Positional‐Species Composition of Diacylglycerol Acetates from Mature Euonymus Seeds

The positional‐species composition (PSC) of 3‐acetyl‐1,2‐diacyl‐sn‐glycerols (AcDAGs) from the seeds of mature fruits of 14 species of the genus Euonymus L. was established. The residues of six major fatty acids (FAs), palmitic ( P ), stearic ( St ), hexadecenoic ( H ), octadecenoic ( O ), linoleic ( L ), and linolenic ( Ln ), were present in the AcDAGs. Here, we demonstrated that the profile of PSC of AcDAGs could serve as chemotaxonomic factor to divide euonymus species studied here into groups which completely correlate with the present day systematic of the genus. In particular, the Euonymus section greatly exceeded other sections of the Euonymus subgenus as well as the Kalonymus one in the total levels of AcDAGs positional species having one and two O residues and was characterized by significantly lesser concentrations of species with one and two L residues. Moreover, in seed, AcDAGs of almost all Euonymus species EF_L values were slightly higher than EF_O ones, but all EF_L and EF_O values were higher than 1.0, and therefore, it can be concluded that both FAs mainly esterified sn‐2‐position of the glycerol moiety and saturated FAs residues were always virtually absent in the sn‐2 position of Euonymus seed AcDAGs, as it is also the case in nearly all TAGs molecules of plant origin.     

Multi‐taxon and forest structure sampling for identification of indicators and monitoring of old‐growth forest

Abstract

The most commonly used old‐growth forest indicators are structural attributes; nevertheless, they do not necessarily represent the biodiversity value of old‐growth forests. The aim of this study is to analyse the relationships between species richness data of different taxa and structural indicators of old‐growth and to identify taxonomic/functional groups, species and structural attributes that may be used as indicators of old‐growth. To achieve this goal we sampled forest structure, vascular plants, lichens, bryophytes, fungi, saproxylic beetles and birds in mature and old‐growth stands in southern Italy. We calculated Spearman’s correlation coefficients between species richness data and structural attributes. Analyses of indicator species, co‐occurrences and two‐way clusters were performed on the multi‐taxonomic list. The group of vascular plants most significantly correlated with other groups in terms of species richness; furthermore, it displays the highest proportion of between‐group co‐occurrences. The resulting multi‐taxonomic list of potential indicators may serve as an effective means of detecting and monitoring forest ecosystems; however, for this goal, structure‐based indicators, such as forest structural attributes and vascular plant species composition, are of primary importance.     

Identifying potentially invasive non‐native marine and brackish water species for the Arabian Gulf and Sea of Oman

Invasive non‐native species (NNS) are internationally recognized as posing a serious threat to global biodiversity, economies and human health. The identification of invasive NNS is already established, those that may arrive in the future, their vectors and pathways of introduction and spread, and hotspots of invasion are important for a targeted approach to managing introductions and impacts at local, regional and global scales. The aim of this study was to identify which marine and brackish NNS are already present in marine systems of the northeastern Arabia area (Arabian Gulf and Sea of Oman) and of these which ones are potentially invasive, and which species have a high likelihood of being introduced in the future and negatively affect biodiversity. Overall, 136 NNS were identified, of which 56 are already present in the region and a further 80 were identified as likely to arrive in the future, including fish, tunicates, invertebrates, plants and protists. The Aquatic Species Invasiveness Screening Kit (AS‐ISK) was used to identify the risk of NNS being (or becoming) invasive within the region. Based on the AS‐ISK basic risk assessment (BRA) thresholds, 36 extant and 37 horizon species (53.7% of all species) were identified as high risk. When the impact of climate change on the overall assessment was considered, the combined risk score (BRA+CCA) increased for 38.2% of all species, suggesting higher risk under warmer conditions, including the highest‐risk horizon NNS the green crab Carcinus maenas, and the extant macro‐alga Hypnea musciformis. This is the first horizon‐scanning exercise for NNS in the region, thus providing a vital baseline for future management. The outcome of this study is the prioritization of NNS to inform decision‐making for the targeted monitoring and management in the region to prevent new bio‐invasions and to control existing species, including their potential for spread.     

