A Forgotten Chiral Spiro Compound Revisited: 3,3'‐Dimethyl‐3H,3'H‐2,2'‐spirobi[[1,3]benzothiazole]

The title compound was obtained as a side product during dimerization‐oxidation steps of the carbene generated from N‐methylbenzothiazolium iodide. Chromatography on (S,S)‐Whelk O1 column showed on cooling a typical plateau shape chromatogram indicating an exchange between two enantiomers on the column. The thermal barrier to racemization was determined (85 kJ.mol^?1 at 10 °C) by dynamic high‐performance liquid chromatography (DHPLC).The absolute configuration of the first (M) and second eluted (P) enantiomers on the (S, S)‐Whelk O1 column was established by comparing the reconstructed circular dichroism (CD) spectra from the CD detector signal and the calculated CD spectrum of the (P) enantiomer. Mass spectrometry revealed that 3,3'‐dimethyl‐3H,3'H‐2,2'‐spirobi[[1,3]benzothiazole] can be viewed as a masked thiophenate attached to a benzothiazolium framework. Chirality 27:716–721, 2015. © 2015 Wiley Periodicals, Inc.     

Length–weight relationships of 14 coastal fish species from Punta del Diablo (Rocha,Uruguay)

This study provides information on length‐weight relationships for 14 marine fish species. Specimens were collected between 2006 and 2010 from the Uruguayan coastal zone (depth < 15 m) in Punta del Diablo, Rocha during a biodiversity monitoring program. This study represents the first reference on length‐weight relationships for two endangered Rajidae species and confirms the presence of the Stellifer rastrifer, whose distribution range has been extended southwards recently.     

Enantioresolution of Chiral Derivatives of Xanthones on (S,S)‐Whelk‐O1 and l‐Phenylglycine Stationary Phases and Chiral Recognition Mechanism by Docking Approach for (S,S)‐Whelk‐O1

The resolution of seven enantiomeric pairs of chiral derivatives of xanthones (CDXs) on (S,S)‐Whelk‐O1 and l ‐phenylglycine chiral stationary phases (CSPs) was systematically investigated using multimodal elution conditions (normal‐phase, polar‐organic, and reversed‐phase). The (S,S)‐Whelk‐O1 CSP, under polar‐organic conditions, demonstrated a very good power of resolution for the CDXs possessing an aromatic moiety linked to the stereogenic center with separation factor and resolution factor ranging from 1.91 to 7.55 and from 6.71 to 24.16, respectively. The chiral recognition mechanisms were also investigated for (S,S)‐Whelk‐O1 CSP by molecular docking technique. Data regarding the CSP–CDX molecular conformations and interactions were retrieved. These results were in accordance with the experimental chromatographic parameters regarding enantioselectivity and enantiomer elution order. The results of the present study fulfilled the initial objectives of enantioselective studies of CDXs and elucidation of intermolecular CSP–CDX interactions. Chirality 25:89–100, 2013. © 2012 Wiley Periodicals, Inc.     

Form and Function in the Xenarthra–an Introduction to the Symposium Proceedings Volume

This special issue of the Journal of Mammalian Evolution represents the proceedings from a symposium held in conjunction with the 9th International Congress of Vertebrate Morphology (ICVM IX, Punta del Este, Uruguay, July 29, 2010), and entitled “Form and Function in the Xenarthra.” This symposium was the third on xenarthran biology to be presented in association with the ICVM meetings. In this brief introduction to the symposium proceedings, we plan to discuss the justification for the symposium, to provide a brief history of previous symposia and their results, and to introduce the contents of the present volume.     

Food habits of the silky shark Carcharhinus falciformis (Müller & Henle, 1839) off the western coast of Baja California Sur,Mexico

The objective of this study was to establish the trophic niche of the silky shark and to determine the ecological role of this predator in the ecosystem close to Baja California. The trophic spectrum was analyzed from samples taken during summer and autumn (2000–2002) from the fishing camps of Punta Lobos and Punta Belcher on the western coast of Baja California Sur. A total of 263 stomach contents were analyzed (143 with food; 120 empty). The index of relative importance (IRI) showed that at Punta Lobos, silky sharks fed mainly on red crabs Pleuroncodes planipes (%IRI = 83%), whereas at Punta Belcher the main food item was the jumbo squid Dosidicus gigas (%IRI = 41%), followed by chub mackerel Scomber japonicus (%IRI = 33%). According to the Levin Index (Bi), the trophic niche breadth in silky sharks is low (Bi = <0.6), which means that silky sharks are specialist predators because they mainly consume three prey types: red crab, chub mackerel, and jumbo squid. The Shannon‐Wiener Index indicated that all trophic categories at Punta Belcher (0.85–1.22) had lower diversity than at Punta Lobos (0.50–1.6), because the silky shark feeds more on tropical prey found close to Punta Lobos. The Morisita‐Horn Index (Cλ) showed an overlap in the diet between the two areas analyzed and between sexes (Cλ = >0.6). The juveniles and adult females did not show any overlap. In the caloric analysis of the main prey, the jumbo squid (D. gigas) contributed the most calories to the silky shark diet (76%).     

