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1.
Polypteridae is a family of archaic freshwater African fish that constitute an interesting subject for the study of the karyological evolution in vertebrates, on account of their primitive morphological characters and peculiar relationships with lower Osteichthyans. In this paper, a cytogenetic analysis on twenty specimens of both sexes of Polypterus ornatipinnis the ornate "bichir", coming from the Congo River basin, was performed by using both classical and molecular techniques. The karyotypic formula (2n=36; FN=72) was composed of 26 M+10 SM. The Alu I banding, performed to characterize heterochromatin in this species, was mainly centromeric. Both the chromosome location of the ribosomal 5S and 18S rRNA genes were examined by using Ag-NOR, classical C-banding, CMA(3) staining and FISH. CMA(3) marked all centromerical regions and showed the presence of two GC rich regions on the p arm of the chromosome pair n°1 and on the q arm of the pair n°14. Staining with Ag-NOR marked the only telomeric region of the chromosome n°1 p arm. After PCR, the 5S rDNA in this species was cloned, sequenced and analyzed. In the 665bp 5S rDNA sequence of P.ornatipinnis, a conserved 120bp gene region for the 5S rDNA was identified, followed by a non-transcribed variable spacer (NTS) which included simple repeats, microsatellites and a fragment of a non-LTR retrotransposon R-TEX. FISH with 5S rDNA marked the subtelomeric region of the q arm of the chromosome pair n°14, previously marked by CMA(3). FISH with 18S rDNA marked the telomeric region of the p arm of the pair n°1, previously marked both by Ag-NOR and CMA(3). The (GATA)(7) repeats marked the telomeric regions of all chromosome pairs, with the exclusion of the n°1, n°3 and n°14; hybridization with telomeric probes (TTAGGG)(n) showed signals at the end of all chromosomes. Karyotype evolution in Polypterus genus was finally discussed, including the new data obtained.  相似文献   

2.
This study identified 431 psychrophilic or psychrotrophic isolates from commercial Irish beef abattoir environments and "blown packs" of vacuum-packed beef, using PCR and 16S rRNA sequencing, and estimated their intraspecies genetic diversity using restriction fragment length polymorphism (RFLP) analysis and spacer region PCR (SR-PCR). Twenty-five species were identified in the 431 isolates, with the most frequently recovered species being Clostridium gasigenes (n=315), Clostridium estertheticum (n=17), and a potentially novel species designated strain TC1 (n=52). These species were previously found to be associated with a particular type of spoilage known as blown-pack spoilage (BPS), which occurs in chilled-stored (i.e., -1.5°C to 4°C) vacuum-packaged meat within 2 to 4 weeks and involves the production of large volumes of gas. Overall, the study demonstrates the considerable and not previously reported diversity of the anaerobic microflora in abattoirs and the presence of a wide range of organisms capable of causing BPS at chilled temperatures.  相似文献   

3.
Twelve species are considered within the Afrotropical genus Strigivenifera Hering, 1937, and ten of them are described as new ones: S. eborea sp. n.,S. livingstonei sp. n., S. marina sp. n., S. tanja sp. n., S. ocellaris sp. n., S. cruisa sp. n., S. bartschi sp. n., S. oris sp. n., S. tatooifera sp. n., and S. neo sp. n. The species S. albidiscalis (Hampson, 1910) is raised from synonymy with S. venata (Aurivillius, 1895) and considered as a separate species.  相似文献   

4.
Koen Martens 《Hydrobiologia》1988,162(3):243-273
Sclerocypris dayae n.sp., S. dedeckkeri n.sp., S. dumonti n.sp., S. zelaznyi n.sp. and S. zelaznyi etoshensis n.ssp. are described from South — West Africa (Namibia). S. exserta makarikarensis n.ssp. originates from the endorheic pan system Makarikari in Botswana. S. woutersi n.sp. was described from Lake Albert where it is quite common. S. virungensis n.sp. is known from the Virunga National Park, south of Lake Edward (Zaire). The latter two species are closely related and from part of the flabella-species group. S. longisetosa n.sp., described from a marsh near Kisumu (Kenya), is an enigmatic species, holding an isolated position in the genus due to an aberrant T1.Present address: Rijksuniversiteit Gent, Laboratorium voor ecologie der dieren, zoögeografte en natuurbehoud (Institute for Ecology), K. L. Ledeganckstraat 35, B9000 Gent, Belgium.  相似文献   

