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Journal of Applied Phycology - The red algal genus Vertebrata (Ceramiales, Rhodophyta) comprises 30 species of rather small filamentous algae, differing in morphology, distribution, and ecological...  相似文献   

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The mitochondrial genetic diversity, distribution and invasive potential of multiple cryptic operational taxonomic units (OTUs) of the red invasive seaweed Asparagopsis were assessed by studying introduced Mediterranean and Hawaiian populations. Invasive behavior of each Asparagopsis OTU was inferred from phylogeographic reconstructions, past historical demographic dynamics, recent range expansion assessments and future distributional predictions obtained from demographic models. Genealogical networks resolved Asparagopsis gametophytes and tetrasporophytes into four A. taxiformis and one A. armata cryptic OTUs. Falkenbergia isolates of A. taxiformis L3 were recovered for the first time in the western Mediterranean Sea and represent a new introduction for this area. Neutrality statistics supported past range expansion for A. taxiformis L1 and L2 in Hawaii. On the other hand, extreme geographic expansion and an increase in effective population size were found only for A. taxiformis L2 in the western Mediterranean Sea. Distribution models predicted shifts of the climatically suitable areas and population expansion for A. armata L1 and A. taxiformis L1 and L2. Our integrated study confirms a high invasive risk for A. taxiformis L1 and L2 in temperate and tropical areas. Despite the differences in predictions among modelling approaches, a number of regions were identified as zones with high invasion risk for A. taxiformis L2. Since range shifts are likely climate‐driven phenomena, future invasive behavior cannot be excluded for the rest of the lineages.  相似文献   

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A review of the genus Chironomus (Diptera,Chironomidae)   总被引:4,自引:0,他引:4  
Jon Martin 《Chromosoma》1974,45(1):91-98
Analysis of the banding pattern of the salivary gland chromosomes of Chironomus tepperi indicates that, despite a somewhat modified male hypopygium, the relationships of this species are close to the other Australian species of the genus, particularly to Ch. oppositus. No inversion polymorphism has been found in Ch. tepperi and this, together with the relatively high chiasma frequency as measured at metaphase I, would appear to be an adaptation to provide genetic variability necessary for its colonizing ability.  相似文献   

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The original collection of Aspidophora gaudichaudii Montagne was located in the Herbarium of the Laboratoire de Cryptogamie, Muséum National d'Histoire Naturelle (PC), and examined. An earlier report that the peltate, shield-like structures scattered over the lower surface of the blade surface were merely multicellular peglike rhizoidal attachments and not cystocarps was confirmed. The even earlier described Aglaophyllum peltatum Montagne has been found to be the same as Aspidophora gaudichaudii. Morphological evidence points to the identity of both Aspidophora gaudichaudii and Aglaophyllum peltatum with Cryptopleura corallinarum (Nott) Gardner. Because the name Aglaophyllum peltatum has priority, the binomial Cryptopleura peltata (Montagne) M. J. Wynne comb. nov. is proposed.  相似文献   

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类诺卡氏属放线菌的研究进展   总被引:1,自引:0,他引:1  
Prauser H.最初于1976年从土壤中分离到17株诺卡氏形态放线菌,综合形态、生理生化特性和部分化学分类特征的研究结果,提议建立了一个新属——类诺卡氏属(Nocardioides),并以新种白色类诺卡氏菌(N.albus)为典型种。之后,随着分离、纯培养和分类方法的发展,越来越多的新成员从各种不同环境中分离得到。尽管这些菌来源广泛,形态和生理生化等特征各异,但他们拥有共同的属的特征。过去的50年中,随着放线菌研究的发展,该属中部分成员历经了分类地位的变迁和修订。到目前为止,该属共收纳了56个有效描述种。类诺卡氏属(Nocardioides)放线菌在农业、工业、化工业等方面也曾有应用研究报道。本文就类诺卡氏属放线菌的建立依据,属的特征,属内种的分布和变更以及它们在工农业上的应用研究前景及进展进行了综述。  相似文献   

