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1.
We studied the morphology of three rare haptorid ciliates, using live observation and silver impregnation: Apertospathula verruculifera n. sp., Longispatha elegans n. gen., n. sp., and Rhinothrix porculus (Penard, 1922) n. gen., n. comb. Simple ethanol fixation (50-70%, v/v) is recommended to reveal the ciliary pattern of "difficult" ciliates, such as R. porculus, by protargol impregnation. The three genera investigated have a distinct feature in common, viz., a lasso-shaped oral bulge and circumoral kinety, where the right half is slightly to distinctly longer than the left and the circumoral kinety is open ventrally. Thus, they are united in a new spathidiid family, the Apertospathulidae n. fam., which probably evolved from a Bryophyllum-like ancestor by partial reduction of the oral bulge and circumoral kinety. Apertospathula verruculifera has a wart-like process, the palpus dorsalis, at the anterior end of the dorsal brush. The right branch of the circumoral kinety is only slightly longer than the left one. Longispatha elegans has a straight oral bulge and circumoral kinety, the right branch of which extends to the posterior end of the body while the left branch ends in the anterior third of the body. Rhinothrix porculus, a curious ciliate with a snout-like dorsal elongation of the oral bulge, the palpus oralis, has a highly characteristic ciliary pattern: the oral pattern is as in Longispatha, but the bulge and circumoral kinety extend spirally to the posterior end of the body while the somatic kineties course meridionally. This is achieved by inserting some shortened kineties in the curves of the oral bulge.  相似文献   

2.
The morphology and infraciliature of the marine hypotrichous ciliate Nothoholosticha fasciola (Kahl, 1932) nov. gen., nov. comb., isolated from mariculture waters near Qingdao, China, are redescribed based on live and protargol-impregnated specimens. Features reported for the first time include the possession of more than 50 macronuclear nodules and details of the infraciliature, i.e. 50–60 adoral membranelles, shortened paroral and endoral membranes, six frontal, one buccal and two to seven transverse cirri, ca. 40 pairs of midventral cirri, ca. 60–120 left and 70–120 right marginal cirri, three dorsal kineties, caudal and frontoterminal cirri absent. In addition, brief details of two stages of cellular reorganization in N. fasciola are supplied and comparisons with some related urostylids based on SS rRNA gene sequence data are reported. The new genus Nothoholosticha is established based primarily on the absence of frontoterminal cirri, which distinctly separates it from similar urostylid genera. Anteholosticha longissima is transferred to Nothoholosticha as N. longissima (Dragesco and Dragesco-Kernéis, 1986) nov. comb. and Holosticha antarctica is transferred to Pseudokeronopsis as P. antarctica (Wilbert and Song, 2008) nov. comb.  相似文献   

3.
ABSTRACT. The planktonic ciliate genus Askenasia Blochmann, 1895 is reviewed and the new genus Rhabdoaskenasia n. gen. is established. Askenasia is characterized by three circumferential kinety belts and a circumoral wreath of paired argyrophilic granules without recognizable cilia and nematodesmata. A "brush" is absent. Askenasia apparently lacks the key characters of the Haptorida and is thus transferred to the Cyclotrichida, family Mesodiniidae. Rhabdoaskenasia differs from Askenasia in having single files of basal bodies in all kinety belts and club-shaped extrusomes. It possesses a circumoral kinety composed of dikinetids from which nematodesmata originate, forming a distinct rhabdos. Although very similar to Askenasia in its general appearance, R. minima n. sp. could belong to another order. Based on an extensive review of the literature and on silver impregnated specimens the following Askenasia species are recognized and described in detail: A. volvox (Eichwald, 1852) Kahl, 1930, A. stellaris (Leegaard, 1920) Kahl, 1930, A. acrostomia n. sp., and A. chlorelligera n. sp. Askenasia faurei Kahl, 1930 and A. humilis Gajewskaja, 1928 are transferred to the genus Cyclotrichium: C. faurei (Kahl, 1930) n. comb., C. humilis (Gajewskaja, 1928) n. comb. The systematic position of the genus Askenasia is discussed and keys to the genera of the Mesodiniidae and to the species of Askenasia are provided.  相似文献   

