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The sponge-dwelling snapping shrimps (Crustacea, Decapoda, Alpheidae, Synalpheus) of Discovery Bay, Jamaica, with descriptions of four new species

Smithsonian Libraries
Twenty-two species of sponge-dwelling shrimp in the genus Synalpheus were collected in the vicinity of Discovery Bay, Jamaica. Four of these species are new to science. Synalpheus thele n.sp., S. corallinus n. sp., and S. plumosetosus n. sp. belong to a group of morphologically similar species that also includes S. brooksi, S. bousfieldi, S. carpenteri, and S. chacei. Synalpheus irie n. sp. is a highly distinctive shrimp most similar to S. mcclendoni, but can be distinguished from the latter by the unique bowl-shaped fingers of the major chela and the two-pronged distal protuberance on the palm of the major chela. Synalpheus belizensis and S. regalis are reported for the first time from outside their type localities in Belize, while S. bocas and S. duffyi are reported for the first time outside their type localities in Caribbean Panama.

Degradation of 'Lumarith' Cellulose Acetate

Smithsonian Libraries
Objects manufactured from cellulose acetate comprise one of the most problematic groups of plastic in the collections of the Smithsonian Instititution's National Museum of American History (NMAH). To understand better cellulose acetate degradation, a 'salesman's sample kit' of 'Lumarith' brand, injection-molded, cellulose acetate color samples, manufactured by the Celluloid Company in the early twentieth century and now in the NMAH collection, was studied using minimally invasive analytical techniques at the Smithsonian Institution's Museum Conservation Institute (MCI). The kit includes 49 plastic coupons that vary in color, transparency, chemical composition and current state of degradation. Results of analysis were compared with Celluloid Company records at the NMAH Archives Center and Celanese Corporation in Narrows, Virginia, in order to determine the causes for their current level of preservation or degradation. The possible reasons for the degradation of some coupons are discussed; methods are proposed for identifying cellulose acetate objects that are at risk and for early detection of degradation.

Response to the Point of View of Gregory B. Pauly, David M. Hillis, and David C. Cannatella, by the Anuran Subcommittee of the Ssar/hl/asih Scientific and Standard English Names List

Smithsonian Libraries
The Point of View by Gregory Pauly, David Hillis, and David Cannatella misrepresents the motives and activities of the anuran subcommittee of the Scientific and Standard English Names Committee, contains a number of misleading statements, omits evidence and references to critical literature that have already rejected or superseded their positions, and cloaks the limitation of their nomenclatural approach in ambiguous language. Their Point of View is not about promoting transparency in the process of constucting the English Names list, assuring that its taxonomy is adequately reviewed, or promoting nomenclautural stability in any global sense. Rather, their Point of View focuses in larger part on a single publication, The Amphibian Tree of Life, which is formally unrelated to the Standard English Names List, and promotes an approach to nomenclauture mistakenly asserted by them to be compartible with both the International Code of Zoological Nomenclature and one of its competitros. the PhyloCode.

Is the Martian water table hidden from radar view?

Smithsonian Libraries
Mars may possess a global sub-surface groundwater table as an integral part of its current hydrological system. However, the Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) onboard the Mars Express (MEx) spacecraft has yet to make a definitive detection of such a body of liquid water. In this work, we quantify the conditions that would allow a detection of a deep aquifer and demonstrate that the lack of radar detection does not uniquely rule out the presence of such a body. Specifically, if the overlying crustal material has a conductivity above similar to 10(-5) S/m ( equivalent to a loss tanget of 0.008), a radar echo from an aquifer could be sufficiently attenuated by the intervening medium to prevent its detection by MARSIS. As such, the lack of direct detection by MARSIS-a "null result''-does not rule out the possibility of the water table's existence. Citation: Farrell, W. M., J. J. Plaut, S. A. Cummer, D. A. Gurnett, G. Picardi, T. R. Watters, and A. Safaeinili (2009), Is the Martian water table hidden from radar view?, Geophys. Res. Lett., 36, L15206, doi: 10.1029/2009GL038945.

Responses of Avicennia germinans (Black Mangrove) and the Soil Microbial Community to Nitrogen Addition in a Hypersaline Wetland

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The responses of dwarf black mangroves (Avicennia germinans) and components of the microbial community to the addition of nitrate over a 2-year period were examined. The field study was conducted in the Indian River Lagoon (Florida) in a mangrove-dominated impoundment that was established for purposes of mosquito control. The responses of mangroves to the regular addition of nitrate were insignificant or relatively minor compared to responses of the components of the microbial community. Denitrification rates, measured in the field and laboratory, increased significantly in fertilized plots and nitrous oxide emission rates were almost six times higher in fertilized plots. Nitrogen fixation was significantly lower in fertilized plots. Results suggest that mangrove systems in the N-limited Indian River Lagoon are likely to be long-term sinks for any increases in N loading.

