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1.
2.
The occurrence of two alien alpheid shrimps of the genus Athanas Leach, 1814 [in Leach 1813–1814], the Indo-West Pacific A. dimorphus Ortmann, 1894 and the Eastern Atlantic A. nitescens (Leach, 1813 [in Leach 1813–1814]), on the coast of the state of S?o Paulo, Brazil, is reported. The presence of A. dimorphus extends the range of this species in the western Atlantic farther to the south in Brazil, whereas A. nitescens is reported for the first time in the western Atlantic, representing the second alien alpheid species on this side of the Atlantic and the twenty-first decapod crustacean introduced in Brazil. We provide morphological accounts of the material examined and illustrate the most important diagnostic characters of both species. An overview of the possible mechanisms of their introduction on the coast of S?o Paulo is also provided.  相似文献   

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4.
An assemblage of gastropods from the Thanetian of the Kolosh Formation from the Zakho region in northern Iraq is documented for the first time. The ten species represent the families Campanilidae Douvillé 1904, Potamididae H. & A. Adams 1854, Batillariidae Thiele 1929, Thiaridae Gill 1871, Pachychilidae Fischer & Crosse 1892, Cerithiidae Fleming 1822 and Pseudolividae de Gregorio 1880, suggesting a littoral to shallow sublittoral depositional environment. Six of the species are new and five are formally described as new species. At least seven species are also known from the Thanetian and/or Early Ypresian of the Ankara region in Turkey. Only a single species occurs also in the Paleocene of the Paris Basin. No relation to Paleocene and Eocene faunas of Pakistan and India is detectable. This points to a considerably bioprovincialism along the northern coast of the Tethys. Consequently we suppose the existence of an Anatolian Province in the Thanetian/Ypresian Mediterranean Region of the Tethys Realm, represented by rather homogeneous mollusc faunas from western Turkey and northern Iraq. Campanile zakhoense nov. sp., Pyrazopsis hexagonpyramidalis nov. sp., Pachymelania islamogluae nov. sp., “Faunus” dominicii nov. sp. and Pseudoaluco mesopotamicus nov. sp. are introduced as new species. Varicipotamides Pacaud & Harzhauser nov. nom. is proposed as the replacement name for Exechestoma Cossmann (1889) non Brandt (1837).  相似文献   

5.
The types of the species of the Coniacian ammonite genus Hemitissotia Peron, 1897, identified in the Iberian Peninsula (Spain and Portugal), which are currently held in the Wiedmann (Universität Tübingen, Germany) and Choffat (Instituto Geológico e Mineiro, Portugal) collections, have been revised and refigured. New specimens of the taxa Hemitissotia ceadouroensis Choffat, 1898, Hemitissotia celtiberica Wiedmann, 1975b, Hemitissotia turzoi Karrenberg, 1935, Hemitissotia dullai (Karrenberg 1935) and Hemitissotia lenticeratiformis Wiedmann in Wiedmann and Kauffman, 1978 have also been presented. As results, H. celtiberica has been considered as a junior synonym of H. ceadouroensis, and the lectotype of this species and the neotypes of H. turzoi and H. dullai have been designated and figured. Additionally, the geographical and stratigraphical distributions of all of these species have been determined with precision, and several phylogenetic relationships between them have been identified, revealing morphologies that become progressively smaller and more depressed and ornamented (hydrodynamically less efficient), interpreted as an adaptative response to sea-level changes.  相似文献   

6.
Two species of the genus Camponotites (Formicidae, Formicinae) are described from the Late Pliocene deposits of Willershausen, Lower Saxony, northern Germany: C. silvestris Steinbach, 1967, and C. steinbachi n. sp. The generic name Camponotites has been established for fossil (Tertiary) ants independently by Steinbach (Bericht der Naturhistorischen Gesellschaft zu Hannover 111:95–102, 1967) and by Dlussky (Trudy paleontologi?eskogo instituta, akademiâ nauk SSSR, 1981), each for materials of different stratigraphical and geographical origin. Though poorly described, Camponotites Steinbach, 1967, and the single included (type) species C. silvestris Steinbach, 1967 (a monotypic species from the Late Pliocene of Willershausen), were based upon indication in the sense of the ICZN. Therefore, both the generic and specific names are valid and available. Camponotites Dlussky, 1981 (and its type species C. macropterus Dlussky, 1981) were certainly introduced correctly and are therefore available, too; but due to its homonymy the generic name is not valid. The revision shows that in this rare case both generic names are not only homonyms but also synonyms.  相似文献   

