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1.
Reinhard Berndt 《Plant Systematics and Evolution》1996,200(1-2):79-88
A new rust fungus,Spumula serispora, is described. The morphology of the teliospores and the telia was studied. In the teliospores ofS. serispora andS. quadrifida, the type species of the genus, sterile cells could be found, which are comparable to apical cells of otherRaveneliaceae. Similar sterile cells were also present in the telial heads ofRavenelia texensis. The ontogeny of the teliospores ofS. serispora and the teliospore heads ofRavenelia texensis was studied and compared. In both species the ontogeny of the spores heads was similar. InR. texensis hygroscopic cysts sustaining the spore heads were produced by division and not by conversion of basal sterile cells of the teliospore heads.Part 114 of the series Studies inHeterobasidiomycetes. 相似文献
2.
The genus Thetidos was established to accommodate a single species Thetidos morsura, a minute turriform conoidean with an unremarkable paucispiral protoconch, but possessing characteristic globose whorls of the teleoconch and three strong denticles on the inside of outer apertural lip. Subsequently, Thetidos was considered synonymous with Lienardia, and has rarely been mentioned in literature until the recent discovery of a remarkably similar species Thetidos tridentata, though it is different in protoconch morphology. Both molecular data and protoconch morphology unequivocally suggested placement of the new species in Raphitomidae. Examination of shells from the Indo-Pacific identified a number of similar forms, all referable to the genus Thetidos. Six species are now recognized within the genus; of them three, Thetidos puillandrei n. sp., Thetidos minutissima n. sp., Thetidos pallida n. sp., are here described as new. Thetidos species are now known from subtidal depths from the Philippines and Sulawesi to French Polynesia. Thetidos morsura is the only species of the genus that possesses a paucispiral protoconch suggestive of a non-planktotrophic development, although it displays a wide geographic range and a high morphological variability.
http://zoobank.org/urn:lsid:zoobank.org:pub:1F2001CC-6BEA-4B26-AFB8-6B337E101FDB 相似文献
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4.
The musculature in the rotifer species Proales daphnicola, P. reinhardti and P. fallaciosa was stained with phalloidin-labeled fluorescent dye and compared using confocal laser scanning microscopy. All three species share several homologous muscle systems, but each systems detailed morphology varies among the species both concerning appearance, number and location. The obtained results were compared with data from other rotifers and it was concluded that the muscles pars coronalis and the corona sphincter probably represent conditions in Ploima or Monogononta, while incomplete circular muscles and dorsal and ventral trunk retractors might be part of the eurotatorian ground pattern. 相似文献
5.
Karyotype evolution and sex chromosome differentiation in schistosomes (Trematoda,Schistosomatidae) 总被引:5,自引:0,他引:5
The morphology of C-banded metaphase chromosomes has been studied in two hermaphroditic and ten gonochoristic digenetic trematodes (schistosomes). Comparison of numbers and morphology of chromosomes indicates that the karyotype of primitive trematodes probably was composed of 10 (or 11) pairs of telocentric or subtelocentrie chromosomes, and reduction of chromosome numbers in advanced species resulted from centromeric fusion rather than elimination of chromosomes. Observation of heteromorphic chromosomes in a hermaphroditic trematode (Spirorchis) suggested a differentiation of pre-sex chromosomes in species ancestral to dioecious trematodes which possess distinctly differentiated sex chromosomes. Our results indicate that differentiation of Z and W chromosomes in the gonochoristic trematodes resulted from: (a) partial constitutive heterochromatinization of the W chromosome (Schistosoma mansoni and S. haematobium complexes, African schistosomes), (b) deletion of part of the W (S. japonicum and S. mekongi, Asian schistosomes), and (c) translocation of part of one sex chromosome onto another (Schistosomatium douthitti and Heterobilharzia americana, American schistosomes) with subsequent heterochromatinization of the W in H. americana. 相似文献
6.
