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1.
The living morphology, infraciliature, morphogenesis and phylogenetic position of a new hypotrichous ciliate, Heterourosomoida sinica n. sp., discovered in saline soil in Northwest of China, were investigated. Heterourosomoida sinica n. sp. is characterized as follows: body size about 70–95 × 20–30 μm in vivo, ellipsoid or elongate; cortical granules dark green, 0.5 μm across, arranged around dorsal cilia and in short irregular rows on ventral side; consistently 18 frontoventral-transverse cirri; left and right marginal rows composed of 17–24 and 13–21 cirri, respectively; two macronuclear nodules and one or two micronuclei. The detailed morphogenesis of a species of Heterourosomoida is reported for the first time. The ontogenesis on dorsal side is basically similar to that in Urosomoida-species and the process on ventral side is characterized by: 18 frontoventral-transverse cirri develop from six anlagen with the anlagen V and VI formed in the primary mode. Phylogenetic analyses based on SSU rDNA sequence data reveal that Heterourosomoida sinica n. sp. clusters with Kleinstyla dorsicirrata and forms a clade with the type species H. lanceolata.  相似文献   

2.
The morphology, infraciliature, and molecular phylogeny of two novel spirotrich ciliates, Caryotricha rariseta n. sp. and Discocephalus pararotatorius n. sp., isolated from coastal waters of China, were investigated. Caryotricha rariseta n. sp. differs from its congeners mainly in possessing seven sparsely ciliated cirral rows that are conspicuously shortened posteriorly and three transverse cirri aligned in a row. Discocephalus pararotatorius n. sp. is characterized by the conspicuous spine‐like dorsal cilia, one extra (endoral?) membrane, and seven frontal, six ventral, and seven posterolateral marginal cirri. The small subunit rRNA gene was sequenced for both species. Complete SSU rRNA gene sequences of two Caryotricha spp. (including C. rariseta n. sp.) and two Discocephalus spp. (including D. pararotatorius n. sp.), along with those of 40 other ciliates, were used to determine their molecular phylogeny using maximum likelihood, neighbor joining and maximum parsimony analyses. The two Caryotricha species cluster with Kiitricha marina in the well‐supported Protohypotrichia clade that is basal to the main spirotrich assemblage. The two discocephalids form a clade that is sister to the Hypotrichia.  相似文献   

3.
Two marine urostylid ciliates, Caudiholosticha marina sp. nov. and Nothoholosticha flava sp. nov., isolated from intertidal sediment in the Yellow Sea, are investigated using morphological and small subunit rDNA phylogenetic analyses. Caudiholosticha marina is 210?310 μm × 40?55 μm in vivo, and has 10?20 macronuclear nodules, 23?37 midventral cirral pairs extending to 5?8 transverse cirri, and two caudal cirri. It differs from congeners by its marine habitat, larger size, macronuclear arrangement pattern and high number of midventral pairs. Molecular phylogenetic analyses indicate a polyphyly of Caudiholosticha. Nothoholosticha flava is yellow to brownish and 240?320 μm × 40?60 μm sized, and has a bipartite adoral zone, six frontal cirri in atypical bicorona, usually four frontoterminal, one buccal and 5?7 transverse cirri and 28?54 midventral pairs. Phylogenetic analyses allocate N. flava as sister of N. fasciola, type of the genus. The two Nothoholosticha species differ distinctly by the presence/absence of frontoterminal cirri, a feature often used to define genera in the Hypotrichia. However, the SSU rDNA sequence similarity between these two species is 99.3%, which weakens the justification for separating the new isolate at genus level. The taxonomic significance of frontoterminal cirri is discussed based on morphological and molecular data.  相似文献   