7.
Joseph G. Meert 《Evolution》2012,5(4):547-554
During the voyage of the H.M.S. Beagle, Charles Darwin quickly realized that geographic isolation led to significant changes in the adaptation of local flora and fauna (Darwin 1859). Genetic isolation is one of the well-known mechanisms by which adaptation (allopatric speciation) can occur (Palumbi, Annu Rev Ecol Syst 25:547?C72, 1994; Ricklefs, J Avian Biol 33:207?C11, 2002; Burns et al., Evolution 56:1240?C52, 2002; Hendry et al., Science 290:516?C8, 2009). Evolutionary changes can also occur when landmasses converge or are ??bridged.?? An important and relatively recent (Pliocene Epoch) example known as the ??Great American Biotic Interchange?? allowed for the migration of previously isolated species into new ecological niches between North and South America (Webb 1985, Ann Mo Bot Gard 93:245?C57, 2006; Kirby and MacFadden, Palaeogeogr Palaeoclimatol Palaeoecol 228:193?C202, 2005). Geographic isolation (vicariance) or geographic merging (geodispersal) can occur for a variety of reasons (sea level rise, splitting of continents, mountain building). In addition, the growth of a large supercontinent (or breakup) may change the climatic zonation on the globe and form a different type of barrier for species migration. This short review paper focuses on changing paleogeography throughout the Phanerozoic and the close ties between paleogeography and the evolutionary history of life on Earth.  相似文献   

8.
Icriocarcininae ?tev?i?, 2005, an extinct North American subfamily of portunoid decapods, is elevated to family level to contain two Late Cretaceous genera—Icriocarcinus Bishop, 1988, from the Pacific Coast, and Branchiocarcinus Feldmann and Vega, 1995, from the Gulf of Mexico and Atlantic Coast Plain. The family is centered on Icriocarcinus xestos Bishop, 1988, described from the Late Campanian of Baja California. Closely allied with this species are: “Erymaflecta Rathbun, 1926, originally described from the latest Campanian of Tennessee and now known to occur throughout the Maastrichtian of the adjoining Mississippi; Branchiocarcinus cornatus Feldmann and Vega, 1995, from the Maastrichtian of San Luis Potosí, Mexico; and undescribed material from the latest Maastrichtian of New Jersey. The Gulf and Atlantic populations compose a single new species—Branchiocarcinus flectus (Rathbun). Provisionally regarded as a lobster, on the basis of a single, eroded chela, B. flectus is now known from complete bodies found at several locations in the eastern US. The additional material also clarifies the identity of B. cornatus, which is based on a distorted external mold of a lone dorsal carapace. Members of the family lack the typical portunoid flattened fifth pereiopod but share other characters that enable placement within the Portunoidea.  相似文献   

9.
Sensory neurons in vertebrates are derived from two embryonic transient cell sources: neural crest (NC) and ectodermal placodes. The placodes are thickenings of ectodermal tissue that are responsible for the formation of cranial ganglia as well as complex sensory organs that include the lens, inner ear, and olfactory epithelium. The NC cells have been indicated to arise at the edges of the neural plate/dorsal neural tube, from both the neural plate and the epidermis in response to reciprocal interactions Moury and Jacobson (Dev Biol 141:243?C253, 1990). NC cells migrate throughout the organism and give rise to a multitude of cell types that include melanocytes, cartilage and connective tissue of the head, components of the cranial nerves, the dorsal root ganglia, and Schwann cells. The embryonic definition of these two transient populations and their relative contribution to the formation of sensory organs has been investigated and debated for several decades (Basch and Bronner-Fraser, Adv Exp Med Biol 589:24?C31, 2006; Basch et al., Nature 441:218?C222, 2006) review (Baker and Bronner-Fraser, Dev Biol 232:1?C61, 2001). Historically, all placodes have been described as exclusively derived from non-neural ectodermal progenitors. Recent genetic fate-mapping studies suggested a NC contribution to the olfactory placodes (OP) as well as the otic (auditory) placodes in rodents (Murdoch and Roskams, J Neurosci Off J Soc Neurosci 28:4271?C4282, 2008; Murdoch et al., J Neurosci 30:9523?C9532, 2010; Forni et al., J Neurosci Off J Soc Neurosci 31:6915?C6927, 2011b; Freyer et al., Development 138:5403?C5414, 2011; Katoh et al., Mol Brain 4:34, 2011). This review analyzes and discusses some recent developmental studies on the OP, placodal derivatives, and olfactory system.  相似文献   