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The rhodophyte seaweed Asparagopsis armata Harvey is distributed in the northern and southern temperate zones, and its congener Asparagopsis taxiformis (Delile) Trevisan abounds throughout the tropics and subtropics. Here, we determine intraspecific phylogeographic patterns to compare potential causes of the disjunctions in the distributions of both species. We obtained specimens throughout their ranges and inferred phylogenies from the hypervariable domains D1-D3 of the nuclear rDNA LSU, the plastid spacer between the large and small subunits of RuBisCo and the mitochondrial cox 2-3 intergenic spacer. The cox spacer acquired base changes the fastest and the RuBisCo spacer the slowest. Median-joining networks inferred from the sequences revealed the absence of phylogeographic structure in the introduced range of A. armata, corroborating the species' reported recent introduction. A. taxiformis consisted of three nuclear, three plastid and four mitochondrial genetically distinct, lineages (1-4). Mitochondrial lineage 3 is found in the western Atlantic, the Canary Islands and the eastern Mediterranean. Mitochondrial lineages 1, 2, and 4 occur in the Indo-Pacific, but one of them (lineage 2) is also found in the central Mediterranean and southern Portugal. Phylogeographic results suggest separation of Atlantic and Indo-Pacific lineages resulted from the emergence of the Isthmus of Panama, as well as from dispersal events postdating the closure event, such as the invasion of the Mediterranean Sea by mitochondrial lineages 2 and 3. Molecular clock estimates using the Panama closure event as a calibration for the split of lineages 3 and 4 suggest that A. taxiformis diverged into two main cryptic species (1 + 2 and 3 + 4) about 3.2-5.5 million years ago (Ma), and that the separation of the mitochondrial lineages 1 and 2 occurred 1-2.3 Ma.  相似文献   

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Since the 1800s, natural health products that contain hawthorn (Crataegus spp.) have been used in North America for the treatment of heart problems such as hypertension, angina, arrhythmia, and congestive heart failure. Traditionally, Native American tribes used hawthorn (Crataegus spp.) to treat gastrointestinal ailments and heart problems, and consumed the fruit as food. Hawthorn also has a long history of use in Europe and China for food, and in traditional medicine. Investigations of Crataegus spp. typically focus on the identification and quantification of flavonoids and anthocyanins, which have been shown to have pharmacological activity. The main flavonoids found in Crataegus spp. are hyperoside, vitexin, and additional glycosylated derivatives of these compounds. Reviewed herein are the botany, ethnobotany, and traditional use of hawthorn while focusing on the phytochemicals that have been reported in Crataegus species, and the variation in the described chemistry between individual species.  相似文献   

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Between 1960 and 2009, regular visits to Svalbard were made and a number of Hebeloma spp. were collected by several mycologists. We have studied 249 such collections, many from the Herbarium in Oslo (O) and from the private herbarium of the first author. The collections represent 17 different species. Of the 17 species, five (H. louiseae, H. pallidolabiatum, H. perexiguum, H. pubescens and H. spetsbergense) are only known from Svalbard. In this paper we discuss the habitat and apparent associates of the 17 species recorded, as well as their frequency of occurrence within our sample, and compare this with our data from other regions of the northern hemisphere. A further analysis compares the records we have from the collection of basidiomes with data published from root analysis of mycorrhizal associates on Svalbard. Root associate data strongly suggest the occurrence of an unknown Hebeloma species, not close to any of the infrageneric groups known to occur in arctic habitats.  相似文献   

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The monotypic genus Evanos (Coleoptera: Rutelidae: Geniatini) is revised and a new species, E. danieleae Grossi, n. sp., is described based on specimens collected from Minas Gerais, Brazil. A lectotype is designated for Evanos villatus. Diagnostic characters and comments about the taxonomic status of the genus are given, as well as a key for both species and a distribution map with the known locality records.  相似文献   