Scott W. Johnson Michael L. Murphy David J. Csepp 《Environmental Biology of Fishes》2003,66(3):259-270
We examined distribution, habitat, and behavior of rockfishes, Sebastes spp., with a remotely operated vehicle (ROV) in coastal waters <90m deep of southeastern Alaska from 1998 to 2000. We identified black, S. melanops, canary, S. pinniger, China, S. nebulosus, copper, S. caurinus, dusky, S. ciliatus, harlequin, S. variegatus, Puget Sound, S. emphaeus, quillback, S. maliger, redstripe, S. proriger, rosethorn, S. helvomaculatus, silvergray, S. brevispinis, tiger, S. nigrocinctus, yelloweye, S. ruberrimus, and yellowtail, S. flavidus, rockfish. Quillback and dusky rockfish were the most widely distributed species, China and harlequin rockfish were the least widely distributed species. Species richness was greater at sites on or near the outer coast than at sites in more inside, sheltered waters. Most (>75%) observations of rockfish were over complex bottoms of boulder and rock or in vertical bedrock wall habitats. Few rockfish were observed over soft bottoms with no relief. Median depth of observation was 30m for black, copper, dusky, and yellowtail rockfish and >30m for all other species. Median temperature of observation ranged from 6.1°C for harlequin rockfish to 9.4°C for black rockfish. Size of fish was positively correlated (p 0.036) with depth for dusky, quillback, and yelloweye rockfish. Species often observed alone were China (67%), copper (46%), quillback (46%), and rosethorn (43%) rockfish. Most (70%) observations of harlequin, Puget Sound, silvergray, tiger, and yelloweye rockfish were in mixed species assemblages. When first observed, the behavior of most rockfish species was swimming or hovering. Notable exceptions were China, harlequin, rosethorn, and tiger rockfish; 33–57% were resting on bottom or in a hole or crevice. 相似文献
7.
Isozymes, vegetative and reproductive morphology, seasonality, vertical and geographic distributions and chromosomes were compared for six pairs of putative sibling species of Porphyra (P. abbottae/P. torta, P. fallax subsp. fallax/P. fallax subsp. conwayae, P. amplissima/P. cuneiformis, P. fucicola/P. leucostica, P. miniata/P. variegata, P. umbilicalis/P. umbilicalis) and among five species in a complex (P. brumalis, P. kurogii, P. linearis, P. pseudolinearis, and P. purpurea.) Geographic distribution and zymograms for certain proteins showed the greatest change between species pairs: only one pair of species had identical distributions, and most species pairs were disjunct; every species had a different allozyme for GOT-1, whereas all species had apparently identical proteins for phycoerythrin. Seasonality and habitat exhibited moderate differentiation: Northeast Pacific sibling species were characterized by a high intertidal winter species pairing with a mid intertidal spring species, whereas all but one of the other species pairs exhibited nearly identical vertical distributions and seasonalities. There were few changes in morphology: most species pairs had essentially identical morphologies and coloration and the same arrangement of reproductive cells. Chromosome numbers and karyotypes were identical for species pairs and in the species complex. These results provide evidence for different rates of evolution of different characters in the genus Porphyra. 相似文献
8.
In the Northeast and the Northwest Pacific, 26 and 68 species of Sebastes occur, respectively, the similar appearance of some pairs of shallow coastal water species in the two regions having been interpreted as evidence either for migration of ancestral species or of morphological convergence. To distinguish between these competing hypotheses, a portion of the mitochondrial DNA (mtDNA) cytochrome b gene was sequenced from 23 species of Sebastes from the Northwest Pacific and phylogenetic trees constructed so as to include the existing data from Northeastern species of Sebastes. The results clearly indicated separate origins for external morphology in Northeast and Northwest Pacific species. The shallow coastal water species in the Northwest Pacific are thought to have diverged from about 9.8MYA. Furthermore, the phylogenetic position of Sebastes was inferred among the subfamily Sebastinae, Helicolenus, Hozukius, Sebastes, and Sebastiscus, the results suggesting that Helicolenus and Hozukius are more closely related to Sebastes than Sebastiscus. 相似文献
9.