4.
This paper investigates the morphology, morphogenesis and SSU rRNA gene-based phylogeny of Apoholosticha sinica n. g., n. sp., isolated from mangrove wetland in Shenzhen, southern China. The new genus Apoholosticha is characterized by its bipartite adoral zone, clearly differentiated frontal cirri arranged in a bicorona, midventral complex composed of midventral pairs only, one marginal cirral row on each side, presence of frontoterminal and transverse cirri, and the lack of a buccal cirrus and caudal cirri. The type species, Apoholosticha sinica n. sp. is diagnosed by the elongated body shape and two kinds of cortical granules. Its main morphogenetic features are similar to that of Pseudokeronopsis except for (1) no buccal cirrus is formed and (2) its macronuclear nodules fuse into a single mass during cell division. Phylogenetic analyses for the new taxon indicate that Apoholosticha n. g. is most closely related to Nothoholosticha and Heterokeronopsis, and falls into the family Pseudokeronopsidae within the core Urostylida clade. In addition, a species that had been misidentified in previous literature is here recognized and assigned to the new genus as Apoholosticha sepetibensis (Wanick and Silva-Neto, 2004) n. comb. (basionym: Pseudokeronopsis sepetibensis Wanick and Silva-Neto, 2004).  相似文献   

5.
The morphology and molecular phylogeny of a soil hypotrich ciliate, Pseudourostyla guizhouensis sp. nov., collected from southern China, were investigated. Pseudourostyla guizhouensis sp. nov. has an elongate elliptical body measuring 180–310 × 65–85 μm in vivo; invariably two right and three or four left marginal rows; six or seven dorsal kineties; adoral zone consisting of 57–70 membranelles; 12–16 frontal cirri, one buccal cirrus, 13–20 midventral pairs, two frontoterminal cirri, two pretransverse cirri, and five to seven transverse cirri. Morphogenesis during physiological regeneration indicates that the marginal rows of each side originate from a common anlage that differentiates into several rows. Molecular phylogenetic analysis based on SSU rDNA sequence data reveals that Pguizhouensis sp. nov. clusters with the type species P. cristata (Jerka‐Dziadosz, 1964) Borror, 1972 and that the genus Pseudourostyla is monophyletic. The morphological characters of another soil hypotrich ciliate, Hemicycliostyla franzi (Foissner, 1987) Paiva et al., 2012, are also described based on a Chinese (Guizhou) population.  相似文献   

6.
Two novel hypotrichous ciliates, Hemiurosomoida warreni nov. spec. and Hemiurosoma clampi nov. spec., isolated from soil in the Lhalu Wetland and Motuo Virgin Forest in Tibet, respectively, were investigated using live observation and protargol staining. Hemiurosomoida warreni nov. spec. strongly resembles the type species H. longa but can be distinguished by its body size in vivo (110–145 × 30–40 μm vs. 50–100 × 18–40 μm), number of adoral membranelles (25–38 vs. 15–22), and numbers of right (29–39 vs. 14–23) and left (26–35 vs. 13–23) marginal cirri, transverse cirri (3 vs. 4 or 5) and macronuclear nodules (4–8 vs. 2). Hemiurosoma clampi nov. spec. is characterized by its vermiform body shape, colourless cortical granules distributed in irregular rows, two macronuclear nodules, three frontal cirri, one buccal cirrus, four frontoventral cirri ranged in a line, two transverse cirri, lacking postoral ventral and pretransverse ventral cirri, and marginal rows that are not posteriorly confluent. Phylogenetic analyses based on SSU rDNA gene sequences suggest that Hemiurosomoida is not monophyletic. A close relationship is revealed between Hemiurosomoida warreni nov. spec., Parakahilella macrostoma, Hemiurosoma clampi nov. spec., and the type species Hemiurosoma terricola. As expected, all these species are classified within the “non-oxytrichid Dorsomarginalia”.  相似文献   

7.
A new flagellate of the Raphidophyceae, Chlorinimonas sublosa gen. et sp. nov., collected from Wakayama Prefecture, Japan is described based on morphological observations, microspectrophotometry of chloroplasts, and phylogenetic analysis of SSU rDNA sequences. The cell was usually elliptical, sometimes spherical, oval or slender, and possessed two subequal heterodynamic flagella emerging from a subapical pit. Greenish yellow discoidal chloroplasts, 15–25 per cell, were situated at the periphery of the cell. The alga is very similar to the genus Heterosigma, but distinct in that there is no invagination of thylakoids into the pyrenoids and no typical girdle lamella in the chloroplast, and the chloroplasts are greenish yellow. Phylogenetic analysis of SSU rDNA revealed that this alga forms a sister clade with the clade of Chattonella and Heterosigma. Based on these results, we propose a new genus Chlorinimonas with Chlorinimonas sublosa as the type species. In addition, this paper is the first report of molecular data covering all genera of the Raphidophyceae. The phylogenetic analysis suggests that the intrusion to freshwater habitat has occurred only once in the Raphidophyceae.  相似文献   