4.
Periphytic ciliates play a vital role in the material cycle and energy flow of microbial food web, however, their taxonomy and biodiversity are inadequately studied given their high species richness. Two new and one little known species, viz. Derouxella lembodes gen. et sp. nov., Cyrtophoron multivacuolatum sp. nov., and Cyrtophoron apsheronica Aliev, 1991, collected from coastal waters of China, were investigated using modern methods. Derouxella gen. nov. can be recognized by having dorsoventrally flattened body, a podite, one fragmented preoral kinety, two parallel circumoral kineties, and somatic kineties progressively shortened from right to left. Morphological classification and phylogenetic analyses based on nuclear small subunit ribosomal RNA (nSSU rRNA) and mitochondrial small subunit ribosomal RNA (mtSSU rRNA) gene sequence data inferred that Derouxella gen. nov. occupies an intermediate position between Hartmannulidae and Dysteriidae. Cyrtophoron multivacuolatum sp. nov. is characterized by large body size, the numbers of somatic kineties and nematodesmal rods, and having numerous contractile vacuoles. The genus Cyrtophoron and the poorly known species C. apsheronica were redefined. Even with the addition of newly obtained nSSU rRNA and mtSSU rRNA gene sequences of Cyrtophoron, the family Chlamydodontidae was still recovered as a monophyletic group, the monophyly of Cyrtophoron was supported too.  相似文献   

5.
The morphology and infraciliature of three soil gymnostome ciliates, Spathidium seppelti foissneri nov. subspec., Spathidium simplinucleatum nov. stat., and Dileptus americanus, collected from Slovakia, were investigated using live observation and protargol impregnation. S. seppelti foissneri is distinguished from its congeners by a combination of characters including: distinctly spatulate shape with convex oral bulge; 25 ellipsoidal, scattered macronuclear nodules; an average of 23 ciliary rows, 3 anteriorly differentiated to form a dorsal brush occupying 25% of the body length; and rod-shaped to slightly ellipsoidal extrusomes measuring about 5 x 0.5 microm. S. simplinucleatum is about 110 x 50 microm in vivo, characterized by solid, concave oral bulge, with the impression of doubled oral bulge in right side, macronuclear tortuous strand, usually 30 ciliary rows, 3 anteriorly differentiated to form a dorsal brush, and about 7 microm long rod-shaped extrusomes. S. simplinucleatum is highly variable in body size and length of monokinetidal bristle tail. Dileptus americanus is about 300 x 50 microm in vivo and differs from its congeners by a combination of characters including two macronuclear segments with a single micronucleus in between, two contractile vacuoles in dorsal side of trunk, two size types of rod-shaped extrusomes, a proboscis which occupies about 37% of body length, circular oral opening, and an average of 22 ciliary rows, of which up to 4 are differentiated to form a dorsal brush.  相似文献   

6.
The morphology, infraciliature and silverline system of the marine peritrichous ciliate, Epicarchesium abrae (Precht, 1935) nov. comb., isolated from an abalone-farming pond off the coast of Qingdao, China, are investigated. E. abrae is characterized by: size of zooid in vivo 68 μm×48 μm on average; macronucleus usually J-shaped; one dorsally-located contractile-vacuole; colony regularly dichotomously branched with 4–16 zooids; total number of transverse silverlines 62–72, from peristome to aboral ciliary wreath 41–47, from aboral ciliary wreath to scopula 21–25; outer kinety of peniculus 3 prolonged and converges with peniculus 1.  相似文献   

7.
The leiognathid genus Nuchequula can be defined by the following combination of characters: mouth protruding downward; a narrow band of small, slender, villiform teeth in both jaws; teeth on upper jaw strongly recurved; the lateral line almost complete; a dark blotch on the nape. Although the genus was first established as a subgenus of Eubleekeria, it is here raised to generic level on the basis of the aforementioned morphological characters and recent molecular biological evidence. The genus comprises six valid species: N. blochii (Valenciennes 1835), distributed in India and Thailand; N. flavaxilla sp. nov., occurring only at Panay I., Philippines; N. gerreoides (Bleeker 1851), widely distributed in the Indo-West Pacific, from the Persian Gulf to Cape York, Australia, and north to Taiwan; N. glenysae sp. nov., from northern Australia and Ambon, Indonesia; N. longicornis sp. nov., from the Gulf of Thailand and Indonesia; and N. nuchalis (Temminck and Schlegel 1845), occurring in southern China including Taiwan, and southern Japan. Diagnostic characters of the species belonging to the genus are as follows: N. blochii—breast scaled, cheek naked, and a conspicuous black blotch distally on spinous dorsal fin; N. flavaxilla sp. nov.—breast naked, dorsolateral body surface fully scaled, preorbital spine bicuspid and not expanded distally, and second dorsal and anal fin spines conspicuously elongated; N. gerreoides—breast naked, anterior part of dorsolateral surface of body almost completely scaled, and second dorsal and anal fin spines not conspicuously elongated; N. glenysae sp. nov.—breast completely scaled, cheek scaled, and unique complicated sensory canals present on the suborbital area, extending to the nape; N. longicornis sp. nov.—breast naked, dorsolateral body surface fully scaled, preorbital spine bicuspid or tricuspid and extended distally, and second dorsal fin spines only conspicuously elongated; N. nuchalis—breast naked, anterior part of dorsolateral surface of body widely naked, and a conspicuous dark blotch distally on spinous dorsal fin.  相似文献   