10.
The growth of many organisms is seasonal, with a dependence on variation in temperature, light, and food availability. A growth model proposed by Somers (Fishbyte 6:8?C11, 1988) is one of the most widely used models to describe seasonal growth. We point out that three different formulae (beyond numerous typographical errors) have been used in the literature referring to Somers (Fishbyte 6:8?C11, 1988). These formulae correspond to different curves and yield different parameter estimates with different biological interpretations. These inconsistencies have led to the wrong identification of the period of lowest growth rate (winter point) in some papers of the literature. We urge authors to carefully edit their formulae to assure use of the original definition in Somers (Fishbyte 6:8?C11, 1988).  相似文献   

11.
From amphipod collections from the deep Norwegian Sea, three species are here redescribed: Maera loveni (Bruzelius 1859) (Maeridae), Leucothoe aff. spinicarpa (Abildgaard, 1789) and L. uschakovi Gurjanova, 1951 (Leucothoidae). A key to all Atlantic and Mediterranean Leucothoe species (males only) is provided.  相似文献   

12.
The fishes of the genus Aspidorhynchus (Aspidorhynchidae) are among the most abundant predators in the palaeolagoons of the Solnhofen archipelago (Late Jurassic, southern Germany). They have been known since the end to the nineteenth century and the last revision of the genus was published more than 20 years ago. During these last two decades, numerous complete and excellently preserved specimens have been collected. The high morphological diversity shown by the new material made a new revision of these fishes necessary. This new taxonomic revision led us to revalidate the species A. ornatissimus Agassiz, 1834, which has hitherto been considered a junior synonym of the type species of the genus, A. acutirostris (Blainville, 1818), as well as to recognize high intraspecific variation in the latter species. These results helped to improve the distinction and, thus, the diagnoses of A. acutirostris, A. ornatissimus, and A. sanzenbacheri Brito and Ebert, 2009, which are the three valid species of this genus in the Solnhofen archipelago. We have been able to explain most of the intraspecific diversity of A. acutirostris by means of patterns of ontogenetic variation that encompass most of the other nominal species, thus largely reflecting early taxonomic hypotheses. Furthermore, the detailed morphological study led us to the recognition of some important anatomical structures previously unknown for aspidorhynchids: a connection between the temporal, infraorbital and supraorbital sensory canals in the frontal bone, the presence of an Y-shaped antorbital bone, and the presence of an interoperculum.  相似文献   

13.
Following a strategy similar to that used in baker’s yeast (Herrgård et al. Nat Biotechnol 26:1155–1160, 2008). A consensus yeast metabolic network obtained from a community approach to systems biology (Herrgård et al. 2008; Dobson et al. BMC Syst Biol 4:145, 2010). Further developments towards a genome-scale metabolic model of yeast (Dobson et al. 2010; Heavner et al. BMC Syst Biol 6:55, 2012). Yeast 5—an expanded reconstruction of the Saccharomyces cerevisiae metabolic network (Heavner et al. 2012) and in Salmonella typhimurium (Thiele et al. BMC Syst Biol 5:8, 2011). A community effort towards a knowledge-base and mathematical model of the human pathogen Salmonella typhimurium LT2 (Thiele et al. 2011), a recent paper (Thiele et al. Nat Biotechnol 31:419–425, 2013). A community-driven global reconstruction of human metabolism (Thiele et al. 2013) described a much improved ‘community consensus’ reconstruction of the human metabolic network, called Recon 2, and the authors (that include the present ones) have made it freely available via a database at http://humanmetabolism.org/ and in SBML format at Biomodels (http://identifiers.org/biomodels.db/MODEL1109130000). This short analysis summarises the main findings, and suggests some approaches that will be able to exploit the availability of this model to advantage.  相似文献   