5.
The climatic variability hypothesis (CVH) states that species are geographically more widespread at higher latitudes because individuals have a broader range of physiological tolerance or phenotypic flexibility as latitude and climatic variability increase. However, it remains unclear to what extent climatic variability or latitude, acting on the phenotype, account for any observed geographical gradient in mean range size. In this study, we analyzed the physiological flexibility within the CVH framework by using an intraspecific population experimental approach. We tested for a positive relationship between digestive-tract flexibility (i.e., morphology and enzyme activities) and latitude and climatic and natural diet variability in populations of rufous-collared sparrows (Zonotrichia capensis) captured in desert (27°S), Mediterranean (33°S), and cold-temperate (41°S) sites in Chile. In accordance with the CVH, we observed a positive relationship between the magnitude of digestive-tract flexibility and environmental variability but not latitude. The greatest digestive flexibility was observed in birds at middle latitudes, which experience the most environmental variability (a Mediterranean climate), whereas individuals from the most stable climates (desert and cold-temperate) exhibited little or no digestive-tract flexibility in response to experimental diets. Our findings support the idea that latitudinal gradients in geographical ranges may be strongly affected by the action of regional features, which makes it difficult to find general patterns in the distribution of species.  相似文献   

6.
The genus Scelio is a cosmopolitan and speciose group of solitary parasitoids of the eggs of short-horned grasshoppers (Orthoptera: Acrididae). A number of these hosts are important pests, including plague locusts of the genus Schistocerca. Species of Scelio are recognized as potentially important biological control agents, but this possibility has yet to be fully realized, in part because the species-level taxonomy is still incompletely developed. The species of the pulchripennis group have been recently revised. As a continuation of this effort, here we revise the Afrotropical species of Scelio, excluding the pulchripennis species group. Sixty two (62) species are treated, 48 of which are new. Species are classified into the following species groups: ernstii (12 species, 9 new), howardi (23 species, 19 new), ipomeae (6 species, 5 new), irwini (4 species, 3 new), simoni (3 new species) and walkeri (12 species, 9 new). Keys to species groups and to the species within each group are provided. New species described are: S. albatus Yoder, sp. n., S. aphares Yoder, sp. n., S. apospastos Yoder, sp. n., S. ardelio Yoder, sp. n., S. aurantium Yoder, sp. n., S. balo Valerio & Yoder, sp. n., S. bayanga Yoder, sp. n., S. bubulo Yoder, sp. n., S. cano Yoder, sp. n., S. clypeatus Yoder, sp. n., S. concavus Yoder, sp. n., S. copelandi Yoder, sp. n., S. crepo Yoder, sp. n., S. destico Yoder, sp. n., S. dupondi Yoder, sp. n., S. effervesco Yoder, sp. n., S. erugatus Yoder, sp. n., S. exophthalmus Yoder, sp. n., S. fremo Valerio & Yoder, sp. n., S. gemo Yoder, sp. n., S. grunnio Yoder, sp. n., S. harinhalai Yoder, sp. n., S. igland Yoder, sp. n., S. impostor Yoder, sp. n., S. irwini Yoder, sp. n., S. janseni Yoder, sp. n., S. latro Yoder, sp. n., S. memorabilis Yoder, sp. n., S. modulus Yoder, sp. n., S. mutio Yoder, sp. n., S. ntchisii Yoder, sp. n., S. parkeri Yoder, sp. n., S. phaeoprora Yoder, sp. n., S. pilosilatus Yoder, sp. n., S. pipilo Yoder, sp. n., S. quasiclypeatus Yoder, sp. n., S. retifrons Yoder, sp. n., S. ructo Yoder, sp. n., S. scomma Yoder, sp. n., S. simoni Yoder, sp. n., S. simonolus Yoder, sp. n., S. somaliensis Yoder, sp. n., S. susurro Yoder, sp. n., S. tono Yoder, sp. n., S. transtrum Yoder, sp. n., S. tritus Yoder, sp. n., S. ululo Yoder, sp. n., S. vannoorti Valerio & Yoder, sp. n. The following species are redescribed: S. afer Kieffer, S. chapmani Nixon, S. howardi Crawford, S. ipomeae Risbec, stat. n., S. mauritanicus Risbec, S. philippinensis Ashmead, S. remaudierei Ferrière, S. striatus Priesner,S. taylori Nixon, and S. zolotarevskyi Ferrière. The genus Lepidoscelio Kieffer is treated as a junior synonym of Scelio Latreille, syn. n.; its type species, Lepidoscelio fuscipennis Kieffer, 1905 is transferred to Scelio, renamed Scelio obscuripennis Johnson, nom. n. (preoccupied by Scelio fuscipennis Ashmead, 1887), and redescribed. The following additional species are transferred from Lepidoscelio to Scelio: S. cayennensis (Risbec), comb. n., S. insularis Ashmead, rev. comb., S. luteus (Cameron), comb. n., S. thoracicus Ashmead, rev. comb. Lectotypes are designated for S. africanus Risbec, S. ipomeae Risbec, S. mauritanicus Risbec, S. remaudierei Ferrière, S. sudanensis Ferrière, and S. zolotarevskyi Ferrière. Scelio gaudens Nixon is a junior synonym of Scelio striatus Priesner, syn. n.; Scelio africanus Risbec and Scelio clarus Fouts are both junior synonyms of Scelio afer Kieffer, syn. n.; Scelio sudanensis Ferrière and Scelio cheops Nixon are both junior synonyms of Scelio zolotarevskyi Ferrière, syn. n.; Scelio cahirensis Priesner is a junior synonym of Scelio mauritanicus Risbec, syn. n. The name Scelio chapmanni Nixon is an incorrect original spelling, requiring an emendation to S. chapmani. Digital versions of the identification keys are available at http://www.waspweb.org/Platygastroidea/Keys/index.htm  相似文献   

