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The endangered continental Black-tailed Godwit ( Limosa limosa limosa) is a migratory ground-nesting wader breeding in a wide variety of open, wet habitats across Europe. Conservation research has concentrated on the causes of population decline, but we know surprisingly little about whether any resources limit local breeding populations and if so, whether these are resources for the adults or the chicks. We collected data from 63 key breeding sites in five countries across Europe to test whether, after correcting for differences in surveyed areas, the size of Godwit breeding populations was related to environmental variables (vegetation biomass, soil moisture) or food resources for adult birds (soil invertebrates) or chicks (vegetation dwelling arthropods) measured during different times of the reproductive cycle. We found the number of Godwit territories to be positively related to arthropod abundance during the chick-hatching period. We found additional, weaker support for a positive relation between Godwit territory numbers and the abundance of soil-dwelling invertebrates (mostly earthworms) at clutch laying, but not at chick-hatching. These relationships were observed across countries, while we found little support for relationships within countries, possibly due to the smaller range in conditions that exist within countries. Both vegetation growth and soil moisture weren’t related to Godwit territory numbers. Our results suggest that food abundance for chicks, and to a lesser extent adult birds, are key factors determining the size of local Godwit breeding populations. Conservation management aiming to enhance local Godwit populations should therefore consider the impacts of management strategies on the arthropod prey of chicks.

In seasonal environments subject to climate change, organisms typically show phenological changes. As these changes are usually stronger in organisms at lower trophic levels than those at higher trophic levels, mismatches between consumers and their prey may occur during the consumers’ reproduction period. While in some species a trophic mismatch induces reductions in offspring growth, this is not always the case. This variation may be caused by the relative strength of the mismatch, or by mitigating factors like increased temperature-reducing energetic costs. We investigated the response of chick growth rate to arthropod abundance and temperature for six populations of ecologically similar shorebirds breedingin the Arctic and sub-Arctic (four subspecies of Red Knot Calidris canutus, Great Knot C. tenuirostris and Surfbird C. virgata). In general, chicks experienced growth benefits (measured as a condition index) when hatching before the seasonal peak in arthropod abundance, and growth reductions when hatching after the peak. The moment in the season at which growth reductions occurred varied between populations, likely depending on whether food was limiting growth before or after the peak. Higher temperatures led to faster growth on average, but could only compensate for increasing trophic mismatch for the population experiencing the coldest conditions. We did not find changes in the timing of peaks in arthropod availability across the study years, possibly because our series of observations was relatively short; timing of hatching displayed no change over the years either. Our results suggest that a trend in trophic mismatches may not yet be evident; however, we show Arctic-breeding shorebirds to be vulnerable to this phenomenon and vulnerability to depend on seasonal prey dynamics.

Leizhou Bay in Guangdong Province is the most important wintering site inChina for the critically endangered Spoon-billed Sandpipers ( Calidris pygmaea). As food is usually a strong predictor of presence, in the winters of 2019-2022 we studied arthropod food resources and diet on the intertidal mudflats at the Tujiao and Hebei mudflats in Leizhou Bay. In December 2020, using a sampling device that encloses mobile epibenthic prey before the human sampler would disturb them in shallow pools, we visited 34 stations in their core foraging area at Tujiao. A total of 15 mobile benthic species were identified, including 13 arthropod and 2 fish species, with a total density of 106 animals/m2 (range= 0.2-48 animals/m2), with the lengths of the animals ranging from 1-19 mm. Two amphipod and one cumacean species contributed 85%. On the basis of photographs of foraging during low tide in 2019-2022, the visibly ingested prey items appeared to mainly consist of small shrimp, but also included crabs and fish. At 27 mm (compared with the 22 mm long bill of Spoon-billed Sandpipers) the average visibly ingested prey showed a strong size bias. Among the measured environmental covarying factors (sediment pH, salinity, TOC content, median particle size and distance from the seawall etc.) potentiually affecting the mobile epibenthic prey in shallow pools, only distance from the seawall was significantly and negatively correlated. Densities were higher within 1 km of the seawall (126 animals/m2) than further offshore (69 animals/m2 ). This may relate to the mangrove forests growing in abundance near the seawall providing released minerals, nutrients, bacterial production and diatoms for the benthic community in the adjacent mudflats. However, the potential negative impact of artificial mangrove expansion in Leizhou mudflats need to be carefully monitored and assessed to balance both mangrove and Spoon-billed Sandpipers conservation.

