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The taxonomy of two trichodactyline genera of the Neotropical freshwater crab family Trichodactylidae are revised. The genus Avotrichodactylus Pretzmann, 1968, includes two species, A. constrictus (Pearse, 1911) and A. oaxensis Rodríguez, 1992; the genus Rodriguezia Bott, 1969, also has two species, R. mensabak Cottarelli andArgano, 1977, and R. villalobosi (Rodríguez andManrique, 1967). The taxonomic statuses of all the species are discussed and a short diagnosis is provided for each. A complete list of the material examined and a map of geographic distribution of the species are furnished.

Climate change, land-use change, pollution and exploitation are among the main drivers of species' population trends; however, their relative importance is much debated. We used a unique collection of over 1,000 local population time series in 22 communities across terrestrial, freshwater and marine realms within central Europe to compare the impacts of long-term temperature change and other environmental drivers from 1980 onwards. To disentangle different drivers, we related species' population trends to species- and driver-specific attributes, such as temperature and habitat preference or pollution tolerance. We found a consistent impact of temperature change on the local abundances of terrestrial species. Populations of warm-dwelling species increased more than those of cold-dwelling species. In contrast, impacts of temperature change on aquatic species' abundances were variable. Effects of temperature preference were more consistent in terrestrial communities than effects of habitat preference, suggesting that the impacts of temperature change have become widespread for recent changes in abundance within many terrestrial communities of central Europe.

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Abstract.  During two expeditions with RV ‘Meteor’ in summer 1993 and winter 1997/98 the structural and functional diversity of the benthic system of the highly oligotrophic eastern Mediterranean deep sea was investigated. The macrofauna communities were dominated by polychaetes even at the deepest stations. The fauna at shallow stations was dominated by surface deposit feeders, whereas subsurface deposit feeders and predators generally increased with depth. A high percentage of suspension‐feeding Porifera was found in the Levantine Basin. Mean abundance and number of taxa of both expeditions were significantly correlated to depth and distance to the nearest coast as well as to the total organic carbon (TOC) content in sediments. Numbers of taxa and abundance decreased generally with depth, although lowest numbers were not found at the deepest stations but in the extremely oligotrophic Levantine and Ierapetra Basin. Biomass measured during the second cruise was extremely low in the Ierapetra Basin and comparable to other extreme oligotrophic seas. The significant correlations found for TOC contents and macrofauna with distance to coast during both expeditions apparently reflect the role of hydrographically governed transport of organic matter produced in coastal regions into greater and extreme depths of the Mediterranean Sea. Seasonal differences in macrofauna communities due to seasonal differences in food supply were not found. However, recent large‐scale hydrographic changes (Eastern Mediterranean Transient, EMT) might change the oligotrophy and, thus, the structure of the benthic communities in the Eastern Mediterranean deep sea.

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Pinnotherids, or pea crabs, are symbionts of invertebrates used for shelter and as food source. Feeding strategies and morphological adaptations to food uptake are important to understand host relations and how the host specificity is determined. We herein re-examine the host range of pinnotherids based on long-term collections from different localities in European waters. Both species of Pinnotheres are restricted to bivalves. Pinnotheres pisum infests mussels, oysters, the noble pen shell Pinna nobilis and other bivalves. Pinnotheres pectunculi is symbiotic with Glycymeris glycymeris and several other species of venerids. Nepinnotheres pinnotheres infests ascidians and Pinna nobilis. Observations on feeding in Pinnotheres reveal how mucus strings are brushed from the host gills with a setal comb in the chelipeds, which we describe by using scanning electron microscopy. Our observations on feeding structures are discussed in relation to the host specificity of each species and compared to other pinnotherid taxa, taking additional factors of host choice into account.

Forensic taphonomy in the marine context recently received growing attention. However, only limited information is available about the fate of human bodies at greater sea depth. Following two fatal aircraft accidents (west of Namibia, south of Sicily) human remains were recovered from a depth of 540-580 m (both cases) after 3 months (Namibia)/34 days (Sicily). In the Namibia case fully skeletonized bones were lifted. In the Sicily case a complete, dressed body was found exhibiting a partially skeletonized skull, starting adipocere formation and pink teeth. The rate and mode of decomposition of human bodies in the deep sea varies considerably and is mainly influenced by the local faunal composition. Of special relevance for the understanding of both cases was the oceanographic observation that the highly efficient necrophageous lyssianassids are abundant off Namibia but are rare in the Mediterranean, emphasizing the importance of collaboration of forensic and marine scientists in such case work.