7.
Fifty-nine species of Tubifieidae are recorded from Belize on the Caribbean side of Central America. Twenty-five are new to science: Ainudrilus geminus sp.n., Heronidrilus gravidus sp.n., Heterodrilus flexuosus sp.n., H. ranus sp.n., H. modestus sp.n., Coralliodrilus rugosus sp.n., C. randyi sp.n., Phallodrilus compactus sp. n., P. singularis sp.n., P. vicinus sp.n., P. nasutus sp.n., P. bipartitus sp.n., Inanidrilus reginae sp.n., Olavius finitimus sp.n., O. vacuus sp.n., O. (Olavius) pravus sp.n., Bathydrilus vetustus sp.n., B. egenus sp.n., Thalassodrilides bruneti sp.n., Limnodriloides anxius sp.n., L. major sp.n., L. sacculus sp.n., L. adversus sp.n., Smithsonidrilus appositus sp.n., S. involutus sp.n. Phylogenetic analyses indicate that Heterodrilus Pierantoni, 1902, Thalassodrilides Brinkhurst & Baker, 1979, and Marcusaedrilus Righi & Kanner, 1979, are paraphyletic taxa as previously defined. They are therefore revised to include also apomorphic species earlier attributed to separate genera; in so doing, Marcusaedrilus becomes a junior synonym of Smithsonidrilus Brinkhurst, 1966. Smithsonidrilus pauper sp.n. (Peru), and S. multiglandularis sp.n. (Florida and Puerto Rico) are also described, and Limnodriloides claviger Erséus, 1982 is regarded as a synonym of L. pierantonii (Hrabě, 1971).  相似文献   

8.
The effect of temperature on sperm motility was investigated in brown trout Salmo trutta, burbot Lota lota and grayling Thymallus thymallus using water and sperm motility prolonging saline solution (SMPS) for motility activation. The effect of temperature (4-20° C) on spermatozoal enzymes for energy supply [malate dehydrogenase (MDH), pyruvate kinase (PK), adenylate kinase (AK)], flagellar movement [Mg(2+) adenosine triposphatase (ATPase)] and oxidative defence [peroxidase (POX)] were measured in S. trutta and L. lota. Temperatures yielding the highest initial sperm motility rates and swimming velocities were 4-6° C for S. trutta [investigated range (IR) = 4-12° C] and L. lota (IR = 2-8° C) and 8-16° C (IR = 4-16° C) for T. thymallus. Motility variables were re-measured after 30 s in S. trutta, after 45 s in T. thymallus and after 60 s in L. lota in water and after 2 min in all investigated species in SMPS. Motility variables were increased by low temperatures and the results differed between water and SMPS. In S. trutta and L. lota, the temperature resulting in highest activities of MDH, PK, AK and ATPase was 4° C. POX had a very narrow temperature optimum at 20° C in both species. This may indicate that the temperature optimum of enzymes of energy supply and flagellar movement are closely related to motility. The present data show that the variables are affected by temperatures in an ecologically relevant range. Too low, as well as too high temperatures affected sperm motility, and the winter spawners (S. trutta and L. lota) have a narrower temperature optimum than the spring spawner T. thymallus.  相似文献   

9.
Three new species of the Oriental caliscelid planthopper genus Symplanella Fennah, S. hainanensis sp. n., S. recurvata sp. n. and S. zhongtua sp. n., are described and illustrated from South China. A checklist and a key to species of genus Symplanella are provided.  相似文献   