8.
Asteromenia gen. nov. (Rhodymeniales, Rhodophyta) is proposed with a single species, Asteromenia peltata (W. R. Taylor) comb. nov. (basionym: Fauchea peltata W. R. Taylor). Thalli of the proposed new genus are stipitate with dorsiventral, peltate blades that are initially circular in shape but with age become stellate with ligulate arms. Internally, the blades have a polystromatic medulla of large, hyaline cells, grading into a cortex of smaller, pigmented cells. Clusters of translucent cells occur on the dorsal surface of the blade. Tetrasporangia are formed by transformations of intercalary midcortical cells. Mature tetrasporangia have cruciately arranged spores and are densely aggregated in the cortex, mostly on the ventral surface, but occasional tetrasporangia also arise on the dorsal surface. Carpogonial branches are four-celled and arise on inner cortical cells. Auxiliary cells are borne on auxiliary mother cells attached to supporting cells of the carpogonial branches. Cystocarps are protuberant, with well-developed, ostiolate pericarps that often have extended, proboscis-like necks. The new genus differs from the previously described peltate or dorsiventral taxa in the Rhodymeniaceae by its polystromatic medulla (Maripelta and Sciadophycus have a monostromatic medulla), intercalary tetrasporangia formed in an unmodified cortex, and four-celled carpogonial branches (Halichrysis, as typified by H. depressa (J. Agardh) F. Schmitz, has terminal tetrasporangia in nemathecia and three-celled carpogonial branches).  相似文献   

9.
10.
ABSTRACT. Dileptids are haptorid ciliates with a conspicuous proboscis belonging to the oral apparatus and carrying a complex, unique ciliary pattern. We studied development of body shape, ciliary pattern, and nuclear apparatus during and after binary fission of Dileptus terrenus using protargol impregnation. Additional data were obtained from a related species, Pseudomonilicaryon brachyproboscis . Division is homothetogenic and occurs in freely motile condition. The macronucleus is homomeric and condenses to a globular mass in mid-dividers. The proboscis appears in late mid-dividers as a small convexity in the opisthe's dorsal brush area and maturates post-divisionally. The oral and dorsal brush structures develop by three rounds of basal body proliferation. The first round generates minute anarchic fields that will become circumoral kinetofragments, while the second round produces the perioral kinety on the right and the preoral kineties on the dorsal opisthe's side. The dorsal brush is formed later by a third round of basal body production. The formation of various Spathidium -like body shapes and ciliary patterns during ontogenesis and conjugation of Dileptus shows a close relationship between spathidiids and dileptids. On the other hand, the peculiarities of the dileptid morphology and ontogenesis indicate a long, independent evolution.  相似文献   

11.
Microscopic methods were used to investigate the morphological characterization of two novel oligotrich ciliates, Spirostrombidium paraurceolare sp. nov. and Spirostrombidium faurefremieti sp. nov., isolated from a mangrove wetland in Zhanjiang and an intertidal sandy beach in Qingdao, respectively. Spirostrombidium paraurceolare sp. nov. is characterized by three thigmotactic and 8–10 buccal membranelles, the girdle kinety spiralling around cell with one and a half whorls, and located at right anterior third of dorsal side anteriorly. Spirostrombidium faurefremieti sp. nov. can be recognized by a prominently deep and broad buccal cavity, two thigmotactic and 15–19 buccal membranelles, and the girdle kinety spiralling around cell with two whorls. The small subunit ribosomal RNA genes of these two species were sequenced and compared with those of their congeners to reveal nucleotide differences. Phylogenetic analyses revealed that the genus Spirostrombidium is non-monophyletic. Spirostrombidium faurefremieti sp. nov. falls into a clade comprising most congeners, but Spirostrombidium paraurceolare sp. nov. branches off and groups with Varistrombidium kielum with moderate support. A key to the identification of Spirostrombidium species is also provided.www.zoobank.org/urn:lsid:zoobank.org:pub:AB96BEE6-BE3A-4B95-B75A-3469B1C53ABB2  相似文献   