Predicting declines in avian species richness under nonrandom patterns of habitat loss in a Neotropical landscape

Smithsonian Libraries
One of the key concerns in conservation is to document and predict the effects of habitat loss on species richness. To do this, the species-area relationship (SAR) is frequently used. That relationship assumes random patterns of habitat loss and species distributions. In nature, however, species distribution patterns are usually nonrandom, influenced by biotic and abiotic factors. Likewise, socioeconomic and environmental factors influence habitat loss and are not randomly distributed across landscapes. We used a recently developed SAR model that accounts for nonrandomness to predict rates of bird species loss in fragmented forests of the Panama Canal region, an area that was historically covered in forest but now has 53% forest cover. Predicted species loss was higher than that predicted by the standard SAR. Furthermore, a species loss threshold was evident when remaining forest cover declined by 25%. This level of forest cover corresponds to 40% of the historical forest cover, and our model predicts rapid species loss past that threshold. This study illustrates the importance of considering patterns of species distributions and realistic habitat loss scenarios to develop better estimates of losses in species richness. Forecasts of tropical biodiversity loss generated from simple species-area relationships may underestimate actual losses because nonrandom patterns of species distributions and habitat loss are probably not unique to the Panama Canal region.

Mating systems

Smithsonian Libraries

Plant d15N correlates with the transpiration efficiency of nitrogen acquisition in tropical trees

Smithsonian Libraries
Based upon considerations of a theoretical model of 15N/14N fractionation during steady-state nitrate uptake from soil (Comstock 2001, Planta 214:220-234), we hypothesized that, for plants grown in a common soil environment, whole plant {delta}15N ({delta}P) should vary as a function of the transpiration efficiency of nitrogen acquisition (FN/v) and the difference between whole-plant {delta}15N and root {delta}15N ({delta}P-{delta}R). We tested these hypotheses with measurements of several tropical tree and liana species. Consistent with theoretical expectations, both FN/v and {delta}P-{delta}R were significant sources of variation in {delta}P, and the relationship between {delta}P and FN/v differed between non-N2-fixing and N2-fixing species. We interpret the correlation between {delta}P and FN/v as resulting from variation in mineral nitrogen efflux to influx ratios across plasma membranes of root cells. These results provide a simple explanation of variation in {delta}15N of terrestrial plants, and have implications for understanding nitrogen cycling in ecosystems.

The cretaceous and paleocene Pleurotomariid (Gastropoda: Vetigastropoda) fauna of Seymour Island, Antarctica

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Leptomaria antipodensis and Leptomaria hickmanae are described from the Upper Cretaceous [Maastrichtian] Lopez de Bertodano Formation, Seymour Island, and represent the first Mesozoic records of the family Pleurotomariidae from Antarctica. Leptomaria stillwelli, L. seymourensis, Conotomaria sobralensis and C. bayeri, from the Paleocene [Danian], Sobral Formation, Seymour Island, are described as new. Leptomaria larseniana (Wilckens, 1911) new combination, also from the Sobral Formation, is redescribed based on better-preserved material. The limited diversity of the pleurotomariid fauna of Seymour Island is more similar to that of the Late Cretaceous faunas of Australia and New Zealand in terms of the number of genera and species, than to the older, more diverse faunas of South America, southern India, or northwestern Madagascar, supporting the status of the Weddelian Province as a distinct biogeographic unit. The increase in the species richness of this fauna during the Danian may be due to the final fragmentation of Gondwana during this period.

The contribution of epiphytes to the abundance and species richness of canopy insects in a Mexican coffee plantation

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The abundance of epiphytes has been assumed to be important in explaining the high diversity of tropical canopy arthropods. In this study we assessed the possible role that the presence of epiphytes may have on the diversity and abundance of canopy insects in an experimental study conducted in a coffee plantation in Coatepec, Veracruz, Mexico. Epiphytes were removed from trees in one of two plots in two sites of the coffee plantation. In each plot we collected insects from three Inga jinicuil trees by knockdown insecticide fogging. Insects were sorted to morphospecies. counted and measured. Trees with epiphytes had significantly higher numbers of species and individuals and insects larger than 5 mm were also more species-rich and abundant in trees with epiphytes. The magnitude of the enhancement was surprisingly large with the epiphyte plot samples having on average 90% more individuals and 22% more species than plots without epiphytes. These differences were even greater for large (> 5 mm) insects (184%, and 113% respectively). Our results support the tenet that epiphytes provide valuable resources to arthropods, which we have illustrated for canopy insects in shade trees of coffee plantations.
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