Vagrant Antarctic fur seals, Arctocephalus gazella, in southern Chile

The Antarctic fur seal, Arctocephalus gazella, in the eastern South Pacific Ocean, first reported on Hoste Island, Cape Horn in 1973, and then on the Juan Fernandez Archipelago in 1982 and 1983, was recorded again in October and December 2009 on the southern coast of Chile. Three different individuals were seen simultaneously on a single day at Punta Dungenes, Magellan Strait, and a fourth individual was sighted at the northeastern coast of Almirantazgo Sound, Tierra del Fuego. These records represent the first sightings of live Arctocephalus gazella in southern Chile. Although it is difficult to establish both their origin and rationale for dispersion outside of their distribution range, the substantial breeding population recovery in South Georgia and food shortages during the breeding and post-breeding season are suggested as possible explanations.     

Microsatellite Evidence for High Frequency of Multiple Paternity in the Marine Gastropod Rapana venosa

Background

Inferring of parentage in natural populations is important in understanding the mating systems of a species, which have great effects on its genetic structure and evolution. Muricidae, a large group (approximately 1,600 species) of marine gastropods, are poorly investigated in patterns of multiple paternity and sperm competition based on molecular techniques. The veined Rapa whelk, Rapana venosa, a commercially important muricid species with internal fertilization, is an ideal species to study the occurrence and frequency of multiple paternity and to facilitate understanding of their reproductive strategies.

Methodology/Principal Findings

We developed five highly polymorphic microsatellites in R. venosa and applied them to identify multiple paternity in 19 broods (1381 embryos) collected from Dandong, China. Multiple paternity was detected in 17 (89.5%) of 19 broods. The number of sires per brood ranged from 1 to 7 (4.3 on average). Of the 17 multiply sired broods, 16 (94.1%) were significantly skewed from equal paternal contributions, and had a dominant sire which was also dominant in each assayed capsule.

Conclusions

Our results indicate that a high level of multiple paternity occurs in the wild population of R. venosa. Similar patterns of multiple paternity in the 2–6 assayed capsules from each brood imply that fertilization events within the body of a female occur mostly (but not entirely) as random draws from a “well-but-not-perfectly blended sperm pool” of her several mates. Strongly skewed distributions of fertilization success among sires also suggest that sperm competition and/or cryptic female choice might be important for post-copulatory paternity biasing in this species.     

Genetically monomorphic invasive populations of the rapa whelk,Rapana venosa

Rapana venosa is a predatory marine gastropod native to the coastal waters of China, Korea, and Japan. Since the 1940s, R. venosa has been transported around the globe and introduced populations now exist in the Black Sea, the Mediterranean Sea, the Adriatic and Aegean seas, off the coasts of France and the Netherlands, in Chesapeake Bay, Virginia, USA, and in the Rio de la Plata between Uruguay and Argentina. This study surveyed variation in two mitochondrial gene regions to investigate the invasion pathways of R. venosa, identify likely sources for introduced populations, and evaluate current hypotheses of potential transportation vectors. Sequence data were obtained for the mitochondrial cytochrome c oxidase I and NADH dehydrogenase subunit 2 gene regions of 178 individuals from eight native locations and 106 individuals from 12 introduced locations. Collections from within the native range displayed very high levels of genetic variation while collections from all introduced populations showed a complete lack of genetic diversity; a single haplotype was common to all introduced individuals. This finding is consistent with the hypothesis that R. venosa was initially introduced into the Black Sea, and this Black Sea population then served as a source for the other secondary invasions by various introduction vectors including ballast water transport. Although non‐native R. venosa populations currently appear to be thriving in their new environments, the lack of genetic variability raises questions regarding the evolutionary persistence of these populations.     