Survey of the efficacy of a short fragment of the rbcL gene as a supplemental DNA barcode for diatoms

DNA barcoding is a tool that uses a short, standard segment of DNA to identify organisms. In diatoms, a consensus on an appropriate DNA barcode has not been reached, but several markers show promise. These include the 5.8S gene plus a fragment of the internal transcribed spacer 2 (ITS‐2) of nuclear‐encoded ribosomal RNA, a 420‐bp segment of the 18S rRNA gene, and a 748‐bp fragment at the 3′‐end of the ribulose bisophosphate carboxylase large subunit (rbcL) gene. Here, we tested a 540‐bp fragment 417‐bp downstream of the start codon of the rbcL gene for its efficacy in distinguishing diatom species in a wide range of taxa. Overall, 381 sequences representing 66 genera and 245 species from the classes Mediophyceae and Bacillariophyceae were examined. Intra/interspecific thresholds were set at p = 0.01 differences per site (diff./site) for Mediophyceae and p = 0.02 diff./site for Bacillariophyceae and correctly segregated 96% and 93% of morphological congeners, respectively. When testing reproductively isolated or biological species, which are only available from Bacillariophyceae, 80% of species were discriminated. Therefore, we concluded that, alone, the rbcL region tested herein as potential a DNA barcode was not a sufficient discriminator of all diatoms. We suggest that this fragment could be used in a dual‐locus barcode with the more variable 5.8S+ITS‐2 to discriminate species without sufficient interspecific divergences in the tested rbcL region and to provide insight into species identity from a separately evolved genome.     

Molecular data reveal a diverse Astyanax species complex in the upper Iguaçu River

Astyanax is among the most speciose genera in the Characidae. In this study, molecular markers were used to assess the extent to which some of the commonly recognized Astyanax species of the upper Iguaçu River correspond to natural groups. These results indicate that the diversity of Astyanax has been severely underestimated with several potential cryptic species.     

Polymorphic microsatellite DNA markers for the rhinoceros auklet (Cerorhinca monocerata)

Eight polymorphic microsatellite loci were isolated from the partial genomic library of the rhinoceros auklet Cerorhinca monocerata. The heterozygosities observed at the isolated loci using eight primer sets in 46 nestlings from one breeding colony in Japan ranged from 0.311 to 0.773, and all but one locus did not deviate from the Hardy–Weinberg expectations. Cross‐species amplification in the tufted puffin Fratercula cirrhata was successfully performed using six of the eight primer sets, indicating their applicability to this species.     

Eight questions about invasions and ecosystem functioning

I pose eight questions central to understanding how biological invasions affect ecosystems, assess progress towards answering those questions and suggest ways in which progress might be made. The questions concern the frequency with which invasions affect ecosystems; the circumstances under which ecosystem change is most likely; the functions that are most often affected by invaders; the relationships between changes to ecosystems, communities, and populations; the long-term responses of ecosystems to invasions; interactions between biological invasions and other anthropogenic activities and the difficulty of managing undesirable impacts of non-native species. Some questions have been answered satisfactorily, others require more data and thought, and others might benefit from being reformulated or abandoned. Actions that might speed progress include careful development of trait-based approaches; strategic collection and publication of new data, including more frequent publication of negative results; replacement of expert opinion with hard data where needed; careful consideration of whether questions really need to be answered, especially in cases where answers are being provided for managers and policy-makers; explicit attention to and testing of the domains of theories; integrating invasions better into an ecosystem context; and remembering that our predictive ability is limited and will remain so for the foreseeable future.     

