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1.
Recent works on prostomatid ciliates show that some genera of this group have a differentiated oral infraciliature and that their stomatogenesis during division involves the proliferation of only a few somatic kineties. These findings have significant implications regarding the iaxonomic status of these genera and also on the terminology used for the oral structures. In Urotricha ondina , the oral infraciliature consists of (1) a paroral kinety formed of paired kinetosomes that encircle the cytostome at the anterior pole of the cell and (2) 3 adoral organelles, each formed of 2 rows of kinetosomes, ventral in position and obliquely disposed, lying above 3 short somatic kineties that do not reach the anterior pole of the cell. This oral ciliature —formerly known as the corona and brosse, respectively—originate during stomatogenesis from the proliferation of 4 somatic kineties that lie posterior to the adoral organelles of the parental cell.  相似文献   

2.
Two cyrtophorid ciliates, Dysteria yagiui nov. spec. and D. derouxi, were isolated from fish-farming waters at the New Fishing Port of Nagasaki, Japan. Their morphology and infraciliature were investigated using observation of living cells and protargol impregnation. D. yagiui nov. spec. is a large marine species distinguished from its congeners by the presence of 13 ventral kineties in the right field, of which six extend apically and 6–8 short fragments of kineties in the left equatorial field. D. derouxi has the characteristics previously described except that ciliates of this population possess nine ventral kineties in the right field, of which four extend apically.  相似文献   

3.
The morphology and infraciliature of four marine cyrtophorid ciliates isolated from Qingdao, China, were investigated. Based on the present work and on previous data, improved diagnoses for three rarely known species are provided: (1) Mirodysteria decora; small-sized marine Mirodysteria about 35–60 × 25–35 μm in vivo, oval in outline; body surface with two or three conspicuous dorsal spines and one caudal spine; three right kineties, the rightmost one extending dorso-apically; left frontal kineties reduced, each consisting of three basal bodies only; podite subcaudally positioned; two ventrally located contractile vacuoles. (2) Dysteria legumen; body oval with two longitudinal grooves on different plates; six right kineties, the rightmost two of which extend dorso-apically; two left frontal kineties and two ventrally located contractile vacuoles. (3) Dysteria proraefrons; body about 60 × 35 μm in vivo; six right kineties, the two rightmost of which extend dorso-apically and the leftmost one is considerably shortened; three left frontal kineties; two ventrally located contractile vacuoles. A population of D. derouxi with eight or nine right kineties is also briefly described. The current investigation further demonstrates high diversity and cosmopolitan distribution of this highly specialized group of benthic ciliates.  相似文献   

4.
This study investigates the morphology and molecular characteristics of three new cyrtophorid ciliates isolated from China seas: Chlamydodon salinus n. sp., Chlamydodon caudatus n. sp., and Chlamydodon paramnemosyne n. sp. Of these, C. salinus n. sp. differs from its congeners through a combination of body size, a cross‐striated band that is not continuous, the presence of 30–34 somatic kineties, 11–15 nematodesmal rods, and 13 contractile vacuoles. Chlamydodon caudatus n. sp., meanwhile, is characterized by having a conspicuous tail, a continuous cross‐striated band, 34–40 somatic kineties, about 15 contractile vacuoles, and 20–24 nematodesmal rods. Compared with other Chlamydodon species, the third new one, C. paramnemosyne n. sp., could be identified by its continuous cross‐striated band, 16–18 somatic kineties, 5 contractile vacuoles, and 9–12 nematodesmal rods. Based on the sequence of the small subunit (SSU) rRNA gene, the phylogeny of these three new species was analyzed, indicating that they all clustered with other congeners to form a monophyletic assemblage. Based on previous studies and the present work, a brief revision of the genus Chlamydodon is supplied, and a key to aid the identification of Chlamydodon species is given.  相似文献   

5.
Two marine urostylid ciliates, Anteholosticha multicirrata n. sp. and Anteholosticha pulchra (Kahl, 1932) Berger, 2003, were collected from South Korea. These species were identified based on morphology, morphogenesis, and SSU rRNA gene sequence comparison. Anteholosticha multicirrata n. sp. is characterized by the following features: body size 90–125 × 30–45 μm in vivo, shape slender to ellipsoidal in outline, with yellow‐greenish cortical granules distributed along and between dorsal kineties and cirri; single contractile vacuole positioned on left at mid‐body; three frontal, five to seven frontoterminal, one buccal, one to two pretransverse and four to six transverse cirri; three complete dorsal kineties; one left and one right marginal cirral row; about 117 macronuclear nodules; and three to four micronuclei observed during morphogenesis. In addition, based on the observations of morphogenesis, we found that A. pulchra has pretransverse cirri, which were not described in detail in previous studies. Nuclear small subunit ribosomal RNA (SSU rRNA) gene was used to analyse their phylogenetic relationship, and the gene tree supports that the genus Anteholosticha is a highly polyphyletic group.  相似文献   