Lack of Ecotypic Differentiation: Plant Response to Elevation,Population Origin,and Wind in the Luquillo Mountains,Puerto Rico1

How important is ecotypic differentiation along elevational gradients in the tropics? Reciprocal transplants of two shrubs, Clibadium erosum (Asteraceae) and Psychotria berteriana (Rubiaceae), and a palm, Preitoea acuminata var. montana (Palmaceae), were used to test for the effect of environment and population origin on growth and physiology in the Luquillo Experimental Forest of Puerto Rico. Two sites were used, one at Pico del Este (1000 m in cloud forest) and one at El Verde (350 m in lower montane rain forest). At the cloud forest site, plastic barriers were erected around a subset of the plants to examine if protection from wind affected survival or biomass accumulation. Survival of C. erosum and P. berteriana was not affected by site, population origin, or the presence of barriers. For P. acuminata var. montana, survival was higher for plants with barriers, but not affected by site and population origin. Plants of C. erosum and P. berteriana at El Verde grew larger than at Pico del Este, but there was no effect of population origin or barrier treatment on biomass accumulation for these species. For P. acuminata var. montana, there was no effect of environment, population origin, or barrier treatment on biomass accumulation. Light‐saturated photosynthetic rate (A_max) of C. erosum, P. berteriana, and P. acuminata var. montana, as well as leaf anatomical characteristics of C. erosum, were unaffected by environment, population origin, and barrier treatment. On balance, there seems to be little evidence of ecotypic differentiation in these species along the gradient.     

A New Freshwater Naked Lobose Amoeba Korotnevella venosa n. sp. (Amoebozoa,Discosea)

A new freshwater species of naked lobose amoebae Korotnevella venosa n. sp. isolated from freshwater pond in St. Petersburg, Russia was studied with light and transmission electron microscopy. Basket scales of this species have six vertical columns supporting perforated rim. The latter has tongue‐like broadening with membranous region. Vertical columns bifurcate at both ends so that neighboring columns are connected by their bifurcations forming combined structure. Basket scales of K. venosa are similar to those of Korotnevella hemistylolepis in having six full‐length vertical columns and perforated rim. At the same time, they are different in having tongue‐like broadening of perforated rim with membranous region and absence of six half‐length columns and an intermediate crosspiece. Phylogenetic trees based on 18S rDNA gene placed K. venosa either at the base of the whole Korotnevella clade, next to K. hemistylolepis, or as a sister to the clade comprising Korotnevella species with latticework basket in large scales.     

Impacts of two invasive mollusks, <Emphasis Type="Italic">Rapana venosa</Emphasis> (Gastropoda) and <Emphasis Type="Italic">Corbicula fluminea</Emphasis> (Bivalvia), on the food web structure of the Río de la Plata estuary and nearshore oceanic ecosystem

This paper quantifies the impacts of two invasive species, Rapana venosa (Gastropoda, Muricidae) and Corbicula fluminea (Bivalvia, Corbiculidae), in the food web of the Río de la Plata estuary and adjacent nearshore oceanic ecosystem. We analyzed certain functional traits of these mollusks assessed by a mass balance trophic model previously constructed for the years 2005–2007. This model incorporates 37 functional groups: three marine mammals species, one coastal bird, 17 fishes, 12 invertebrates, two zooplankton, one phytoplankton, and detritus. The model also includes 5 fishing fleets operating in the area. The results showed that the two invasive species affect multiple ecosystem components both directly and indirectly. R. venosa and the whitemouth croaker, Micropogonias furnieri, exhibited a high level of niche overlap (91%), while C. fluminea exhibited a high level of niche overlap with Mytilidae (94%), which suggests in both cases high levels of competition for similar resources. R. venosa had mixed trophic impacts but exhibited a predominantly top down effect on most bivalves. R. venosa could be a threat to natural resources in the area including to the fishing fleets. C. fluminea negatively influenced phytoplankton and detritus biomass and its positive effects on higher trophic level groups suggest a central bottom-up role in the food web as a bentho-pelagic coupler. Both species had negative impacts on the five fleets modeled, showing that the effects of these invasive species could extend to the socio-economic sector.     

Amino Acids from <Emphasis Type="Italic">Mytilus galloprovincialis</Emphasis> (L.) and <Emphasis Type="Italic">Rapana venosa</Emphasis> Molluscs Accelerate Skin Wounds Healing via Enhancement of Dermal and Epidermal Neoformation

Wound healing consists of re-epithelialization, contraction and formation of granulation and scar tissue. Amino acids from proteins are involved in these events, but their exact roles are not well understood. The present study was undertaken to investigate the anti-inflammatory effects of some amino acids from two molluscs, Mytilus galloprovincialis (L.) (Mediterranean mussel) and Rapana venosa (hard shell-clam) employed in induced skin burn injuries in Wistar rats. The treatment was evaluated in terms of essential amino acids composition which rendered the extracts very efficient in healing skin burns. The healing process was examined by periodic acid Schiff’s, Verhoeff’s Van Gieson and immunohistochemistry stains for collagen IV, CD 34 and CD 117 antibodies. According to the obtained results, as expressed by histological studies, the most abundant blood vessels, collagen fibres, basal and stem cells were found only for treated animals with amino acids from Rapana venosa extracts. The rich composition of amino acids from the two molluscs merits consideration as therapeutic agents in the treatment of skin burns.     