<Emphasis Type="Italic">Aspergillus vadensis</Emphasis>, a new species of the group of black Aspergilli 总被引:2,自引:0,他引:2
de Vries RP Frisvad JC van de Vondervoort PJ Burgers K Kuijpers AF Samson RA Visser J 《Antonie van Leeuwenhoek》2005,87(3):195-203
A strain from the group of black Aspergilli was analysed in detail to determine the species to which it belongs. A detailed analysis of morphology, RFLP patterns and metabolite profiles was carried out. In addition, a phylogenetic tree was constructed for the black Aspergilli using the ITS and the -tubulin sequences of the individual strains. The new species differs by its poor growth on glycerol and galacturonate and its unique extrolite profile consisting of aurasperone B, nigragillin, asperazine and kotanins. RFLP analysis using three genes as probes also resulted in a unique pattern. These data indicate that the strain was closely related but not identical to Aspergillus foetidus, Aspergillus niger and Aspergillus tubingensis. It was therefore designated as a novel species and named Aspergillus vadensis. 相似文献
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K. Kazan J. M. Manners D. F. Cameron 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1993,85(6-7):882-888
Summary Random amplified polymorphic DNA (RAPD) markers were generated from 20 cultivars and accessions representing four agronomically important species of Stylosanthes, S. scabra, S. hamata, S. guianensis, and S. humilis. Approximately 200 fragments generated by 22 primers of arbitrary sequence were used to assess the level of DNA variation. Relatively low levels of polymorphism (0–16% of total bands in pairwise comparisons) were found within each species, while polymorphisms between the species were much higher (up to 46%). Very few polymorphisms (0–2%) were detected between the individuals of the same cultivar or accession. A phenogram of relationships among the species was constructed based on band sharing. Four main clusters corresponding to each species were readily distinguished on this phenogram. The allotetraploid species S. hamata and its putative diploid progenitor, S. humilis, were more similar to each other than to S. scabra and S. guianensis. No variation in RAPD markers was found between the two commercial S. hamata cvs Verano and Amiga. Cultivar Oxley in S. guianensis was considerably different from the other cultivars and accessions of this species. The phylogenetic distinctions obtained with RAPDs were in agreement with other studies from morphology, cytology, and enzyme electrophoresis. The low level of polymorphisms observed within each species suggested that interspecific crosses may be a better vehicle for the construction of RAPD linkage maps in Stylosanthes. 相似文献
12.
David U. Hernández-Becerril 《Plant Systematics and Evolution》1992,181(3-4):217-226
Two new planktonic diatom species of the genusChaetoceros are described herein:Ch. octagonus andCh. rectus, from material of Baja California coasts and the Gulf of California, respectively;Ch. rectus was also found in a sample from Australian waters.Ch. octagonus is a robust species, with a characteristic pyramidal valve shape, heavily silicified valves and setae, and one central rimoportula on every valve in the chain; it is compared with related species, which show a similar morphology, especially by electron microscopy. It belongs into subg.Chaetoceros, sect.Borealia. Ch. rectus is placed in subg.Hyalochaete, and provisionally within sect.Anastomosantia. Its major characters are: chains, cells, and setae are delicate and fragile, cells are joined in the chain by a bridge which connects sibling intercalary setae, valves and setae are weakly silicified, and one rimoportula is present on terminal valves only. Comparison is made with another species of the same section.Ch. rectus shows a different manner of chain-forming within the genus than previously described in the literature. 相似文献
13.
Hybridization is increasingly recognized as a significant creative force in evolution. Interbreeding among species can lead to the creation of novel genotypes and morphologies that lead to adaptation. On the Hawaiian island of Oahu, populations of two species of plants in the endemic genus Lipochaeta grow at similar elevations in the northern Waianae Mountains. These two species represent extremes of the phenotypic distribution of leaf shape: the leaves of Lipochaeta tenuifolia individuals are compound and highly dissected while leaves of L. tenuis are simple. Based primarily on leaf shape morphology, a putative hybrid population of Lipochaeta located at Puu Kawiwi was identified. Individuals in this population exhibit a range of leaf shapes intermediate in varying degrees between the leaf shapes of the putative parental species. We analyzed individuals from pure populations of L. tenuifolia, L. tenuis and the putative hybrids using 133 AFLP markers. Genetic analysis of these neutral markers provided support for the hybrid origin of this population. The correlation between genetic background and leaf morphology in the hybrids suggested that the genome of the parental species with simple leaves might have significantly contributed to the evolution of a novel, compound leaf morphology. 相似文献
14.
