Taxonomic status

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The phylogenetic position and taxonomic status of Sterechinus bernasconiae Larrain, 1975 (Echinodermata, Echinoidea), an enigmatic Chilean sea urchin.

The phylogenetic position and taxonomic status of Sterechinus bernasconiae Larrain, 1975 (Echinodermata, Echinoidea), an enigmatic Chilean sea urchin.

In this context, S. bernasconiae has attracted our attention as it is the only species of Sterechinus reported from the Pacific Ocean. It is recorded from a narrow area off the coast of southern Chile. In contrast, S. agassizi is much more widely distributed on the Atlantic side of southern South America; it extends from sub-Antarctic islands to the coasts and continental shelf of Argentina. Considering the few specimens of S. bernasconiae ever collected as compared with the numerous samples available for other Sterechinus species (Larrain 1975 ), the taxonomic status and distribution range of the species were not revised in studies devoted to the systematics and biogeography of Austral echinoids (David et al. 2005 ; Dı´az et al. 2011 ; Gonza´lez-Wevar et al. 2012a ; Pierrat et al. 2012b , 2013 ). In light of the taxonomic issues raised in a recent study (Dı´az et al. 2011 ), the taxonomic status of S. bernasconiae and its phylogenetic relationships with S. agassizi and other species of Sterechinus had to be clarified.
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Seasonal distribution, movements and taxonomic status of blue whales (Balaenoptera musculus) in the northern Indian Ocean

Seasonal distribution, movements and taxonomic status of blue whales (Balaenoptera musculus) in the northern Indian Ocean

There is a distinct population of blue whales, Balaenoptera musculus, in the northern Indian Ocean. The taxonomic status of these animals has long been uncertain, with debate over whether this population represents a distinct subspecies, and if so which name should apply. They have most frequently been assigned to B. musculus brevicauda, but are currently considered to be B. m. indica. The movements of these blue whales within the northern Indian Ocean are poorly understood. This paper reviews catches (n = 1,288), sightings (n = 448, with a minimum of 783 animals), strandings (n = 64) and acoustic detections (n = 6 locations); uses ocean colour data to estimate seasonality of primary productivity in different areas of the northern Indian Ocean; and develops a migration hypothesis. It is suggested that most of these whales feed in the Arabian Sea off the coasts of Somalia and the Arabian peninsula during the period of intense upwelling associated with the southwest monsoon (from about May to October). At the same time some blue whales also feed in the area of upwelling off the southwest coast of India and west coast of Sri Lanka. When the southwest monsoon dies down in about October–November these upwellings cease. The blue whales then disperse more widely to eke out the leaner months of the northeast monsoon (during about December to March) in other localised areas with seasonally high productivity. These include the east coast of Sri Lanka, the waters west of the Maldives, the vicinity of the Indus Canyon (at least historically), and some parts of the southern Indian Ocean. The data are consistent with the hypothesis that at least some of the blue whales that feed off the east coast of Sri Lanka in the northeast monsoon also feed in the Arabian Sea during the southwest monsoon. These whales appear to migrate eastwards past the north of Maldives and south of Sri Lanka in about December–January, returning westwards in about April–May.
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Taxonomic status and phylogenetic relationship of some Algerian shallow-water sea cucumber species (Holothuroidea: Echinodermata) deduced from mitochondrial DNA sequences

Taxonomic status and phylogenetic relationship of some Algerian shallow-water sea cucumber species (Holothuroidea: Echinodermata) deduced from mitochondrial DNA sequences

CONCLUSION The present study allowed to revaluate the taxonomic status of some aspidochirotid holothurians species of the Algerian coast. The obtained results indicate that Holothuria (H.) tubulosa, the most common species in the Mediterranean Sea, has two distinct species that have been noted in the present work as morphotype A & morphotype B. The morphotype "A" corresponds to the classical Holothuria (Holothuria) tubulosa previously described by [13] ; while the morphotype "B" should corresponds to a new species whose molecular characteristics are different from those of Holothuria (H.) tubulosa A. We also reported a close relation- ship between Holothuria (H.) tubulosa A and Holothuria (R.) arguinensis which corroborates with other studies carried out on the genus Holothuria in the Mediterranean Sea and the Atlantic Ocean. The genetic tests showed very high haplotypic and nucleotide diversities.
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The alien's identity: consequences of taxonomic status for the international bumblebee trade regulations

The alien's identity: consequences of taxonomic status for the international bumblebee trade regulations

integrative approach based on differentiation in multiple genetic markers and CLGS composition suggested that 83.. terrestris included two species (B.[r]

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A reevaluation of the taxonomic status of the rodent Masillamys Tobien, 1954 from Messel (Germany, late early to early middle Eocene, 48–47 m.y.)

A reevaluation of the taxonomic status of the rodent Masillamys Tobien, 1954 from Messel (Germany, late early to early middle Eocene, 48–47 m.y.)

