7 research outputs found
Redescription of Antipathes dichotoma Pallas, 1766 (Cnidaria: Anthozoa: Antipatharia)
The type species of the genus Antipathes, (A. dichotoma Pallas, 1766) is redescribed and a neotype is designated. Differences in the size and shape of the spines, and in the size and density of the polyps are considered key characters in separating related species
Revision of the Antipatharia (Cnidaria: Anthozoa). Part II. Schizopathidae
The family of antipatharian corals, Schizopathidae (Cnidaria: Anthozoa: Antipatharia), is revised. The family is characterized by polyps elongated in the direction of the axis and having a transverse diameter of 2 mm or more. Genera are recognized on the basis of morphological features of the corallum. Schizopathes Brook (type species: S. crassa Brook) has a simple, pinnate corallum with a hook-like holdfast for support in soft sediments. Bathypathes Brook (type species: B. patula Brook) is characterized by a simple pinnate corallum and a flat discoidal basal plate for attaching to a solid substrate. Parantipathes Brook (type species: Antipathes larix Esper) has a largely monopodial corallum with simple pinnules in six or more rows. Taxipathes Brook (type species: T. recta Brook) has a branched corallum and simple pinnules in four to eight rows. Lillipathes gen. nov. (type species: Antipathes lilliei Totton) has simple pinnules in four rows. Stauropathes gen. nov. (type species: S. staurocrada spec. nov.) is branched with simple, bilateral, subopposite pinnules. Abyssopathes gen. nov. (type species: Bathypathes lyra Brook) is monopodial with two rows of simple, lateral pinnules and one (sometimes multiple) row of simple or branched anterior pinnules. Dendrobathypathes gen. nov. (type species: D. grandis spec. nov.) has a branched, planar corallum with two rows of subpinnulated primary pinnules. Saropathes gen. nov. (type species: Bathypathes scoparia Totton) is monopodial to sparsely branched, with four rows of subpinnulated primary pinnules
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Toxicological Benchmarks for Wildlife
Ecological risks of environmental contaminants are evaluated by using a two-tiered process. In the first tier, a screening assessment is performed where concentrations of contaminants in the environment are compared to no observed adverse effects level (NOAEL)-based toxicological benchmarks. These benchmarks represent concentrations of chemicals (i.e., concentrations presumed to be nonhazardous to the biota) in environmental media (water, sediment, soil, food, etc.). While exceedance of these benchmarks does not indicate any particular level or type of risk, concentrations below the benchmarks should not result in significant effects. In practice, when contaminant concentrations in food or water resources are less than these toxicological benchmarks, the contaminants may be excluded from further consideration. However, if the concentration of a contaminant exceeds a benchmark, that contaminant should be retained as a contaminant of potential concern (COPC) and investigated further. The second tier in ecological risk assessment, the baseline ecological risk assessment, may use toxicological benchmarks as part of a weight-of-evidence approach (Suter 1993). Under this approach, based toxicological benchmarks are one of several lines of evidence used to support or refute the presence of ecological effects. Other sources of evidence include media toxicity tests, surveys of biota (abundance and diversity), measures of contaminant body burdens, and biomarkers. This report presents NOAEL- and lowest observed adverse effects level (LOAEL)-based toxicological benchmarks for assessment of effects of 85 chemicals on 9 representative mammalian wildlife species (short-tailed shrew, little brown bat, meadow vole, white-footed mouse, cottontail rabbit, mink, red fox, and whitetail deer) or 11 avian wildlife species (American robin, rough-winged swallow, American woodcock, wild turkey, belted kingfisher, great blue heron, barred owl, barn owl, Cooper's hawk, and red-tailed hawk, osprey) (scientific names for both the mammalian and avian species are presented in Appendix B). [In this document, NOAEL refers to both dose (mg contaminant per kg animal body weight per day) and concentration (mg contaminant per kg of food or L of drinking water)]. The 20 wildlife species were chosen because they are widely distributed and provide a representative range of body sizes and diets. The chemicals are some of those that occur at U.S. Department of Energy (DOE) waste sites. The NOAEL-based benchmarks presented in this report represent values believed to be nonhazardous for the listed wildlife species; LOAEL-based benchmarks represent threshold levels at which adverse effects are likely to become evident. These benchmarks consider contaminant exposure through oral ingestion of contaminated media only. Exposure through inhalation and/or direct dermal exposure are not considered in this report
The magnitude of global marine species diversity
Background: The question of how many marine species exist is important because it provides a metric for how much we do and do not know about life in the oceans. We have compiled the first register of the marine species of the world and used this baseline to estimate how many more species, partitioned among all major eukaryotic groups, may be discoveredResults: There are ~226,000 eukaryotic marine species described. More species were described in the past decade (~20,000) than in any previous one. The number of authors describing new species has been increasing at a faster rate than the number of new species described in the past six decades. We report that there are ~170,000 synonyms, that 58,000–72,000 species are collected but not yet described, and that 482,000–741,000 more species have yet to be sampled. Molecular methods may add tens of thousands of cryptic species. Thus, there may be 0.7–1.0 million marine species. Past rates of description of new species indicate there may be 0.5 ± 0.2 million marine species. On average 37% (median 31%) of species in over 100 recent field studies around the world might be new to science.Conclusions: Currently, between one-third and two-thirds of marine species may be undescribed, and previous estimates of there being well over one million marine species appear highly unlikely. More species than ever before are being described annually by an increasing number of authors. If the current trend continues, most species will be discovered this century