Exon Primed Intron Crossing (EPIC) markers provide molecular tools that are susceptible to be variable within species while remaining amplifiable by PCR using potentially universal primers. In this study we tested the possibility of obtaining PCR products from 50 EPIC markers on 23 species belonging to seven different phyla (Porifera, Cnidaria, Arthropoda, Nematoda, Mollusca, Annelida, Echinodermata) using 70 new primer pairs. A previous study had identified and tested those loci in a dozen species, including another phylum, Urochordata (Chenuil et al., 2010). Results were contrasted among species. The best results were achieved with the oyster (Mollusca) where 28 loci provided amplicons susceptible to contain an intron according to their size. This was however not the case with the other mollusk Crepidula fornicata, which seems to have undergone a reduction in intron number or intron size. In the Porifera, 13 loci appeared susceptible to contain an intron, a surprisingly high number for this phylum considering its phylogenetic distance with genomic data used to design the primers. For two cnidarian species, numerous loci (24) were obtained. Ecdysozoan phyla (arthropods and nematodes) proved less successful than others as expected considering reports of their rapid rate of genome evolution and the worst results were obtained for several arthropods. Some general patterns among phyla arose, and we discuss how the results of this EPIC survey may give new insights into genome evolution of the study species. This work confirms that this set of EPIC loci provides an easy-to-use toolbox to identify genetic markers potentially useful for population genetics, phylogeography or phylogenetic studies for a large panel of metazoan species. We then argue that obtaining diploid sequence genotypes for these loci became simple and affordable owing to Next-Generation Sequencing development. Species surveyed in this study belong to several genera ( Acanthaster, Alvinocaris, Aplysina, Aurelia, Crepidula, Eunicella, Hediste, Hemimysis, Litoditis, Lophelia, Mesopodopsis, Mya, Ophiocten, Ophioderma, Ostrea, Pelagia, Platynereis, Rhizostoma, Rimicaris), two of them, belonging to the family Vesicomydae and Eunicidae, could not be determined at the genus level. © 2013 Elsevier B.V.

The taxon Arthropoda has been repeatedly cited with various incorrect authorship data. Here, we review the primary literature and show the correct citation to be 'Arthropoda Von Siebold, 1848'.

Extreme weather events can have negative impacts on species survival and community structure when surpassing lethal thresholds. Extreme winter warming events in the Arctic rapidly melt snow and expose ecosystems to unseasonably warm air (2-10 °C for 2-14 days), but returning to cold winter climate exposes the ecosystem to lower temperatures by the loss of insulating snow. Soil animals, which play an integral part in soil processes, may be very susceptible to such events depending on the intensity of soil warming and low temperatures following these events. We simulated week-long extreme winter warming events - using infrared heating lamps, alone or with soil warming cables - for two consecutive years in a sub-Arctic dwarf shrub heathland. Minimum temperatures were lower and freeze-thaw cycles were 2-11 times more frequent in treatment plots compared with control plots. Following the second event, Acari populations decreased by 39%; primarily driven by declines of Prostigmata (69%) and the Mesostigmatic nymphs (74%). A community-weighted vertical stratification shift occurred from smaller soil dwelling (eu-edaphic) Collembola species dominance to larger litter dwelling (hemi-edaphic) species dominance in the canopy-with-soil warming plots compared with controls. The most susceptible groups to these winter warming events were the smallest individuals (Prostigmata and eu-edaphic Collembola). This was not apparent from abundance data at the Collembola taxon level, indicating that life forms and species traits play a major role in community assembly following extreme events. The observed shift in soil community can cascade down to the micro-flora affecting plant productivity and mineralization rates. Short-term extreme weather events have the potential to shift community composition through trait composition with potentially large consequences for ecosystem development. © 2011 Blackwell Publishing Ltd.