6.
ABSTRACT. The morphology, infraciliature, and small subunit (SSU) rRNA gene sequences of two new pleurostomatid ciliates, Epiphyllum shenzhenense n. sp. and Loxophyllum spirellum n. sp., isolated from a mangrove wetland near Shenzhen, South China, were investigated. Epiphyllum shenzhenense n. sp. is morphologically characterized by leaf‐shaped cell about 150 × 35 μm in vivo, usually with four contractile vacuoles, 20–29 right kineties and 10–26 left kineties, ca. four macronuclear nodules, and two types of extrusomes (i.e. short spindle‐shaped and long bar‐shaped). As a new species, L. spirellum n. sp. is distinguished from its congeners by its posterior dorsal margin twisted onto the left side, the distribution of extrusomes (evenly arranged along the oral slit, the posterior end, and clustered to 7–13 warts on dorsal margin), the subterminally positioned contractile vacuole, the number of kineties (8–10 on right side, 4–5 on left side), and its genetic distance from congeners. Phylogenetic trees based on the SSU rRNA gene sequence for both organisms were constructed, which indicate that Epiphyllum is a distinct genus and occupies a basal position in the Pleurostomatida clade; L. spirellum n. sp. falls well into the Loxophyllum clade, which has a close relationship with Litonotus and Spiroloxophyllum.  相似文献   

7.
Two new brackish pleurostomatid ciliates, Amphileptus spiculatus sp. n. and A. bellus sp. n. were collected from mangrove wetlands of southern China and their morphology and molecular phylogeny were studied. Amphileptus spiculatus sp. n. can be distinguished from congeners by the presence of 11–14 right and 6–8 left kineties, two macronuclear nodules and a conspicuous beak‐like anterior body end. Amphileptus bellus sp. n. is characterized by the presence of 2–4 macronuclear nodules, 31–35 right and 6 or 7 left kineties and two types of extrusomes. Phylogenetic analyses based on SSU rDNA sequences data indicate that the family Amphileptidae is paraphyletic.  相似文献   

8.
Antarctica is a remote and isolated biotope which makes it an ideal location for studying new and endemic species. Since there is little literature available on the diversity of ciliates in this area, a taxonomic survey of ciliates from melt-water of Collins glacier, King George Island, was carried out from January to March 2006. As a result, the morphology and infraciliature of five ciliates, including one new species, are described using live observations and silver staining: Gastronauta multistriata nov. spec., Neokeronopsis asiatica Foissner et al., 2010, Paraholosticha muscicola Kahl, 1932, Oxytricha sp., and Cyclidium glaucoma Müller, 1786. Gastronauta multistriata nov. spec. is distinguished from its congeners by the following combination of characters: cell size in vivo on average 80 × 40 μm; 5–9 kineties in left ciliary field; 18–23 kineties in right ciliary field, including 10–12 postoral kineties; 7–10 preoral kineties; dorsal brush along anterior dorsal margin, consisting of 5–8 groups of basal bodies. The only minor differences between the current population of N. asiatica and a previously described Antarctic population are the numbers of caudal cirri (6–10 vs. 8–15) and dorsal kineties (11–13 vs. 12–18). Paraholosticha sterkii is synonymised with P. muscicola. The Antarctic population of C. glaucoma corresponds well with a former population from China, the only difference being the number of kinetids in SK n (11–17 vs. 9–11). This work will contribute to the understanding of ciliate diversity in this little studied area.  相似文献   

9.
10.
The morphology and morphogenesis of the kinetofragminophoran soil ciliates, Fuscheria terricola n. sp. and Spathidium muscorum Dragesco & Dragesco-Kerneis, 1979, are described. Stained specimens (protargol) are characterized biometrically. The new species differs from the other species of the genus in its body size, body shape, number of kineties, length of extrusomes, and habitat. Both species have telokinetal stomatogenesis, which commences with a proliferation of kinetosomes at those kineties which bear the brosse. Fuscheria terricola does not have a complex perioral ciliature; indeed, it might be that this species has only monokinetids. Thus only a proliferation of kinetosomes and the separation of the kineties takes place in the prospective division furrow. In contrast, S. muscorum differentiates short dikinetid kinetofragments in the region of the division furrow, which are arranged to form the perioral kinety of the opisthe in the intermediate and late stages of the stomatogenesis. The right part of the perioral kinety develops first. This and other studies show that telokinetal stomatogenesis proceeds very differently depending on the differentiation of the oral ciliature; however, detailed studies on the morphogenesis of kinetofragminophoran ciliates are still too few in number for subtypes to be defined.  相似文献   