14.
The ??traditional?? distinction of compounds into endocentric (Eng. doorknob) and exocentric (pickpocket) is based on the presence or absence of a head constituent (Bloomfield, Language, Holt, New York, 1933); since the early eighties, the syntactic notion of ??head?? has been extended also to derivation, claiming that English derivational suffixes, as e.g. -ness, are heads, either in an absolute sense or in a categorial sense (see Williams Linguist Inq 12:245?C274, 1981; Lieber On the organization of the lexicon, Indiana university Linguistics Club, Bloomington, 1981; Lieber, in Yearbook of morphology 1989, Foris, Dordrecht, 1989; among others). In this paper, we shall first review some key issues in the morphological notion of head, illustrating well-known problematic cases, and then we shall discuss the Construction Morphology approach to headedness in derivation and compounding (Booij in The Oxford handbook of compounding, Oxford University Press, Oxford, 2009; Booij, in Cross-disciplinary issues in compounding, John Benjamins, Amsterdam, 2010a, 2010 Booij, Construction morphology, Oxford University Press, Oxford, 2010b). The stipulation of a hierarchical lexicon with subschemas expressing intermediate generalizations is a powerful theoretical device in accounting for a phenomenon as headedness variation, as we shall show with a Vietnamese case study; also, inconsistencies in word-class assignment in derivation will be dealt with in a constructionist perspective. Moreover, we shall discuss the consequences of a constructionist approach to the distinction between compounding and derivation.  相似文献   

15.

Purpose

This article discusses the choice of stakeholder categories and the integration of stakeholders into participatory processes to define impact categories and select indicators.

Methods

We undertook a literature review concerning the roles and the importance of stakeholders in participatory processes, and the use of such processes in environmental and social LCAs (Biswas et al. Int J Life Cycle Assess 3(4):184-190, 1998; Sonnemann et al. Int J Life Cycle Assess 6(6):325-333, 2001; Baldo Int J Life Cycle Assess 7(5):269-275, 2002; James et al. Int J Life Cycle Assess 7(3):151-157, 2002; Bras-Kapwijk Int J Life Cycle Assess 8(5):266-272, 2003; Mettier et al. Int J Life Cycle Assess 11(6):468-476, 2006). As part of the French National Research Agency Piscenlit project, we adapted the Principle, Criteria, Indicator (PCI) method (Rey-Valette et al. 2008), which is an assessment method of sustainable development, as a way to integrate the participatory approach into Social Life Cycle Assessment (SLCA) methodology, mainly at the impact definition stage.

Results and discussion

Different views of participation were found in the literature; there is no consensual normative approach for the implication of stakeholders in LCA development. Some attempts have been made to integrate stakeholders into environmental LCAs but these attempts have not been generalized. However, they strongly emphasize the interrelationship between research on the growing integration of stakeholders and on the choice of stakeholders. We then propose criteria from stakeholder theory (Freeman 1984; Mitchell et al. Acad Manage Rev 22(4):853-886, 1997; Geibler et al. Bus Strat Environ 15:334-346, 2006) in order to identify relevant stakeholders for SLCA participatory approach. The adaptation of the PCI method to Principles, Impacts, and Indicators (PII) enables stakeholders to express themselves and hence leads to definitions of relevant social indicators that they can appropriate. The paper presents results regarding the selection of stakeholders but no specific results regarding the choice of impact categories and indicators.

Conclusions and recommendations

Integrating a participatory approach into SLCAs is of interest at several levels. It enables various factors to be taken into account: plurality of stakeholder interests, local knowledge, and impact categories that make sense for stakeholders in different contexts. It also promotes dialogue and simplifies the search for indicators. However, it requires a multidisciplinary approach and the integration of new knowledge and skills for the SLCA practitioners.  相似文献   

16.
A new demospongid genus and species is described from the Upper Jurassic (Lower Tithonian) Plattenkalk of Langenaltheim near Solnhofen/Bavaria. Both the morphology and the spiculation of the new taxon Neochoiaella frattigianii n. gen. n. sp., which lacks a rigid skeleton, resemble the Early Cambrian family Choiidae de Laubenfels, 1955, particularly the genus Choiaella Rigby and Hou, 1995 from the Cengjiang Fossillagerst?tten of Yunnan/Southern China. Due to the complete preservation of the specimen, we cannot exclude the possibility that Neochoiaella n. gen. was living at its place of burial in the Plattenkalk basin of Solnhofen, but it seems more likely that it was washed in as an allochthonous faunal element, like other benthic organisms from this limestone. Similarly, the hexactinellid reticulate sponge Ammonella quadrata Walther, 1904, which appears to be restricted to the small Plattenkalk basin of Pfalzpaint, led to speculation about a possible Lazarus taxon due to its spicular architecture, which corresponds to that seen in the Early Palaeozoic Protospongiidae Hinde, 1887. Possibly, the special environmental conditions that existed within or close to the Plattenkalk basins provided a niche in which anachronistic taxa such as Neochoiaella n. gen. and Ammonella Walther, 1904 could have survived.  相似文献   