Extreme weather events can have negative impacts on species survival and community structure when surpassinglethal thresholds. Extreme winter warming events in the Arctic rapidly melt snow and expose ecosystems to unseasonablywarm air (2–10 °C for 2–14 days), but returning to cold winter climate exposes the ecosystem to lowertemperatures by the loss of insulating snow. Soil animals, which play an integral part in soil processes, may bevery susceptible to such events depending on the intensity of soil warming and low temperatures following theseevents. We simulated week-long extreme winter warming events – using infrared heating lamps, alone or with soilwarming cables – for two consecutive years in a sub-Arctic dwarf shrub heathland. Minimum temperatures werelower and freeze-thaw cycles were 2–11 times more frequent in treatment plots compared with control plots. Followingthe second event, Acari populations decreased by 39%; primarily driven by declines of Prostigmata (69%)and the Mesostigmatic nymphs (74%). A community-weighted vertical stratification shift occurred from smallersoil dwelling (eu-edaphic) Collembola species dominance to larger litter dwelling (hemi-edaphic) species dominancein the canopy-with-soil warming plots compared with controls. The most susceptible groups to these winter warming events were the smallest individuals (Prostigmata and eu-edaphic Collembola). This was not apparent from abundance data at the Collembola taxon level, indicating that life forms and species traits play a major role in community assembly following extreme events. The observed shift in soil community can cascade down to the micro-flora affecting plant productivity and mineralization rates. Short-term extreme weather events have the potential to shift community composition through trait composition with potentially large consequences for ecosystem development.

In the present study the induction of metallothioneins (MTs) and effects on the cellular energy allocation (CEA) in euryhaline crustacean Neomysis integer exposed to Cd at different salinities were studied. N. integer was exposed to the same sub-lethal concentration of free cadmium ion (1/5 of the cadmium activity of the reported 96 h LC50 value) in hypo-osmotic (7.2 µg Cd/L at 5 psu), isosmotic (23.0 µg Cd/L at 16 psu) and hyper-osmotic media (38.1 µg Cd/L at 25 psu) for 7 days. By using the free Cd concentration as the basis for conducting the exposures, the effect of salinity on cadmium speciation was eliminated and therefore the true effect of salinity as an abiotic factor on the MT induction and CEA could be studied. MT content was quantified by differential pulse voltammetry (DPV); this is the first time that this method is applied to assays with N. integer. No significant differences in MT levels between the control and Cd-exposed groups were observed. The measured MT levels (ranging from 32.3 to 75.7 µg/mg(cytosolicprotein) probably represent the constitutive MT levels responsible for binding essential metals. The differences in MT levels observed at the different salinities indicate a possible relationship between some physiological process (possibly osmoregulation) other than detoxification and MT induction. A decrease in salinity caused an increase in MT level in N. integer, and this was significantly correlated to the CEA values (Spearman correlation coefficient r=-0.56,p= 0.016). Our results indicate that salinity can change the energy status and MT content of N integer. These findings should be taken into account when using these biomarkers - and especially MTs - in field studies and environmental monitoring.