11.
Three new cyrtophorian ciliates isolated from coastal areas of China were described based on morphological and genetic data. The Chlamydodon mnemosyne‐like species Chlamydodon similis sp. n. differs from its congeners mainly by its number of somatic kineties. Chlamydodon oligochaetus sp. n. is distinguished from its congeners mainly by having fewer somatic kineties, and/or an elongated body shape. Chlamydodon crassidens sp. n. is characterized mainly by an inverted triangular body shape, a posteriorly interrupted cross‐striated band (5–6 μm wide), and a large cytostome. Moreover, we provided small‐subunit (SSU) rDNA sequences of C. similis sp. n. and C. oligochaetus sp. n. Maximum likelihood (ML) and Bayesian inference (BI) consistently placed C. similis sp. n. as a sister to C. paramnemosyne, but showed different branching position of C. oligochaetus sp. n., which may be due to a low taxon sampling in the Chlamydodontidae and/or an insufficient resolution of the marker gene at species level.  相似文献   

12.
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   

13.
The morphology, ontogenesis, and phylogenetic relationships of a halophile euplotid ciliates, Euplotes qatarensis nov. spec., isolated from the Khor Al‐Adaid Lagoon in Qatar were investigated based on live observation as well as protargol‐ and silver nitrate‐impregnated methods. The new species is characterised by a combination of features: the halophile habitat, a cell size of 50–65 × 33–40 μm, seven dorsal ridges, 10 commonly sized frontoventral cirri, two widely spaced marginal cirri, 10 dorsolateral kineties, and a double silverline pattern. The morphogenesis is similar to that of its congeners: (i) the oral primordium develops hypoapokinetally and the parental oral apparatus is retained; (ii) the frontoventral‐transverse field of five streaks gives rise to the frontal, ventral, and transverse cirri, but not to the cirri I/1 and the marginal cirri; (iii) the dorsal somatic ciliature develops by intrakinetal proliferation of basal bodies in two anlagen per kinety that are just anterior and posterior to the future division furrow; (iv) the caudal cirri are formed by the two rightmost dorsolateral kineties. The SSU rDNA sequence of E. qatarensis branches with full support in the Euplotopsis elegans–Euplotes nobilii–Euplotopsis raikovi clade. The closest related publicly available SSU rDNA sequence is the one of E. nobilii, with which E. qatarensis has 93.4% sequence similarity. Euplotes parawoodruffi Song & Bradbury, 1997 is transferred to the genus Euplotoides based on the absence of frontoventral cirrus VI/3.  相似文献   

14.
15.
The morphologies of two novel ciliates, Arcanisutura chongmingensis n. gen., n. sp. and Naxella paralucida n. sp., collected from Shanghai, China, have been investigated using live observation and silver staining methods. Arcanisutura n. gen. can be easily distinguished from related genera by its inconspicuous, oblique anterior suture. Arcanisutura chongmingensis n. sp. is mainly recognized by its elongated body with a tail‐like posterior end, 25–33 somatic kineties, and 4–11 excretory pores. Naxella paralucida n. sp. can be distinguished from its congeners based on its two short nassulid organelles, fusiform trichocysts, 37–49 somatic kineties, and 16 nematodesmal rods. The small‐subunit (SSU) rRNA gene sequences of these two species are presented, revealing the phylogenetic positions of Arcanisutura and Naxella. Phylogenetic analyses show that Arcanisutura forms a sister clade to other synhymeniid genera, namely, Chilodontopsis, Orthodonella, and Zosterodasys; Naxella is most closely related to Nassula spp. and is located within the monophyletic clade of the family Nassulidae.  相似文献   

16.
The morphology and infraciliature of two pleurostomatid ciliates, Amphileptus gui nov. spec. and A. yuianus nov. spec., collected from mariculture ponds near Qingdao (Tsingtao), China, were investigated using living observations and the protargol impregnation method. These new species are distinguished from their congeners by a combination of characters including their marine habitat and the presence of an apical group of densely packed extrusomes. Amphileptus gui nov. spec. differs from A. yuianus nov. spec. mainly in the number of contractile vacuoles (3–7 vs. 1), the shape of extrusomes (thin bar-like vs. clavate), and the number of left and right somatic kineties (7–11 and 37–50 vs. 4 and 18–22).  相似文献   