Alexei V. Chernyshev Neonila E. Polyakova Sergei V. Turanov Hiroshi Kajihara 《分类学与生物多样性》2018,16(1):55-68
The heteronemertean genus Lineus Sowerby, 1806 has been badly in need of revision because of its apparent non-monophyly. In this paper, we focus on Lineus torquatus Coe, 1901, one of the heteronemertean species that occur commonly in waters around the North Pacific, as well as a few other allied species distributed in the western North Pacific, including Lineus alborostratus Takakura, 1898 and Cerebratulus montgomeryi Coe, 1901. Based on phylogenetic analyses using 16S, COI, 28S, 18S, and H3 gene and ITS sequences, we detected a well-supported clade comprised of heteronemerteans with a frontal white band on the head, to which we add Kulikovia gen. nov. This genus is nested within a more comprehensive, highly supported clade, here named the Siphonenteron-clade, which contains Tenuilineus bicolour (Verrill, 1892), Lineus flavescens Coe, 1905, Siphonenteron bilineatum (Renier, 1804), S. cf. bilineatum, Lineus cf. caputornatus, and Lineus sp. from Guam. Our analyses confirmed the presence of a cryptic species of what was formerly known as the cherry-red and reddish forms of Lineus torquatus, herein described as Kulikovia manchenkoi sp. nov. based on some external characters, internal morphology, and the four genetic markers (COI, 16S, H3, and ITS). In contrast to the species pair K. torquata–K. manchenkoi, the reddish form of K. alborostrata does not differ genetically from the typical form of this species. The significance of the external and internal characters for distinguishing cryptic species is discussed.
http://zoobank.org/urn:lsid:zoobank.org:pub:9BECBC60-9C82-48EC-AD36-FC564D82A5BChttp://zoobank.org/urn:lsid:zoobank.org:act:D02B2339-4F65-4517-9B13-DD4AAB0C55C5http://zoobank.org/urn:lsid:zoobank.org:act:8D239B62-E655-4721-90F0-A4944DD8A3C7 相似文献
15.
SEM morphological survey on the egg shell in the italian Anostracans (Crustacea,Branchiopoda) 总被引:5,自引:5,他引:0
Graziella Mura 《Hydrobiologia》1986,134(3):273-286
The screening of the egg shell morphology of all italian species of Anostracans (14) by means of SEM, as well as the analysis of preliminary data on electrophoretical patterns of the adults, concerning the genus Chirocephalus (five species), suggest the need for a reconsideration, from a taxonomical point of view, especially as far as the species of the diaphanus group (Ch. diaphanus, Ch. ruffoi, Ch. salinus, Ch. sibyllae) are concerned.In this light, within the above mentioned group remarkable differences have been observed for Ch. ruffoi, whilst for other species like Ch. diaphanus and Ch. sibyllae, conspecificity is suspected. Electrophoretical and reproductive isolation studies, in progress, will provide a clearer understanding of the actual situation.Research carried out with M.P.I. (60%) and C.N.R. (chBr. 83.02549.04 Gruppo di Biologia Naturalistica) financial support.Research carried out with M.P.I. (60%) and C.N.R. (chBr. 83.02549.04 Gruppo di Biologia Naturalistica) financial support. 相似文献
16.
Conchospore production and seasonal occurrence of some Porphyra species (Bangiales,Rhodophyta) in Washington State 总被引:1,自引:1,他引:0
The leafy thalli of species of the marine red algal genus Porphyra grow rapidly but persist for a relatively short time on rocky intertidal or subtidal substrata or as epiphytes on other marine plants. In most species, the large, short-lived leafy thalli alternate with small, presumably perennial, filamentous conchocelis plants. Depending on the species of northeastern Pacific Porphyra, photoperiod and temperature are important regulators of conchospore formation and release. Data from laboratory studies of conchospore formation and release in five Washington species of Porphyra (P. abottae, P. nereocystis, P. perforata, P. pseudolanceolata and P. torta) indicate that conchospores are most likely to be released at a time that precedes the appearance of the leafy thalli in the field. 相似文献
17.