In the present study the induction of metallothioneins (MTs) and its relation to cytosolic metal concentrations (Zn, Cu and Cd) in the euryhaline crustacean Neomysis integer exposed to Cd at different salinities was studied. N. integer was exposed to the same free cadmium ion activity of 5.74 x — 10-9 mol l-1 (i.e. 1/5 of the 96 h LC50 value expressed as cadmium activity) in hypo-osmotic (5 psu), isosmotic (16 psu) and hyper-osmotic media (25 psu) for 7 days. In this way, the effect of salinity on cadmium speciation was eliminated and therefore the physiological effect of salinity on Cd accumulation and MT induction could be studied. The accumulation of cytosolic Cd in N. integer changed with salinity from 1.11 ± 0.05 µmol l -1 at 5 psu up to 1.43 ± 0.17 µmol l-1 at 25 psu. This could indicate that the physiological response of euryhaline estuarine invertebrates like N. integer to salinity changes can influence the rate of trace metal uptake from solution. While the salinity changes did not cause significant differences in cytosolic Zn concentrations (mean value of all tested salinities: 34.4 ± 2.8 µmol l-1), an inverse relationship between salinity and cytosolic Cu concentration was observed. The highest concentration of 15.7 ± 2.3 µmol Cu l-1 was determined at 5 psu and the lowest 10.9 ± 1.4 µmol Cu l-1 at 25 psu. This could point to a possible relationship between the copper concentration and the hemocyanin metabolism in N. integer. This is the first time that differential pulse voltammetry method was applied to MT assays with N. integer. Although the exposure to Cd resulted in a higher Cd cytosolic concentration, no subsequent MT increase was detected. The significant positive correlation between MT levels and cytosolic Cu concentrations (Spearman correlation coefficient rs = 0.356, p = 0.009) implies a strong relationship between MT and Cu in N. integer.

A highly spinose fragment of a possibly raptorial appendage from the Arenig (Early Ordovician) of the Upper Fezouata Formation north of Zagora, southeastern Morocco is described as the arthropod Pseudoangustidontus duplospineus gen. et sp. nov. The single fragmentary specimen displays a unique morphology, carrying at least 39 pairs of spines (i.e., 78 spines) of very regularly alternating lengths. Pseudoangustidontus gen. nov. shows some similarities to a number of spinose arthropod appendages and appendage parts, most notably to the spine-bearing podomeres of the third prosomal appendage of megalograptid eurypterids and the problematic and incompletely known genus Angustidon tits. However, megalograptids and Angustidontus both have a lower spine count, while the latter also carries only a single row of spines. Because no known arthropod displays a morphology closely comparable to that of Pseudoangustidontus gen. nov., the affinities of the new fossil within Arthropoda remain uncertain.

Regulatory assessments of metals in freshwaters are mostly based on dissolved metal concentrations, assuming that toxicity is caused by waterborne metal only. Little attention has been directed to the toxicity of dietary metals to freshwater invertebrates. In this study the chronic toxicity of dietary zinc to Daphnia magna was investigated. The green alga Pseudokirchneriella subcapitata was exposed for 64 h to a control and three dissolved zinc concentrations, i.e. 23, 28 and 61 µg L-1, resulting in internal zinc burdens in the algae of 130, 200, 320 and 490 µg g-1 dry weight, respectively. These algae were used as a food source in chronic, 21-day bioassays with D. magna in a test medium to which no dissolved zinc was added. None of the treatments resulted in effects on feeding rates or somatic growth of D. magna. In contrast, a significant 40% decrease of total reproduction (number of juveniles per adult) was observed in the 28 and 61 µg L-1 treatments. Time to first brood was not affected, whereas the mean brood size and the fraction of reproducing parent daphnids were reduced from the second brood onwards and the magnitude of these reductions increased with each subsequent brood. The reduced reproduction was accompanied with an elevated zinc accumulation in the 61 µg L-1 treatment only, suggesting that total body burden is no good indicator of dietary zinc toxicity. Overall our data suggest that dietary zinc specifically targets reproduction in D. magna through accumulation in particular target sites, possibly cells or tissues where vitellogenin synthesis or processing occur. Further, our data illustrate that the potential importance of the dietary exposure route should be carefully considered and interpreted in regulatory assessments of zinc.