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Thirteen species of petrified wood have been assigned previously to the genus Paraphyllanthoxylon which was established by Bailey (1924) as representative of the section Phyllanthoideae of the family Euphorbiaceae. Mädel (1962) considered the genus Paraphyllanthoxylon representative of only the Glochidion wood group of the section Phyllanthoideae. This necessitates the establishment of a new genus, Phyllanthoideoxylon, for fossil woods which have characteristics in common with several of the other wood groups in the section Phyllanthoideae. The thirteen previously identified species of Paraphyllanthoxylon are reviewed and compared with the characteristics of the genus. Eleven of these species are retained in Paraphyllanthoxylon Bailey (emend. Mädel), one (P. bangalamodense) is assigned to Phyllanthoideoxylon nov. gen. and one (P. keriense) is transferred to Bridelioxylon Ramanujam.  相似文献   

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Marusik YM  Koponen S 《ZooKeys》2010,(59):15-37
Eight species attributed to Tmeticus are reviewed; five are redescribed and illustrated: Tmeticus affinis (Blackwall, 1885), Tmeticus bipunctis (Bösenberg & Strand, 1906), Tmeticus nigriceps Kulczyński, 1916, Tmeticus ornatus (Emerton, 1914) and Tmeticus tolli Kulczyński, 1908. The new genus, Paratmeticus gen. n. is erected for Tmeticus bipunctis, and a new combination is established: Paratmeticus bipunctis (Bösenberg & Strand, 1906), comb. n. Three species names: Gongylidium vile Kulczyński, 1885, syn. n., Tmeticus difficilis Kulczyński, 1926, syn. n. and Tmeticus dubius Kulczyński, 1926, syn. n., are synonymized with Tmeticus tolli Kulczyński, 1908. Although Gongylidium vile has date priority over Tmeticus tolli it is synonymized because of the lack of usage. Three species from Japan attributed to Tmeticus: Tmeticus neserigonoides Saito & Ono, 2001, Tmeticus nigerrimus Saito & Ono, 2001 and Tmeticus vulcanicus Saito & Ono, 2001 are not related to Tmeticus affinis, the type species of the genus, and their affinities remain unclear. The male of Tmeticus nigriceps is described for the first time.  相似文献   

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A new occurrence of the onychochilid mollusc Pelecyogyra is reported from the late Floian Landeyran Formation (Apatokephalus incisus Biozone) in the Montagne Noire, southern France, where it is associated with the two tergomyans Carcassonnella courtessolei and Thoralispira laevis, and a mollusc indet. With a low cap-shaped shell. The Montagne Noire specimens compare morphologically with Pelecyogyra fezouataensis from the late Tremadocian Fezouata Formation (Araneograptus murrayi Biozone) in Morocco and are tentatively referred to this species. Each occurrence of Pelecyogyra is from one or two localities only, but separated in time. They differ further in the deeper facies, association with Carcassonnella and Thoralispira, and non-gregarious occurrence in Montagne Noire compared to the shallower facies, lack of other molluscs and gregarious occurrence in the Fezouata Formation. In the Lower Ordovician, Pelecyogyra, Carcassonnella courtessolei, the rare C. vizcainoi and Thoralispira laevis are taxa that occur only in Montage Noire and the Anti-Atlas, while Lesueurilla prima also occurs in the Prague basin of the Czech Republic. Contrary to other faunal elements, like echinoderms and trilobites, these genera seem to have a wide environmental tolerance and are long ranging taxa. The main occurrence of the three key taxa Carcassonnella, Thoralispira and Lesueurilla in the Montagne Noire is in the lower part of the La Maurerie Formation (Taihungshania miqueli acme Zone), while the same taxa appear just slightly later in Morocco (?Cymatograptus protobalticus Biozone). Migration to the Anti-Atlas during the early Floian seems to have been possible during a period of general faunal exchange. Pelecyogyra may either have migrated from the Anti-Atlas to Montagne Noire during the same interval or possibly during the late Floian as indicated by shared faunal elements between these two regions at that time.  相似文献   

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Currently, there are 6 recognized species in the genus Rhopalias. These parasites are found in the small intestines of numerous species of marsupials throughout North and South America. Small mistakes in various classical taxonomic works have given rise to recent and numerous misidentifications of these species. In this work, we examine a total of 99 specimens across all species from museum collections in an attempt to determine informative taxonomic characters to distinguish these species. Despite confusion in the literature, accurate identification of these species can be achieved by observing the presence or absence of oral and flanking spines anterior to the oral sucker.  相似文献   

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