Unravelling below-ground plant distributions: a real-time polymerase chain reaction method for quantifying species proportions in mixed root samples

Knowledge on below-ground plant distributions is almost lacking to date, despite the fact that such information would be very valuable in understanding below-ground competition and species-specific interactions, processes that are expected to shape community structure. Methods available so far for below-ground species determination have drawbacks that we tried to challenge. Some methods make use of differences in the chemical composition between species, but this is highly variable upon environmental factors. DNA-based techniques - far less dependent on chemical composition - such as polymerase chain reaction on internal transcribed spacer (ITS) primers can so far only determine presence-absence of a species in a mixed root sample. Here, we present a quantitative DNA-based technique that allows investigation of relative species abundances in experimental mixed root samples. We used quantitative real-time polymerase chain reaction (PCR) on species-specific markers obtained from intersimple sequence repeat (ISSR) analyses in root samples. This molecular technique is novel in the field of root ecology and its development overcame three challenges: (i) determination of species-specific DNA fragments, (ii) development and optimization of the real time PCR protocol, (iii) designing a data treatment method based on a modified delta-delta-cycle threshold (CT) analysis. The method gained robustness from using relative DNA abundances in species mixtures rather than absolute concentration readings. This requires accurate multispecies reference series as a calibration. Test samples with different known biomass ratios of all species showed proof of concept of this method. The pro's and contra's of this method are discussed in the light of its contribution to advancing ecological research on below-ground plant-plant interactions.     

Distribution and range expansion of deer in Ireland

• 1 Throughout Europe, the range of many deer species is expanding. We provide current distribution maps for red deer Cervus elaphus, sika Cervus nippon, fallow deer Dama dama and muntjac deer Muntiacus sp. in Ireland, and estimates of range expansion rates for red deer, sika and fallow deer.
• 2 There was a considerable expansion in the ranges of red deer, sika and fallow deer between 1978 and 2008. The compound annual rate of expansion was 7% for red deer, 5% for sika and 3% for fallow deer. The total range increase was 565% for red deer, 353% for sika and 174% for fallow deer. The potential implications of these expansions are discussed.
• 3 There are unknown numbers of red‐sika hybrid deer in some parts of Ireland. Range expansion is likely to lead to further hybridizations with implications for the genetic integrity of deer stocks.
• 4 Sightings of free‐roaming muntjac deer were first recorded in 2007. The distribution of confirmed sightings of single and multiple animals in the eastern region of Ireland suggests multiple releases.
• 5 Deer are already impacting on both the economic and biodiversity values of habitats in Ireland, where, at present, no sustainable deer management policy exists.

     

Changes in fish assemblages in catchments in north‐eastern Spain: biodiversity,conservation status and introduced species

1. North‐eastern Spain is a hot spot for the introduction of alien fish species, and its native fish fauna is one of the most endangered worldwide. We used an extensive data set from 2002 to 2003 and historical information from the area to characterize fish diversity and establish conservation priorities in river catchments. 2. Diversity indices were used to characterize fish diversity at the basin scale. An index of conservation status was applied for each species, which considers the occurrence, abundance and endemicity of each taxon. We used indirect ordination methods to test the relationship among basin features and to identify those variables most correlated with each other. To identify physical, biotic and environmental characteristics that seem to make a basin particularly susceptible to invasion, we performed a step‐wise multiple regression to examine the relationship between the number of native, translocated and introduced fish species (including the original native species richness of each basin), and landscape variables. 3. Over a period of approximately 50 years, the mean range size of native fish species has decreased by 60%. The greatest decline occurred in Gasterosteus gymnurus, Anguilla anguilla and Salaria fluviatilis, for which species over 75% of the original distribution area has been lost. The species with the highest conservation index were Gasterosteus gymnurus and Salaria fluviatilis. 4. Basin area and the catchment type explained 70% of variation in native species richness, whereas the number of dams and basin area accounted for more than 80% of variation in the number of introduced species. 5. The original native species richness and the number of introduced species at basin scale were not related, and thus there was no evidence of “biotic resistance” to invasion. The restoration of natural hydrologic processes and the development of specific management tools to protect native species, such as the prioritization of areas for fish conservation and the eradication of local populations of exotic species, are required to restore native fish fauna in these catchments.     