During recent years nearly 500 samples from boreholes drilled in West Flanders have been analyzed (figs 1-3). These samples appeared to contain sufficient amounts of bioclasts (1-2.4 mm) to allow a subdivision into ecozones, which formed the basis of a lithostratigraphic subdivision (fig. 4). The bioclast assemblages indicate that these boreholes are situated outside the depositional area of the Campine-Limburg basin (Maastricht-Hasselt-Antwerp). That is the reason why Arabic numerals have been used in the ecozonation, in distinction with the ecozonation of the Campine-Limburg basin (Roman numerals, fig.5). In the boreholes examined Cretaceous rests directly either on Cambro-Silurian of the Brabant Massif or on the Devono-Carboniferous of the Tournai Basin (Namur Synclinorium), north of the Bordière Fault. A limited number of samples from the Mons basin (Fig.6) appear to indicate that the West Flanders samples are more closely correspond with strata of that basin. The Nevele and Dendermonde boreholes (East Flanders) cannot directly be tied in with the ecozones. The Nevele samples may belong to ecozones 4 and 5. The Dendermonde borehole is characterized by a different bioclast assemblage and thus cannot be correlated with boreholes.Bioclast cannot be used for age determination of strata, which is why other methods are necessary. In the present case we have relied on the studies carried out by F. Robaszynski 1989 and S. Louwye 1993.

Cryptalgal-bryozoan carbonate buildups are reported from the Middle Visean (Upper Dinantian) near Namur, Belgium. They occur in a 20 m-thick, upward-shallowing, carbonate rhythm - the thickest in a succession of such rhythms.The rhythm comprises three phases; from bottom to top: (1) packstones-grainstones with rich and diverse biota, indicating open, shallow marine conditions; grading to (2) wackestones, with a poorer and more restricted biota, passing upwards to cryptalgal boundstones; and(3) mudstones with highly restricted and reduced biota.Small- to medium- sized mounds (2-11 m thick) occur at the top of Phase 2 where they established on coral thickets. The buildups consist of a meshwork of bryozoans encrusted by finely laminated cryptalgal coatings and encrusting bryozoans. Brachiopods, sponges and vermetid gastropods are also present. Voids were filled by internal sediments and early marine cements. The growth of the buildups was probably interrupted by a short-lived sea-level drop, recorded laterally as what seems to be a karstic surface. Vadose internal sedimentation and minor leaching by meteoric water occurred in the ?exposed buildups. Marine conditions were then restored and, at the beginning of Phase 3 deposition, coral thickets (with cryptalgal coatings) colonized the top of the largest buildup. Most remaining pore space was filled by burial cements. Other minor diagenetic processes include neomorphism, dolomitization, precipitation of Ca-sulphates and silicification.

This is the first checklist of the Belgian species of marine and brackish-water Isopoda. The list is an up-to-date revision of the study of Holthuis (1950). Many species of this study had to be omitted as Holthuis included data from a considerable part of the southern North Sea and from the eastern entrance of the Channel. Recently some additions to the Belgian fauna have been made.

The sedimentological study of the Frasnian Tapoumont red marble bioherm (Philippeville antiform, Belgium, «F2j» based on rugose corals) enables recognition of twelve microfacies. They range from sponge spicule mudstones to crinoidal, coral rudstones. Water agitation and light supply normally control the bioherm growth, but three environments do not follow the rule. They are characterized by the abundance of microorganic mats, now in form of irregular plurimetric fenestrae. cemented by radiaxial calcite. They are more and more abundant towards the centre of the buildup. Four lateral microfacies are studied. The bioherm geometry is discussed, and a weak sedimentary slope is proposed.

The Huy formation («assise de Huy») is the oldest unit present in outcrops in the Belgian «Bande de Sambre-et-Meuse». Graptolites and acritarchs show that the beds are of early Llanvirn Didymograptus artus Biozone age. The localities of Huy and of Sart-Bernard and the Wépion borehole are reinvestigated and the collection of Maillieux, 1939 is restudied.