10.
2020年5月23日在湖南省通道县万佛山镇(26° 11′47″N,109°56′21″E,海拔924 m)采集到4号两栖动物标本,经形态特征比较,与雷山琴蛙(Nidirana leishanensis)相似;基于线粒体16S rRNA构建的琴蛙属(Nidirana)部分物种贝叶斯系统发育树显示,此次采集的琴蛙标本与雷...  相似文献   

11.
Hyperthermophilic micro-organisms grow at temperatures above 90 °C with a current upper limit of 113 °C. They are a recent discovery in the microbial world and have been isolated mainly from marine geothermal environments, which include both shallow and deep sea hydrothermal vents. By 16S rRNA analyses they are the most slowly evolving of all extant life forms, and all but two of the nearly 20 known genera are classified as Archaea (formerly Archaebacteria). Almost all hyperthermophiles are strict anaerobes. They include species of methanogens, iron-oxidizers and sulphate reducers, but the majority are obligate heterotrophs that depend upon the reduction of elemental sulphur (S°) to hydrogen sulphide for significant growth. The heterotrophs utilize proteinaceous materials as carbon and energy sources, although a few species are also saccharolytic. A scheme for electron flow during the oxidation of carbohydrates and peptides and the reduction of S° has been proposed. Two S°-reducing enzymes have been purified from the cytoplasm of one hyperthermophile (T(opt) 100 °C) that is able to grow either with and without S°. However, the mechanisms by which S° reduction is coupled to energy conservation in this organism and in obligate S°-reducing hyperthermophiles is not known. In the heterotrophs, sugar fermentation is achieved by a novel glycolytic pathway involving unusual ADP-dependent kinases and ATP synthetases, and novel oxidoreductases that are ferredoxin- rather than NAD(P)-linked. Similarly, peptide fermentation involves several unusual ferredoxin-linked oxidoreductases not found in mesophilic organisms. Several of these oxido-reductases contain tungsten, an element that is rarely used in biological systems. Tungsten is present in exceedingly low concentrations in normal sea water, but hydrothermal systems contain much higher tungsten concentrations, more than sufficient to support hyperthermophilic life.  相似文献   

12.
Ting-jing Li  Bin Chen 《ZooKeys》2014,(389):9-26
In this study, we recognize and review a total of 19 species of the genus Symmorphus Wesmael from China. We also provide a key to these species. Three new species are described and illustrated, namely Symmorphus (Symmorphus) tianchiensis Li & Chen, sp. n., S. (S.) cavatus Li & Chen, sp. n., and S. (S.) nigriclypeus Li & Chen, sp. n. The following four species are newly recorded from China: Symmorphus (S.) fuscipes (Herrich-Schaeffer), S. (S.) lucens (Kostylev), S. (S.) sublaevis Kostylev, and S. (S.) violaceipennis Giordani Soika. In addition, we map the species geographical distributions in China of these 19 species. Type specimens of these three new species are deposited in Chongqing Normal University and Yunnan Agricultural University.  相似文献   

13.
The Malagasy giant pill-millipede genus Sphaeromimus de Saussure & Zehntner, 1902 is revised. Seven new species, S. titanus sp. n., S. vatovavy sp. n., S. lavasoa sp. n., S. andohahela sp. n., S. ivohibe sp. n., S. saintelucei sp. n., and S. andrahomana sp. n. were discovered, in one case with the help of sequence data, in the rainforests of southeastern Madagascar. The species are described using light- and scanning electron microscopy. A key to all 10 species of the genus is presented. All but one (S. andohahela) of the newly discovered species are microendemics each occurring in isolated forest fragments. The mitochondrial COI barcoding gene was amplified and sequenced for 18 Sphaeromimus specimens, and a dataset containing COI sequences of 28 specimens representing all Sphaeromimus species (except S. vatovavy) was analyzed. All species are genetically monophyletic. Interspecific uncorrected genetic distances were moderate (4–10%) to high (18–25%), whereas intraspecific variation is low (0–3.5%). Sequence data allowed the correct identification of three colour morphs of S. musicus, as well as the identity of a cave specimen, which although aberrant in its morphology and colouration, was genetically identical to the holotype of S. andrahoma.  相似文献   