17.
Ugis Kagainis 《Zoomorphology》2014,133(2):227-236
In the past, micro-arthropod taxonomists have mainly relied on qualitative characters to identify species, and relatively little attention has been paid to quantitative analysis. However, several taxonomic groups have high morphological variability, which creates problems in identification. Quantitative analysis of morphometrical data of specific characters could aid in understanding differences in the morphology of oribatid species. In this respect, confocal laser scanning microscopy and quantitative analysis were used to describe morphological traits of four oribatid mite species belonging to the genus Carabodes Koch, 1835C. femoralis (Nicolet, 1855), C. labyrinthicus (Michael, 1879), C. ornatus Storkan, 1925 and C. subarcticus Trägårdh, 1902. All specimens were collected in Latvia. Thirteen morphological traits were measured for 838 adult individuals. The same traits were also measured with transmitted light microscopy, and results were compared. The impact of a number of environmental factors on traits was also assessed. High interspecific variability in size of most morphological features was observed. In many cases, sizes of the measured features correlated between different species. The ranges in length of notogastral setae p3 and h3 of C. femoralis did not overlap with those of C. labyrinthicus or C. ornatus. Significant correlations between body length and size of setal structures, as well as between setal structures, were detected. Size of morphological features was directly affected by the cover of lichens, a main food resource for Carabodes, and indirectly by the effect of soil moisture on lichen communities.  相似文献   

18.
We investigate several versions of a simple game of sexual selection, to explore the role of secondary sexual characters (the “handicap paradox”) with the tools of signaling theory. Our models admit closed form solutions. They are very much inspired by Grafen’s (J Theor Biol 144:517–546, 1990a; J Theor Biol 144:473–516, 1990b) seminal companion papers. By merging and simplifying his two approaches, we identify a not so minor artifact in the seminal study. We propose an alternative model to start with Grafen’s sexual selection theory, with several similarities with Getty (Anim Behav 56:127–130, 1998).  相似文献   

19.
The taxonomy of the Atlantic and Eastern Pacific species of Kyphosus is reviewed with K. bosquii (Lacepède 1802), K. incisor (Cuvier 1831), K. analogus (Gill 1862) and K. elegans (Peters 1869) considered valid, and K. atlanticus sp. nov. newly described. Kyphosus bosquii and K. atlanticus are both characterized by 12 dorsal- and 11 anal-fin soft rays, but differ in the number of longitudinal scale rows along the midbody (61–66, mode 63 vs. 50–56, mode 54). Kyphosus incisor and K. analogus, characterized by 14 dorsal- and 13 anal-fin soft rays, similarly differ from each other in midbody longitudinal scale row counts (57–64, mode 60 vs. 68–74, mode 70 or 72). Kyphosus elegans is characterized by 13 dorsal- and 12 anal-fin soft rays, and 51–57 midbody longitudinal scale rows. Kyphosus bosquii, K. atlanticus and K. incisor are distributed in the Atlantic Ocean, K. analogus and K. elegans occurring in the Eastern Pacific. The holotype of Pimelepterus flavolineatus Poey 1866, here regarded as a junior synonym of K. incisor, was located within a collection of Cuban fishes donated to the Smithsonian Institution by Poey in 1873. A neotype is designated here for K. analogus. Pimelepterus gallveii Cunningham 1910, Kyphosus palpebrosus Miranda-Ribeiro 1919 and K. metzelaari Jordan and Evermann 1927 are recognized as junior synonyms of K. bosquii. Pimelepterus sandwicensis Sauvage 1880 is a junior synonym of K. elegans. Perca saltatrix Linnaeus 1758, together with the replacement name Perca sectatrix Linnaeus 1766, is regarded as nomina dubia.  相似文献   

20.
The dynamics inherent to the life activity of all living systems presents itself in the form of regular patterns viewed by the observer as taking place in an extended timeline. Routines, rituals and celebrations, each in their own way, are defined by the typical cyclical behavioural patterns exhibited by individuals embedded in specific semiospheres. The particular nature of these semiospheres will determine the distinct patterns of behaviour to be adopted in different life contexts so that existential functions are fulfilled. The restricted and protected family circle normally provides the initial learning environment where the definition of the individual’s Umwelt (von Uexküll 1909, 1934; Ferreira, Biosemiotics 3(1):107–130, 2010, 2011) his/her meaningful world, starts to take shape. This learning process comprehends the progressive identification of distinct physical entities, the development of basic patterns of physical and social behaviour- the incorporation of basic routines and the assignment of meaning to particular events.  相似文献   

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