8.
In a study on ciliate diversity, we discovered the new hypotrich species, Gonostomum jangbogoensis n. sp., in freshwater from Terra Nova Bay, Victoria Land, southeast Antarctica. We describe its morphology and morphogenesis using standard methods, and the SSU rRNA gene phylogeny is provided as well. Morphology of Gonostomum jangbogoensis n. sp. is characterized as follows: slender to elongated body shape; grayish under low magnification; cortical granules present; 32–41 adoral membranelles; 3 enlarged frontal cirri; 1 buccal cirrus; 2 frontoterminal cirri; 3 or 4 frontoventral cirral pairs, 2 pretransverse cirri, 6–7 transverse cirri; 13–19 left and 18–26 right marginal cirri; 17–23 paroral kinetids; 3 dorsal kineties; 3 caudal cirri; 2 macronuclear nodules with 1–3 micronuclei. The morphogenesis of the new species confirms that it has at least seven frontal-ventral-transverse cirral anlagen, which is also reported in Gonostomum sp. 1 sensu Shin from Korea. Even though these two populations occur very far from each other, the morphometric data prove that this character state, the seven cirral anlagen, is a stable feature across these populations and might be an apomorphy. The phylogenetic analyses show that the genus Gonostomum is non-monophyletic and that the new species is a sister to G. bromelicola.  相似文献   

9.
Two new species of the red algal genus Predaea are described from Australia. The first, Predaea aurora Kraft et G.W. Saunders, sp. nov., is unusual in its cool‐temperate distribution and in a number of anatomical attributes, most notably the rhizoid‐like habit of the nutritive filaments associated with the auxiliary cells. The second species, Predaea tumescens Kraft et G.W. Saunders, sp. nov., inhabits a coral reef habitat more typical of the genus but nonetheless differs in a number of anatomical details from other reported species. Nuclear small subunit rDNA sequences have confirmed the affinity of P. aurora to other species currently included in this genus. Molecular analyses further indicate that Predaea belongs in the Nemastomataceae and that the Nemastomataceae and Schizymeniaceae are sister taxa in an independent clade of “lineage 4” florideophyte algae. As such, a proposal is made to resurrect the Nemastomatales Kylin emend. G.W. Saunders et Kraft to accommodate these two families. Within the Schizymeniaceae, the Australian‐endemic Platoma australicum and Platoma foliosum were only distantly related to the other included Platoma, Schizymenia, and Titanophora spp. We therefore propose Wetherbeella G.W. Saunders et Kraft, gen. nov., to accommodate these two species. An additional outcome of our molecular analyses is that the genus Tsengia is not a member of the Nemastomataceae (where it is currently placed) but rather forms an independent lineage in the Halymeniales that we now designate as the Tsengiaceae G.W. Saunders et Kraft, fam. nov. Finally, the South African Nemastoma lanceolatum J. Agardh is transferred to Tsengia.  相似文献   

10.
Ambrosia beetles (Coleoptera: Scolytinae) are associated with strictly entomochoric and mutualistic fungi. We studied the mycobiota associated with Scolytodes unipunctatus, ambrosia beetles that infest Cecropia trees in Central America. Isolates were characterized using morphology and rDNA sequences (ITS region, LSU, and SSU rDNA). Four species are described here: Raffaelea scolytodis sp. nov. (Ophiostomatales), Gondwanamyces scolytodis sp. nov., Custingophora cecropiae sp. nov., and Graphium sp. (Microascales). The genus Custingophora is emended to include Knoxdaviesia anamorphs of Gondwanamyces based on uniformity of DNA sequences and phenotype.  相似文献   

11.
A taxonomic review of Japanese species of the creediid genusLimnichthys recognised the following:L. fasciatus, L. nitidus (a senior synonym ofL. donaldsoni) andL. orientalis sp. nov.L. fasciatus has an antitropical distribution.L. orientalis sp. nov. differs from its most similar congener,L. nitidus, in having fewer scales above and below the lateral line (2 vs. 3) and the fifth pelvic fin ray shorter or absent, and in the shape of cirri on the lower jaw.  相似文献   