Macrocyprididae (Ostracoda) from the Southern Ocean: taxonomic revision,macroecological patterns,and biogeographical implications

Animal communities inhabiting shallow marine benthic environments around Antarctica are quite well known, however, only a few studies deal with the deep‐water faunas in the Southern Ocean. In the present study 19 deep‐water samples and 14 shallow and mid‐water samples containing macrocypridids were studied. The first important finding of the present study is the fivefold increase in the diversity of Macrocyprididae in the Southern Ocean: the species count increased from six to 30. Additionally, statistical analyses showed that depth is the main factor influencing macrocypridid assemblages and that geography does not play an important role. Two faunal bathymetric boundaries were observed, one around 1250 m and the other around 2500 m depth. Furthermore, species previously believed to be widely distributed (i.e. Macroscapha opaca, Macroscapha turbida, and Macroscapha inaequata) are shown to be groups of sometimes conspicuously distinct species. Over 30 Macrocyprididae species were identified from over 1200 specimens studied. After the study of the soft part morphology and chaetotaxy of Mh. opaca under the electron microscope, the following has been observed: (1) The exopodite of antenna II is clearly inserted on the distal margin of podomere II; (2) several setae previously considered aesthetascs (i.e. the long, proximal setae of podomere IV of the antenna II; the two sexually dimorphic setae of the podomere IV of antenna II; the modified setae of the podomeres II and III of the male appendage V) lack any pore, and should therefore not be chemoreceptors. Sixteen new species are described ( Macromckenziea giambonini sp. nov. , Macropyxis alanlordi sp. nov. , Macropyxis cronini sp. nov. , Macropyxis ghartmanni sp. nov. , Macropyxis hornei sp. nov. , Macropyxis jeans sp. nov. , Macropyxis parajeans sp. nov. , Macrosarisa andeep sp. nov. , Macrosarisa fahrbachi sp. nov. , Macroscapha cactus sp. nov. , Macroscapha falcis sp. nov. , Macroscapha rehmi sp. nov. , Macroscapha scotia sp. nov. , Macroscapha solecavai sp. nov. , Macroscapha subhemispherica sp. nov. , Macroscapha walterae sp. nov. ). Five previously described species are recorded: Macromckenziea glacierae Maddocks 1990 , Macroscapha inaequalis ( G. W. Müller, 1908 ), Mh. inaequata Maddocks 1990 , Mh. opaca Maddocks, 1990 species complex, Mh. turbida ( G. W. Müller, 1908 ). At least nine species are left in open nomenclature. Moreover, Yemanja gen. nov. is described from shallow tropical waters of the Western Atlantic; Macrosarisa procera ( Jellinek & Swanson, 2003 ) comb. nov. is proposed; and Macroscapha tensa ( Müller, 1908 ) is herein considered a nomen dubium. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 159 , 567–672.     

Reproductive compatibility among Mexican populations of Anastrepha obliqua: theoretical and management implications

The fraterculus species group, composed of 34 species in the genus Anastrepha (Diptera: Tephritidae), includes the fraterculus cryptic species complex formed by eight reproductively isolated morphotypes. A previous study revealed six genetic mitochondrial types of Anastrepha obliqua, suggesting the existence of a second cryptic species complex. However, marked discrepancies between nuclear and mitochondrial loci rather suggest incomplete lineage sorting or introgression between A. obliqua and A. fraterculus. Such hybridization could nevertheless result in reproductive isolation, an outcome that could affect efficacy of area‐wide management for the most important pest of mangos in America. Two mitochondrial types occur in Mexico, and the limits of a third one, encompassing Central American populations, have not been clearly established. Here, we tested reproductive compatibility among three A. obliqua populations from the Pacific and a population from the Gulf of Mexico. No evidence of pre‐zygotic isolation was found. Flies from the Atlantic mated randomly for equal duration with individuals from three Pacific populations. Homotypic and heterotypic crosses produced similar numbers of eggs, with heterotypic crosses of Pacific males and Atlantic females hatching in lower proportions. Larvae of all cross types developed equally in mangos and exhibited no sex ratio distortion of hybrid F1. The three mitochondrial types identified in Mexico and Central America do not appear to be cryptic species and can be managed using one single strain for the sterile insect technique.