17.
During faunistic studies on psammophilic ciliates along the coast of Qingdao, China, a population of the poorly known species Parasonderia vestita (Kahl, 1928) comb. nov. (basionym: Plagiopyla vestita Kahl, 1928) was found and investigated using silver staining methods. These revealed that its oral ciliature is rather unique and composed of polykinetids comprising four parts: prebuccal polykineties, postbuccal polykineties, parabuccal polykineties, and intrabuccal polykineties. Both the pre- and the postbuccal polykineties are, as extensions of the somatic kineties, spiraling and extending from cell surface into buccal cavity. The somatic kineties are composed mainly of dikinetids with some monokinetids and trikinetids inserted. They are separated into two types: four circle kineties and 24–28 bipolar kineties. The circle kineties start from the side of oral region and connect with the opposite section at the end of the body. Phylogenetic analysis based on SSU rRNA gene sequence data indicates that P. vestita falls into the core part of the order Plagiopylida and groups with an environmental sequence with high support and forms a sister clade with Lechriopyla mystax, Plagiopyla frontata and P. nasuta.  相似文献   

18.
Recent studies indicate that there is a high diversity of pleurostomatid ciliates in the coastal waters of China. Here, three new congeners of Loxophyllum, L. caudatum sp. n., L. rugosum sp. n., and L. chinense sp. n., are described following observations of live cells and protargol‐impregnated specimens. All three species usually have two macronuclear nodules and prominent warts along the dorsal margin formed by clustered extrusomes. In addition, L. caudatum sp. n. is characterized by its long conspicuous tail, dot‐like cortical granules, 4 or 5 left and 9 or 10 right kineties, and a single subterminal contractile vacuole. Loxophyllum rugosum sp. n. is distinguished by possessing three prominent ridges on the left side, 7–11 right and 5–7 left kineties. Loxophyllum chinense sp. n. is characterized by having several contractile vacuoles distributed along the ventral margin, 13–18 right and 6–8 left kineties. The small subunit ribosomal DNA (SSU rDNA) sequence similarities among six congeners range from 96.46% to 99.94%. Phylogenetic trees based on the SSU rDNA sequences indicate that all Loxophyllum spp. form a well‐supported monophyletic group. A brief review of the marine and brackish Loxophyllum species is supplied and one new combination, Litonotus multiplicatus (Kahl 1931) comb. n. (basionym Loxophyllum multiplicatum Kahl 1931), and one new name, Litonotus dragescoi nom. n. (basionym L. fasciolatus Dragesco 1966), are suggested.  相似文献   

19.
The morphology and infraciliature of three karyorelictean ciliates, Geleia sinica spec. nov. and two poorly known Kentrophoros species, K. flavus and K. gracilis, isolated from the intertidal zone of a beach at Qingdao, China, were investigated. Geleia sinica spec. nov. is distinguished from its congeners by the following combination of characters: body medium-sized and slender-cylindrical; with a conspicuous prebuccal fossa; 28–34 somatic kineties; about 40 short adoral polykineties; intrabuccal kinety composed of 25–34 dikinetids; paroral kineties composed of closely spaced dikinetids. The comparison with similar congeners clearly supports the validity of this new species based on morphological and small subunit (SSU) rRNA gene sequence data. In light of these new data the “well-known” morphotype, Geleia simplex (Fauré-Fremiet, 1951), is redefined. Two Kentrophoros species are redescribed and improved diagnoses are supplied. Kentrophoros flavus Raikov and Kovaleva, 1968 is mainly characterized by having about 33 macronuclei and 12 micronuclei forming a row that extends along the cell meridian, and 12–19 ciliary rows on the right side of the cell. Kentrophoros gracilis Raikov, 1963 is characterized by having about 14 macronuclei, 13 micronuclei and 10–13 kineties on the right side of the cell.  相似文献   

20.
Two new pleurostomatid ciliates, Loxophyllum lembum sp. n., L. vesiculosum sp. n., and the poorly known L. perihoplophorum Buddenbrock, 1920, isolated from brackish waters in coastal regions of southern China, are described following observations of live cells and protargol‐impregnated specimens. Loxophyllum lembum sp. n. is distinguished by a combination of characters including two macronuclear nodules, 6–9 contractile vacuoles along the ventral margin, 11–14 right and 6–8 left kineties and the presence of cortical granules. Loxophyllum vesiculosum sp. n. differs from its congeners mainly by the unique distribution of contractile vacuoles, several of which lie along the dorsal margin and one on the ventral margin, and 15–21 right and 6–8 left kineties. Loxophyllum perihoplophorum is characterized by its large cell size (350–450 μm long in vivo), 3–5 contractile vacuoles along the dorsal margin in the posterior region of the body, and 19–23 right and 7–9 left kineties. An improved diagnosis of L. perihoplophorum is provided. The SSU rDNA sequence of L. perihoplophorum is reported for the first time and its molecular phylogeny is analyzed. Maximum likelihood and Bayesian inference analyses of SSU rDNA sequence data recover the monophyly both of the order Pleurostomatida and of the genus Loxophyllum.  相似文献   

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