12.
Two new species of Gracilariopsis from the Indian Ocean are proposed—Gracilariopsis (Gp.) mclachlanii Buriyo, Bellorin et M. C. Oliveira sp. nov. from Tanzania and Gracilariopsis persica Bellorin, Sohrabipour et E. C. Oliveira sp. nov. from Iran—based on morphology and DNA sequence data (rbcL gene and SSU rDNA). Both species fit the typical features of Gracilariopsis: axes cylindrical throughout, freely and loosely ramified up to four orders, with an abrupt transition in cell size from medulla to cortex, cystocarps lacking tubular nutritive cells and superficial spermatangia. Nucleotide sequence comparisons of rbcL and SSU rDNA placed both species into the Gracilariopsis clade as distinct species from all the accepted species for this genus, forming a deeply divergent lineage together with some species from the Pacific. The new species are very difficult to distinguish on morphological grounds from other species of Gracilariopsis, stressing the importance of homologous molecular marker comparisons for the species recognition in this character‐poor genus.  相似文献   

13.
Recent studies have revealed that the “lower” marine ciliates are far more diverse than previously suspected. During a survey on the ciliate fauna in coastal waters of Qingdao, northern China, we have isolated about 30 new or poorly known taxa. In the present study two colepid species are investigated, Nolandia orientalis spec. nov. and Pinacocoleps similis (Kahl, 1933) comb. nov. (basionym: Coleps similis Kahl, 1933). Their morphology and infraciliature are documented based on living observations and silver impregnations. The new species Nolandia orientalis differs from the type species N. nolandi mainly in the structure of tier plates. The structure of the tier plates was also the basis for transferring Coleps similis Kahl, 1933 to the genus Pinacocoleps and for three further new combinations: Pinacocoleps heteracanthus (Noland, 1937) comb. nov. (basionym: Coleps heteracanthus Noland, 1937), P. spiralis (Noland, 1937) comb. nov. (basionym Coleps spiralis Noland, 1937) and Pinacocoleps arenarius (Bock, 1952) comb. nov. (basionym: Coleps arenarius Bock, 1952).  相似文献   

14.
《Geobios》1988,21(4):465-493
The present paper describes 12 species of fish otoliths recovered by washing and screening processes from the Deccan Trap associated sedimentary (Intertrappean) beds exposed near Rangapur, Hyderabad District, Andhra Pradesh, India. The present collection of otoliths contains four major groups: Clupeomorpha (“Clupeidarum” sp.), Osteoglossomorpha (“Osteoglossidarum” deccanensis sp. nov., “O”. intertrappus sp. nov. and “Notopteridarum” nolfi sp. nov.), Protacanthopterygii (“Salmoniformorum” rectangulus sp. nov.), and Percomorpha (Dapalis sp., “Apigonidarum” ovatus sp. nov., “Serranidarum” sp., “Percoideorum” ellipticus sp. nov., “P.” rangapurensis sp. nov., “Percoideorum” sp. 1 and “Percoideorum” sp. 2). This collection of otoliths represents freshwater lacustrine deposition of the sediments. The age of the Intertrappean beds is considered Uppermost Cretaceous to Palaeoncene on the basis of freshwater ostracode (Paracypretta jonesi, Mongolianella hislopi and Candoniella sp.) and charophyte (Platychara perlata and Nemegtichara sp.) assemblages.  相似文献   

15.
16.
Two monospecific genera of marine benthic dinoflagellates, Adenoides and Pseudadenoides, have unusual thecal tabulation patterns (lack of cingular plates in the former; and no precingular plates and a complete posterior intercalary plate series in the latter) and are thus difficult to place within a phylogenetic framework. Although both genera share morphological similarities, they have not formed sister taxa in previous molecular phylogenetic analyses. We discovered and characterized a new species of Pseudadenoides, P. polypyrenoides sp. nov., at both the ultrastructural and molecular phylogenetic levels. Molecular phylogenetic analyses of SSU and LSU rDNA sequences demonstrated a close relationship between P. polypyrenoides sp. nov. and Pseudadenoides kofoidii, and Adenoides and Pseudadenoides formed sister taxa in phylogenetic trees inferred from LSU rDNA sequences. Comparisons of morphological traits, such as the apical pore complex (APC), demonstrated similarities between Adenoides, Pseudadenoides and several planktonic genera (e.g. Heterocapsa, Azadinium and Amphidoma). Molecular phylogenetic analyses of SSU and LSU rDNA sequences also demonstrated an undescribed species within Adenoides.  相似文献   