12.
A new species ofChimaera is described from three specimens collected from deep water fishing grounds off the North Island of New Zealand at depths ranging from 327–1020 m. This species is distinguished from all other members of the genus by gray coloration with chocolate brown reticulations and spots covering the body and fins, as well as additional external features such as rounded pelvic fins, first dorsal fin with distinct white margin, preopercular and oral lateral line canals sharing a common branch, and morphology of pelvic claspers in males bifid, the distal 1/3 divided, with pale colored fleshy, distal lobes. Comparisons are made toC. monstrosa andC. owstoni, the two most similar species in the genus. this represents the first species ofChimaera to be described from New Zealand.  相似文献   

13.
A chlorarachniophycean alga, Lotharella amoebiformis, which has been classified in the genus Lotharella is placed into a new genus Amorphochlora gen. nov., based on its phylogenetic position, which has been clarified by the recently accumulated molecular phylogenetic information, and the morphological difference between the vegetative cells of the Lotharella species. Following this taxonomic treatment, a new combination Amorphochlora amoebiformis comb. nov., is proposed.  相似文献   

14.
Scolecostigmina chibaensis on Pinus parviflora is described as a new species. Cercospora cryptomeriicola Sawada on Cryptomeria japonica is transferred to the genus Pseudocercospora, based on the morphological characteristics of the type specimen and newly collected specimens.  相似文献   

15.
Bipolar asymmetry has been considered a morphological characteristic sufficient for differentiation of genera among the Desmidiaceae. Therefore, Micrasterias sudanensis Grönbl., Prowse & Scott, the only species of Micrasterias showing such asymmetry, is made the type of a new genus, Prescottiella, gen. nov.  相似文献   

16.
我们从江苏、浙江两省采到的一些样品中分离得到六株毛霉菌种并鉴定为分别属于三个变种的同一个新种,即单孢共头霉原变种(Syncephalastrum monosporum Zheng et al.sp. nov. var. monosporum),单孢共头霉冠囊变种(Syncephalastrum monosporum Zheng et al. var. cristatum Zheng et al. var. nov.),以及单孢共头霉多重生变种(Syncephalastrum monosporum Zheng et al. var. pluriproliferum Zheng et al. var. nov.).它们与共头霉属的唯一已知种总状共头霉(Syncephalastrum racemosum Cohn ex Schroeter)的主要区别在于全部孢子囊都是单孢的小型孢子囊(柱孢囊)而不是像后者一样孢子成单行排列的多袍柱孢囊.我们把这些菌归人共头霉属而没有为它们专门成立一个新属的理由除因它们与总状共头霉有明显的亲缘关系外,主要还因我们认为在不具备其它重要区别特征的情况下,在毛霉目的分类中,无论在科级或属级的水平上,都不应过分强调单孢孢子囊的作用.尽管单孢共头霉是毛霉目内唯一具单孢子柱孢囊的种,我们仍然把它们归入共头霉属内.至于我们为什么要把这六株菌鉴定为一个种的三个变种而不是三个各自独立的种,则是由于我们承认共头霉属的唯一已知种总状共头霉是一个变异性很大的种而并没有把它分成许多不同的种,因此,我们对这个属的另外一个种,即单孢共头霉同样采用较大的种概念.  相似文献   