Its distal extremity bears a short ridge linked to a strong postmesoconid swelling or ridge, which is separated (MGL 222, 227, 233 and 665) or faintly connected to the lingua[r]

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About the taxonomic status of aspidochirotid holothurians inhabiting  the Posidonia oceanicameadow in the Algerian area

About the taxonomic status of aspidochirotid holothurians inhabiting the Posidonia oceanicameadow in the Algerian area

The Aspidochirotidae comprise a diverse assemblage of holothuroids, most of which occur in the Mediterranean Sea. The systematic study was carried out by using modern molecular systematic methods. Phylogenetic analyses from the fraction of mitochondrial gene (16S mDNA) sequenced for 169 individuals (6 species sampled in various localities of the Algerian shallow water areas) clarified taxonomic uncertainties, species relationships.

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Systematics of hairy armadillos and the taxonomic status of the Andean hairy armadillo (Chaetophractus nationi)

Systematics of hairy armadillos and the taxonomic status of the Andean hairy armadillo (Chaetophractus nationi)

variate analysis, Andean hairy armadillos are similar in size to specimens of C. vellerosus,[r]

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Isolation drives taxonomic and functional nestedness in tropical reef fish faunas

Isolation drives taxonomic and functional nestedness in tropical reef fish faunas

Fish taxonomic groups The taxonomic units considered in our analysis were reef fish families. The use of this taxonomic level is appropriate because it enables comparisons among reef fish assemblages across large biogeographic regions, since families tend to be more conservative (i.e. similar) across such regions when compared to reef fish genera for instance (Bellwood and Wainwright 2002, Floeter et al. 2008). The reef fish families considered herein comprise those referred to by Bellwood and Wainwright (2002) and Floeter et al. (2008), includ- ing the typical reef fish families Acanthuridae, Apogonidae, Blennidae, Carangidae, Chaetodontidae, Holocentridae, Labridae, Mullidae, Pomacentridae and Scaridae (Bellwood 1996), as well as other typical reef taxa that occur in cer- tain areas (Chaenopsidae, Labrisomidae, Siganidae, etc.). We counted the number of species in a given family occur- ring across all sites of provinces and biogeographic regions as defined by Kulbicki et al. (2013). The data were organized in quantitative matrices where rows denoted families and col- umns represented sites. Therefore each cell was filled with the number of species in a given family (rows) for a given site (columns). In our analysis, described below, we computed the family-level taxonomic nestedness, which we refer to simply as taxonomic nestedness throughout the manuscript. Site attributes
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Bioinformatic Genome Comparisons for Taxonomic and Phylogenic Assignments using Aeromonas as Test Case

Bioinformatic Genome Comparisons for Taxonomic and Phylogenic Assignments using Aeromonas as Test Case

monas species with the phylogeny generated from the expanded core and the HK genes. There were eight major clades from the EC that were largely consistent with the HK phylogeny (Fig. 1). One major difference between the two phylogenies was the placement of A. salmonicida (clade 7) and A. hydrophila and A. dhakensis (clade 2). In the EC phylogeny, they form one strongly supported clade, but in the HK phylogeny they are separated by two well- supported nodes (Fig. 1). This suggests that other components of the genome are forcing A. hydrophila and A. salmonicida together in the expanded core phylogeny. Due to the limited resolution, the RP phylogeny did not provide additional support. A strict core phylogeny using only ortholog groups present in all 56 taxa shared the topology of the EC tree, suggesting that the conflict with the HK method was due to genes present in 100% of the genomes (see Fig. S2 in the supplemental material). One should consider, how- ever, that the EC phylogeny may have inherent biases which might lead to an inaccurate depiction of organismal phylogeny. At this point, we cannot establish which topology is correct, since gene transfer between divergent groups has the potential to lead to trees from concatenated data sets that do not reflect the vertical inher- itance (19). Gene transfer frequency is usually biased toward close relatives, thus reinforcing the signal due to shared ancestry (53, 54). In contrast, highways of gene sharing between more distant species can obscure the vertical phylogenetic signal due to shared ancestry (51, 55). For phylogenetic relationships within each of the clades 1 through 7, the HK and EC phylogenies appear to approximate organismal phylogeny (Fig. 1). On the other hand, relationships between these clades remain ambiguous. Differences in substitution rates and saturation with substitutions make it difficult to apply ANI and isDDH to higher taxonomic levels. Fu- ture work will need to include the evaluation of the 2,710 individ- ual trees from the EC analysis in a combined analysis, such as the one described by Bansal, Alm, and Kellis (56), to determine the major conflicting phylogenetic signals retained in these genomes. Even so, both the HK and EC phylogenies provided more infor- mation regarding the relationships of different Aeromonas species than previous MLSA studies.
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Diverging taxonomic and functional trajectories following disturbance in a Neotropical forest

Diverging taxonomic and functional trajectories following disturbance in a Neotropical forest

267 𝜌 𝑆𝑝𝑒𝑎𝑟𝑚𝑎𝑛 𝐹𝑢𝑛𝑐𝑡𝑖𝑜𝑛𝑎𝑙 = 0.90, respectively). The maximum dissimilarity with the initial state was 268 reached for taxonomic composition between 15 to 25 years, and between 20 to 25 years for 269

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Taxonomic and functional diversity increase the aesthetic value of coralligenous reefs