Consumption rates and prey preference of the invasive gastropod Rapana venosa in the Northern Adriatic Sea

The alien Asian gastropod Rapana venosa (Valenciennes 1846) was first recorded in 1973 along the Italian coast of the Northern Adriatic Sea. Recently, this predator of bivalves has been spreading all around the world oceans, probably helped by ship traffic and aquaculture trade. A caging experiment in natural environment was performed during the summer of 2002 in Cesenatico (Emilia-Romagna, Italy) in order to estimate consumption rates and prey preference of R. venosa. The prey items chosen were the Mediterranean mussel Mytilus galloprovincialis (Lamarck 1819), the introduced carpet clam Tapes philippinarum (Adams and Reeve 1850), both supporting the local fisheries, and the Indo-Pacific invasive clam Anadara (Scapharca) inaequivalvis (Bruguière 1789). Results showed an average consumption of about 1 bivalve prey per day (or 1.2 g wet weight per day). Predation was species and size selective towards small specimens of A. inaequivalvis; consumption of the two commercial species was lower. These results might reduce the concern about the economical impact on the local bivalve fishery due to the presence of the predatory gastropod. On the other hand, selective predation might probably alter local community structure, influencing competition amongst filter feeder/suspension feeder bivalve species and causing long-term ecological impact. The large availability of food resource and the habitat characteristics of the Emilia-Romagna littoral makes this area an important breeding ground for R. venosa in the Mediterranean Sea, thus worthy of consideration in order to understand the bioinvasion ecology of this species and to control its likely further dispersal.     

Resolution,determination of enantiomeric purity and chiral recognition mechanism of new xanthone derivatives on (S,S)‐whelk‐O1 stationary phase

The enantioresolution and determination of the enantiomeric purity of 32 new xanthone derivatives, synthesized in enantiomerically pure form, were investigated on (S ,S )‐Whelk‐O1 chiral stationary phase (CSP). Enantioselectivity and resolution (α and R_S) with values ranging from 1.41–6.25 and from 1.29–17.20, respectively, were achieved. The elution was in polar organic mode with acetonitrile/methanol (50:50 v/v ) as mobile phase and, generally, the (R )‐enantiomer was the first to elute. The enantiomeric excess (ee ) for all synthesized xanthone derivatives was higher than 99%. All the enantiomeric pairs were enantioseparated, even those without an aromatic moiety linked to the stereogenic center. Computational studies for molecular docking were carried out to perform a qualitative analysis of the enantioresolution and to explore the chiral recognition mechanisms. The in silico results were consistent with the chromatographic parameters and elution orders. The interactions between the CSP and the xanthone derivatives involved in the chromatographic enantioseparation were elucidated.     

Marine algae from the Gulf of Santa Clara,Sonora, México

Four sites in the Gulf of Santa Clara, northwestern coast of Sonora, Mexico, were sampled seasonally during 1995–1996. A total of 43 species of marine algae were determined, which are recorded for the first time for the area of study. The families with best representation are: Gracilariaceae and Cladophoraceae, each with 5 species; and Corallinaceae, Rhodomelaceae, and Ulvaceae, each with 3. The highest diversity was found in autumn, the lowest in summer. The sites with the low diversity were Piedras del Burro with 7 species and El Tornillal with 18. These places are broad beaches, composed of sand and with few pebbles. The higher diversity was found at Punta Gorda with 34 species and Piedras de La Salina with 26. These localities are characterized by relatively stable rocky substrates, with some intertidal pools. The most common species regardless to distribution and occurrence over time were: Spyridia filamentosa, Dictyota flabellata, Struveopsis robusta, Cladophora microcladioides and Enteromorpha linza. Rosenvingea antillarum and Cladophora vagabunda represent new records for the Gulf of California. Nine epiphytic species were identified, which were frequently observed on Gelidium crinale, Spyridia filamentosa and Dictyota flabellata.     