17.
The paraphyletic diatom genus Nitzschia comprises over 1000 morphologically distinct pennate taxa, known from the benthos and plankton of freshwater, brackish, and marine environments. The principal diagnostic characters for delimitation of Nitzschia species include valve shape, the position and structure of the raphe, presence/absence and shape of the proximal raphe endings and terminal raphe fissures, areola structure, and specific morphometric features such as cell size, and stria and fibula density. In this study, we isolated 12 diatom strains into culture from samples collected at the surface or greater depths of the southeastern Adriatic Sea. Morphological analyses included LM, SEM, and TEM observations, which, along with specific morphometric features, allowed us to distinguish three new Nitzschia species. These findings were congruent with the results of phylogenetic analyses performed on nuclear‐encoded SSU (18S) rDNA and chloroplast‐encoded rbcL and psbC genes. One of the new species (Nitzschia dalmatica sp. nov.) formed a lineage within a clade of Bacillariaceae containing members of the Nitzschia sect. Dubiae, which was sister to Psammodictyon. A second lineage was part of a novel clade that is significantly distinct from other Nitzschia species sequenced so far and includes Nitzschia adhaerens sp. nov. and N. cf. adhaerens. A further new species was found, Nitzschia inordinata sp. nov., which appeared as the sister group to the N. adhaerens clade and the conopeoid Nitzschia species in our phylogenetic trees. Our findings contribute to the overall diversity of genus Nitzschia, especially in identifying some deep branches within the Bacillariaceae, and highlight under‐scoring of this genus in marine plankton.  相似文献   

18.
The morphology and infraciliature of a new ciliate, Aspidisca hongkongensis spec. nov., a large marine form isolated from the coastal waters near Hong Kong, were investigated. It differs from the congeners by the combination of cell size (about 90×60 μm in vivo), 9–11 conspicuous dorsal ridges, one fine and seven strong frontoventral cirri, six membranelles in anterior portion of adoral zone, and 17–23 membranelles in posterior portion of adoral zone. The comparison with similar congeners clearly supports the distinction of this new species based on morphological and small subunit (SSU) rRNA gene sequence studies. The SSU rRNA gene sequence similarity within the genus is about 75.3–92.1% which indicates that this is a distinct form. Phylogenetic trees based on SSU rRNA gene information show that A. hongkongensis groups with A. leptaspis.  相似文献   

19.
Nuclear‐encoded SSU rDNA, chloroplast LSU rDNA, and rbcL genes were sequenced from 53 strains of conjugating green algae (Zygnematophyceae, Streptophyta) and used to analyze phylogenetic relationships in the traditional order Zygnematales. Analyses of a concatenated data set (5,220 nt) established 12 well‐supported clades in the order; seven of these constituted a superclade, termed “Zygnemataceae.” Together with genera (Zygnema, Mougeotia) traditionally placed in the family Zygnemataceae, the “Zygnemataceae” also included representatives of the genera Cylindrocystis and Mesotaenium, traditionally placed in the family Mesotaeniaceae. A synapomorphic amino acid replacement (codon 192, cysteine replaced by valine) in the LSU of RUBISCO characterized this superclade. The traditional genera Netrium, Cylindrocystis, and Mesotaenium were shown to be para‐ or polyphyletic, highlighting the inadequacy of phenotypic traits used to define these genera. Species of the traditional genus Netrium were resolved as three well‐supported clades each distinct in the number of chloroplasts per cell, their surface morphology (structure and arrangement of lamellae) and the position of the nucleus or nuclear behavior during cell division. Based on molecular phylogenetic analyses and synapomorphic phenotypic traits, the genus Netrium has been revised, and a new genus, Nucleotaenium gen. nov., was established. The genus Planotaenium, also formerly a part of Netrium, was identified as the sister group of the derived Roya/Desmidiales clade and thus occupies a key position in the evolutionary radiation leading to the most species‐rich group of streptophyte green algae.  相似文献   

20.
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