acidification on marine ectotherms.

The article discusses a report in the July 29, 2013 "Proceedings of the National Academy of Sciences," by earth scientist Erik Sperling and team on the role of increasing atmospheric oxygen on the evolution of carnivore predator species which led to the Cambrian explosion of animal diversity. The researchers looked at sea floor polychaetes around the world, finding that the number of carnivorous species correlated strongly with local oxygen levels.

Se presenta una noticia breve sobre el descubrimiento de tres tipos de anélidos poliquetos (gusanos marinos) y oxiuros (estrellas serpientes) en el mar entre Loreto y la Paz, Baja California Sur en México por científicos del Instituto de Ciencias del Mar y Limnología de la Universidad Nacional Autónoma de México (UNAM). Se nota que la zona del descubrimiento se caracteriza por un terreno submarino rocoso y profundidades de hasta 300 metros.

A new whale-bone-eating polychaete species of the genus Osedax was found on sperm whale carcasses submerged off Cape Nomamisaki, Kyushu, Japan, at a depth of approximately 200 m. The new species, Osedax japonicus, is the fourth known species of the genus Osedax and the first species from the western Pacific. Female O. japonicus specimens (1) form dense clusters on whale carcasses; (2) have a body composed of crown, trunk, and root structure; (3) lack a digestive tract; and (4) have bacterium-like particles in the tissue of the root structure. Osedax japonicus shares all these characteristics with O. rubiplumus and O. frankpressi, and items (1) to (3) with O. mucofloris. Osedax japonicus is easily distinguished from the other three known species by oviduct morphology, body length, and palp coloration in females. No males of O. japonicus have yet been found. [ABSTRACT FROM AUTHOR]

Details the need of identifying and studying polychaetes. Role in climate control; Concern over the extinction of the species; Efforts of Kristian Fauchald, a museum curator at the Smithsonian Institute.

Presents information on tube worms.

Focuses on the significance of life cycles on the population dynamics of polychaetes Streblospio benedicti and Capitella sp. 1. Effects of various pollutants on life cycles; Effects of nutrients and light.