Nutrient and salt relations of <Emphasis Type="Italic">Pterocarpus officinalis</Emphasis> L. in coastal wetlands of the Caribbean: assessment through leaf and soil analyses

Pterocarpus officinalis L. is a dominant tree of freshwater coastal wetlands in the Caribbean and the Guiana regions. It is frequently associated with mangroves in areas with high rainfall and/or surface run-off. We hypothesized that P. officinalis is a freshwater swamp species that when occurring in association with mangroves occupies low-salinity soil microsites, or alternatively that it possesses mechanisms preventing accumulation of salt in photosynthetic tissues. To test this we compared the mineral composition of soils and leaves of several species in two Pterocarpus forests in Puerto Rico associated with coastal mangroves, Sabana Seca and Punta Viento. Results indicate that (1) Sabana Seca has low soil salinity values even in the P. officinalis and Laguncularia racemosa mixed zone. In Punta Viento, salinity in the mixed zone was higher than in the Pterocarpus forest, but much lower than in the mangrove area; (2) In both forests, leaves of P. officinalis showed much lower Na concentrations than mangrove species. The K/Na ratios were 16–20 times higher in P. officinalis, indicating preferential absorption of K against Na. The mangrove fern (Acrostichum aureum) growing side by side with P. officinalis and L. racemosa in Punta Viento also revealed high Na exclusion capacity. We found an asymmetric distribution of cations in the blade and rachis of the P. officinalis compound leaves in both sites. The rachis accumulates more Na and Ca, but less Mg than the leaf blade. This sequestration of Na in the rachis prevents salt damage of photosynthetic tissue in the leaf blade.     

Characterisation of two South American food and medicinal plants by chemometric methods based on their multielemental composition

Introduction – The chemometric characterisation of two plants frequently used as food and medicinal species, Achyrocline satureioides and Achyrocline venosa (Asteraceae: Gnaphalieae), was carried out based on their mineral composition. Both species, known by the common name of ‘marcelas’, are very similar in their morphological features but they have different medicinal and food properties. Objective – To develop multivariate models for the classification of A. satureiodes and A. venosa based on their mineral content. Methodology – The analytic determinations were made by means of inductively coupled plasma optical emission spectrometry from aerial parts of the plants. An internal standard was used to evaluate the accuracy in the sample treatment and the recovery of toxic elements was studied. The multivariate methods used include principal components analysis, cluster analysis and linear discriminant analysis. Results – Classification for both A. satureioides and A. venosa was successful in all cases using only four variables: aluminium, iron, magnesium and sulphur content. The concentrations of the following elements were determined: Al, As, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, La, Mg, Mn, Mo, Na, Ni, P, Pb, S, Sr, Ti, V, Y and Zn. Conclusions – This method is useful to identify both species in raw material in order to detect eventual errors of selection. Copyright © 2010 John Wiley & Sons, Ltd.     

Palynofacies associated to hyperpycnite deposits of the Miocene,Cabo Viamonte Beds,Austral Basin,Argentina

The Miocene deposits in the Punta Basílica locality, southernmost Argentina, are included within the Cabo Viamonte Beds, Cabo Domingo Group, in the Austral foreland basin of Tierra del Fuego province. The prograding clinoform systems were accumulated during a weak compressional tectonic regime that allowed the development of a narrow shelf. Paleoenvironmental reconstructions suggest that these clinoforms comprise two dominant architectural elements, channel-levee and lobe complexes, formed mainly by density hyperpycnal currents in outer shelf to depositional slope environments. The transitional and recurrent (vertical and lateral) alternation between sedimentary structures without rheologic boundaries associated with the co-occurrence of plant remains (Nothofagus) are diagnostic criteria for the recognition of hyperpycnites. This type of density flow typically transports large volumes of sediment and organic matter from proximal to deep-marine settings. Four palynofacies types were recognized in a cluster analysis. In general, the palynofacies show predominance of spores and pollen grains, tissues, cuticles, and spongy to fibrous amorphous organic matter (plant and/or freshwater to brackish algae derived), which reflect different positions within the depositional system (e.g., levee-channel and lobe deposits). The co-occurrence of inshore (Batiacasphaera spp., Lingulodinium sp.) with relatively more oceanic (Operculodinium centrocarpum, Spiniferites spp.) dinoflagellates is a strong indication that shallow-water assemblages have been displaced into deep-water settings. Due to the presence of Lingulodinium hemicystum (first appearance data: 23.0 Ma.) and Pentadinium laticinctum (last appearance data: 11.6 Ma.) an age not older than Miocene and not younger than the Serravallian/Tortorian boundary for the Punta Basílica section is proposed.