Paul Mahlberg 《Planta》1973,110(1):77-80
Summary The morphology of starch grains isolated from the latex of 2 species of Euphorbia was compared by scanning electron microscopy. In E. terracina they are elongated and greater, in diameter at the midregion than at the tips while in E. tirucalli they are osteoid. Starch grains varied in size in both, species although in E. tirucalli the largest grains, which measured 49 , were approximately twice the length of those in E. terracina (27 ). 相似文献
18.
East African and south African churchills (Petrocephalus, Mormyridae) were synonymised in 1959 to become members of a single species of subcontinental, southern African distribution, Petrocephalus catostoma (Günther, 1866). By comparison with the type material for P. catostoma from the Ruvuma River and P. stuhlmanni from the Ruvu River, both of East African origin, we confirm the South African form of churchill to represent a new species, P. wesselsi, ranging from the northern Limpopo and Incomati systems south to the Pongola River (Natal) as its southern limit. We also compared churchills from the Sabie River (25° S, South Africa, Incomati system) with churchills from the Upper Zambezi River (17° S, Namibia), using electric organ discharges (EODs) and morphology. The duration of an EOD pulse of the South African form (N = 39; 943.2±S.E. 18.82µs) is, on average, more than twice that of the Upper Zambezi form (N = 37; 436.6±15.1µs), and the amplitude of the second head-positive phase (P2 phase relative to P1 = 1) significantly weaker (0.133 ± 0.0005 vs. 0.472 ± 0.002 for Upper Zambezi males, 0.363 ± 0.03 for Upper Zambezi females). In contrast to the Upper Zambezi form, the EOD of the South African form exhibits no difference between the sexes. Fish from the two origins differ significantly in 11 out of 14 anatomical characters studied, confirming molecular genetic differentiation on the species level. 相似文献
19.
C. Hartmann M. Winfield F. Corre M. R. Davey A. Rode A. Karp 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1996,93(5-6):968-974
Southern-blot hybridizations of total DNA to mitochondrial DNA (mtDNA) probes were used to investigate the extent of mtDNA variability in cultures derived from immature embryos of diploid (Triticum monococcum, genomic formula: AA, T. tauschii, genomic formula: DD), allotetraploid (T. durum cv Creso, genomic formula: AABB), and allohexaploid (T. aestivum, genomic formula: AABBDD) wheat species. Similar distinct changes in mtDNA organization were observed in in vitro cultures of the derived tetraploid and the hexaploid species with related genomes. The tetraploid and hexaploid species share the B genome and mtDNA variability in in vitro culture is known to be under nuclear control. These results suggest that a study of B genome diploids and other polyploid combinations would now shed light on whether or not mtDNA variability in tissue cultures is under B-genome control. 相似文献
20.
Frary A Fritz LA Tanksley SD 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2004,109(3):523-533
In an effort to better understand the dramatic differences in vegetative and floral morphology that differentiate species within the genus Lycopersicon, quantitative trait loci (QTL) for leaflet and perianth size and shape characters were mapped in an interspecific F2 population of tomato (Lycopersicon esculentum × L. pennellii). Thirty-six highly significant (P0.001) QTL were associated with 18 separate traits. QTL for correlated traits were generally not colocalized in the genome unless there was a clear codependence between the traits (e.g., organ length and area). Little or no overlap in QTL positioning between different organs was observed, suggesting that the genes determining the size and shape of leaflets, sepals, and petals are organ specific. Thus, while leaves are considered the developmental and evolutionary precursors to floral organs, genes acting late in development to determine certain aspects of morphology (namely shape and size) must have specialized to exert control over individual organs. Five of the leaflet-trait QTL map to analogous regions in the genome of eggplant, and therefore it appears there has been some conservation in the genes controlling leaf morphology within the Solanaceae. 相似文献