14.
A reappraisal of the Scaridiidae (Rotifera, Monogononta)   总被引:2,自引:0,他引:2  
  相似文献   

15.
记述釆自云南省怒江峡谷地区短翼蚱科2新种,即突眼狭顶蚱Systolederus oculatus sp.nov.及高黎贡山波蚱Bolivaritettix gaoligongshanensis sp.nov.。突眼狭顶蚱近似于广西狭顶蚱Systolederus guangxiensis Zheng etJiang,1998及峨眉狭顶蚱Systolederus emeiensis Zheng,1998。突眼狭顶蚱与两种的区别为:1)侧面观前胸背板上缘平直;2)前胸背板后突到达后足胫节顶末端;3)雌性下生埴板后缘具3齿;4)后足胫节黑色,具淡色环。区别于广西狭顶蚱为:1)前胸背板前缘中央微凹;2)肩部之间不具1对短纵隆线。其又区别于峨眉狭顶蚱为:1)前胸背板中隆线全长明显;2)后翅到达后突的顶末端。高黎贡山波蚱近似于九万山波蚱Bolivaritettix juwanshanensis Zheng,2005及宽顶波蚱Bolivaritettix lativertex Brunner von Wattenwyl,1893。主要区别于二者为:1)颜面隆起纵沟宽狭于触角基节宽;2)肩角圆形;3)后突到达后足胫节2/3处;4)中足股节宽狭于前翅宽;5)后足股节上侧中隆线后段具3个突起。其又区别于九万山波蚱为:1)头顶宽为1眼宽的1.5倍;2)侧面观前胸背板上缘平直;3)后翅到达后突顶末端。  相似文献   

16.
Fend  Steven V.  Gustafson  Daniel L. 《Hydrobiologia》2001,463(1-3):13-22
Secubelmis limpida n. sp., n. gen., is described from Montana, U.S.A. The monotypic genus resembles the lumbriculid genera Rhynchelmis and Tatriella in having atria in X, spermathecae in VIII, and semi-prosoporous male ducts. It differs from Tatriella in having paired atria and spermathecae, and from Rhynchelmis in having petiolate atria. The single prostate gland is unique within the Lumbriculidae. The new species appears to have a restricted range in the northern Rocky Mountains.  相似文献   

17.
The first record of the Cape hagfish Myxine capensis in Mozambican waters is reported based on a single 356 mm total length specimen taken by bottom trawl off Maputo, 25° 52·9' S; 34° 42·7' E - 25° 54·1' S; 34° 41·0' E, at depths from 557 to 564 m. This account also represents the northernmost record of a hagfish in the western Indian Ocean. Morphometric and meristic data are provided and compared with those of 27 specimens (including the holotype) caught off Namibia and South Africa.  相似文献   

18.
Eight new species of the genus Spathius Nees from Japan and the Russian Far East are described and illustrated: S. enigmatus sp. n., S. ishigakus sp. n., S. konishii sp. n., S. multigranulatus sp. n., S. omotodakus sp. n., S. pseudaspersus sp. n., S. pumilio sp. n., and S. tsushimus sp. n.  相似文献   

19.
The genus Cales (Hymenoptera: Aphelinidae) includes 13 species worldwide, of which 10 form a highly morphologically uniform species complex with a native range in the Neotropical region. We recognize ten species previously attributed to a single Neotropical species, Cales noacki Howard, which in the strict sense is a species broadly disseminated to control woolly whitefly. A neotype is designated for C. noacki, and it is redescribed based on specimens molecularly determined to be conspecific with the neotype. Newly described species include: C. bicolor Mottern, n.sp ., C. breviclava Mottern, n.sp ., C. brevisensillum Mottern n.sp ., C. curvigladius Mottern, n.sp ., C. longiseta Mottern, n.sp ., C. multisensillum Mottern n.sp ., C. noyesi Mottern, n.sp ., C. parvigladius Mottern, n.sp . and C. rosei Mottern, n.sp . Species are delimited based on a combination of morphological and molecular data (28S‐D2 rDNA and COI). Additional specimens are included in the phylogenetic analyses and although these likely represent several new species, we lack sufficient specimen sampling to describe them at this time. Cales are highly morphologically conserved and character‐poor, resulting in several cryptic species. A molecular phylogeny of the known Neotropical species based on 28S‐D25 rDNA and a 390‐bp segment of COI is included, and identification keys to males and females are provided. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:7FEB0479‐9B2E‐48E8‐8603‐4B7C2759D4EC .  相似文献   

20.
Thermopsis thermophila n. gen. n. sp., a new freshwater ostracod species is described from hot springs in Nevada, U.S.A. The animals were collected within a temperature range of 40–55°C. The new genus belongs to the Ostracoda Podocopida Cypridoidea Cyprididae Cypridopsinae.  相似文献   

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