17.
We performed a comparative morphological and molecular study on oxytrichid and urostylid stichotrichs (=part of the former hypotrichs). Included are new small subunit (18S) ribosomal RNA (rRNA) gene sequences from five rare oxytrichids (Gonostomum namibiense, Cyrtohymena citrina, Hemiurosoma terricola, Onychodromopsis flexilis, Orthoamphisiella breviseries) and published sequences, based on cultures provided by the senior author, of two key stichotrichid genera, viz., Gastrostyla and Engelmanniella. These and other sequences, altogether 27 species representing 23 genera, were used to analyze how 18S rRNA-based phylogenetic trees can be reconciled with the morphological and ontogenetical data. In 18S rRNA trees, the oligotrichine family Halteriidae invariably clusters within the oxytrichid clade, usually near Oxytricha granulifera, type species of the genus. This position is hardly supported by morphological and ecological evidence and, especially, it contradicts the current ontogenetic findings; possibly, it is an artifact caused by taxa undersampling and/or special molecular evolutionary events. In contrast, most morphological and DNA sequence data of the stichotrichs can be harmonized with the CEUU (Convergent Evolution of Urostylids and Uroleptids) hypothesis which suggests that the urostylid midventral pattern evolved from an oxytrichine ancestor, developing a second time within the Oxytrichidae. The systematic position of one of the two key genera could be clarified with the 18S rRNA sequences: Gastrostyla is a stylonychine oxytrichid. Based on the molecular data and a reassessment of ontogenesis, a new genus, Styxophrya nov. gen., is established for Onychodromus quadricornutus Foissner, Schlegel & Prescott, 1987.  相似文献   

18.
Cyrtophorids are a specialized group of ciliated protozoa with multitudinous morphotypes. In the present work, the morphology and infraciliature of two new and three rarely known species, including two new genera of cyrtophorid ciliates, Heterohartmannula fangi gen. et sp. nov. , Aporthotrochilia pulex (Deroux, 1976) gen. et comb. nov. , Trochilia alveolata sp. nov. , Trochochilodon flavus Deroux, 1976, and Hypocoma acinetarum Collin, 1907, are described. Heterohartmannula gen. nov. is mainly characterized by a combination of features: two circumoral kineties obliquely arranged, podite not surrounded by somatic kineties, and no distinct gap between left and right ciliary field. Aporthotrochilia gen. nov. is diagnosed mainly by: podite present, oral ciliature reduced to two fragments, several kinety fragments positioned on the right posterior of frontoventral kineties and several terminal fragments. Phylogenetic analyses based on the small subunit rRNA (SSU rRNA) gene sequences support the establishment of two new genera and indicate that Heterohartmannula is most closely related to Hartmannula, and Aporthotrochilia is basal to the Cyrtophoria‐Chonotrichia clade. Trochilia alveolata sp. nov. differs from its congeners mainly by having a conspicuous alveolar layer. In addition, detailed live and infraciliature data of Hypocoma acinetarum and Trochochilodon flavus are supplied. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 164 , 1–17.  相似文献   

19.
The morphology and infraciliature of two soil haptorid ciliates, Clavoplites haranti sp. n. and Enchelys terrenum (Foissner, 1984) comb. n., collected from Malé Karpaty Mts. and Biele Karpaty Mts. (Slovakia), were investigated using live observation and protargol impregnation. Clavoplites haranti is distinguished from its congeners by a combination of characters including: theronts spatulate to slenderly fusiform, trophonts bursiform, size about 60 x 25 microm in vivo; massive oral bulge with broadly clavate to lemon-shaped, 1.5-2 microm long extrusomes arranged in a ring in oral bulge; ellipsoidal macronucleus and one globular micronucleus; on average 13 ciliary rows, 3 anteriorly differentiated to an inconspicuous dorsal brush. Enchelys terrenum is about 85 x 30 microm in size and differs from its congeners by a combination of characters including spatulate shape; massive oral bulge with 4-6 microm long, fusiform extrusomes arranged in a ring in oral bulge; ellipsoidal to reniform macronucleus and one globular micronucleus; usually 19 ciliary rows, 3 anteriorly differentiated to an ordinary dorsal brush. The diagnoses of the family Enchelyidae and the genus Enchelys are improved. The new genus Armatoenchelys differs from the genera Enchelys and Apoenchelys in having both body and oral bulge extrusomes. Enchelys geleii, E. longitricha, and E. vermiformis are transferred to the new genus.  相似文献   

20.
Two strains of xylose-containing and Q-10-having ballistoconidiogenous yeasts isolated from plant leaves collected in Taiwan were found to represent two new species of the genus Bullera. In the phylogenetic trees based on the sequence analysis of 18S rDNA and D1/D2 domain of 26S rDNA, these species are located in the Bullera variabilis (Bulleribasidum) cluster in Hymenomycetes. They are described as Bullera begoniae sp. nov. and Bullera setariae sp. nov., respectively.  相似文献   

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