Taxonomic and functional diversity increase the aesthetic value of coralligenous reefs

Fabrice Hoff 3 , Pierre Boissery 4 , Florian Holon 5 & Julie Deter 1,5 The aesthetic value of landscapes contributes to human well-being. However, studies which have investigated the link between biodiversity and ecosystem services have not taken aesthetic value into account. In this study we evaluated how the aesthetics of coralligenous reefs, a key marine ecosystem in the Mediterranean, is perceived by the general public and how aesthetic preferences are related to biodiversity facets (taxonomic, phylogenetic and functional diversities). We performed both biodiversity measures and online-surveys of aesthetic perception on photographic quadrats sampled along the French Mediterranean coast. Our results show that species richness and functional richness have a significant positive effect on aesthetic value. Most of the ecological literature, exploring the relationship between biodiversity and ecosystem functioning and service has focused so far on ‘economical’ aspects of biodiversity (provision or regulation). Our results illustrate that cultural facets, such as ‘beauty’, should also be central in our motivations to preserve ecological diversity.
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Delineating ecologically significant taxonomic units from global patterns of marine picocyanobacteria

Delineating ecologically significant taxonomic units from global patterns of marine picocyanobacteria

Figure S5a: Marine picocyanobacteria community structure in Tara Oceans surface metagenomes 36. based on petB- mi Tags recruitments[r]

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Rotifers in the Schelde estuary (Belgium): a test of taxonomic relevance

Rotifers in the Schelde estuary (Belgium): a test of taxonomic relevance

and E H 0 . In our data set, 9 out of 27 genera were plurispecific, and 18 monospecific. However, the plurispecific genera con- tained 64% of the species observed. The monospecific genera include 10 cases in which the species could not be identified, so we cannot be certain that they were indeed monospecific. The co-variation of diversity measured at species and genus level in our data set is partly due to the fact that calculating diversity at the species and genus level produced the same result for 36% of the species. It is difficult to say whether this type of rotifer population composition is common in estuaries. The taxonomic resolution used by Holst et al. ( Holst et al., 1998 ) in the study on the Elbe rotifers is different from ours for some genera. These authors used non-fixed samples, which enabled them to identify more non-loricate species.
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Status of the ARGOS project

Status of the ARGOS project

Leibniz-Institut für Astrophysik Potsdam ABSTRACT ARGOS is the Laser Guide Star and Wavefront sensing facility for the Large Binocular Telescope. With first laser light on sky in 2013, the system is currently undergoing commissioning at the telescope. We present the overall status and design, as well as first results on sky. Aiming for a wide field ground layer correction, ARGOS is designed as a multi- Rayleigh beacon adaptive optics system. A total of six powerful pulsed lasers are creating the laser guide stars in constellations above each of the LBTs primary mirrors. With a range gated detection in the wavefront sensors, and the adaptive correction by the deformable secondary’s, we expect ARGOS to enhance the image quality over a large range of seeing conditions. With the two wide field imaging and spectroscopic instruments LUCI1 and LUCI2 as receivers, a wide range of scientific programs will benefit from ARGOS. With an increased resolution, higher encircled energy, both imaging and MOS spectroscopy will be boosted in signal to noise by a large amount. Apart from the wide field correction ARGOS delivers in its ground layer mode, we already foresee the implementation of a hybrid Sodium with Rayleigh beacon combination for a diffraction limited AO performance.
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Status and Coordination in Organizations

Status and Coordination in Organizations

game. In this new stage, two workers with identical status compete for promotion, and the one who produces higher profit (or equivalently lower cost) wins the leading position and is awarded a higher status in the next stage. Such an award gives him entitlement to certain privileges, which lowers the leader’s cost in the next period. Worker 1 will

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Status of the AlCap experiment

Status of the AlCap experiment

As a cooperation between the two experiments, AlCap was created to measure low energy particle emission spectra after nuclear muon capture in target materials aluminium and titanium.. Th[r]

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Status report on the GANIL facility

Status report on the GANIL facility

L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignemen[r]

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Current Status of IPv6 Management

Current Status of IPv6 Management

Unité de recherche INRIA Lorraine LORIA, Technopôle de Nancy-Brabois - Campus scientifique 615, rue du Jardin Botanique - BP 101 - 54602 Villers-lès-Nancy Cedex France Unité de recherche[r]

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LISA Pathfinder: mission and status

LISA Pathfinder: mission and status

interferometer which measures the position and angles of test mass 1 with respect to the optical bench (and therefore, the spacecraft) - equivalent to the LISA local test mass interferom[r]

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The Current Status of CLASS

The Current Status of CLASS

I give a brief overview of the current status of some aspects of the Cosmic Lens All-Sky Survey, CLASS. 1 Who and What? CLASS, the Cosmic Lens All-Sky Survey, is a collaboration between groups at the Jodrell Bank Observatory (UK), ASTRON (NL), the Kapteyn Astronomical Institute at the University of Groningen (NL), Caltech (USA), the University of Pennsylvania (USA) and NRAO (USA). It is a survey for at-spectrum radio sources (  0 : 5 for S

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