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1.
ABSTRACT. Trachelolophos gigas n. g., n. sp. and T. filum (Dragesco & Dragesco-Kernéis, 1986) n. comb. (basionym: Tracheloraphis filum) were discovered in the mesopsammon of the French Atlantic coast at Roscoff. Their morphology and infraciliature were studied in live and protargol impregnated specimens. The new genus, Trachelolophos, belongs to the family Trachelocercidae and is unique in having a conspicuous ciliary tuft, which is very likely a highly modified brosse, in the oral cavity. The two species investigated have a very similar infraciliature, differing only in morphometric characteristics and in the nuclear configuration. The entire somatic and oral infraciliature consists of dikinetids which have both basal bodies ciliated or only the anterior or posterior ones, depending on the region of the cell. The right side is densely and uniformly ciliated. Its kineties extend onto the left side to the glabrous stripe, where an anterior and posterior secant system are formed, reducing the number of kineties in the narrowed neck and tail region. The left side bears a narrow glabrous stripe bordered by slightly irregularly arranged dikinetids having rather stiff cilia (bristles), possibly forming an uninterrupted, prolate ellipsoidal (bristle) kinety as indicated by their ciliation. The bristle kinety commences subapically at the right margin of the glabrous stripe, extends posteriorly, then anteriorly at the left, to end up at the right margin again. The dikinetids of the right posterior portion of the bristle kinety have the posterior basal bodies ciliated, whereas the anterior basal bodies are ciliated in its left and right anterior portion. The ends of the bristle kinety meet distinctly subapically at the right margin of the glabrous stripe, as indicated by the diametrically opposed ciliation of the dikinetids. The anterior region (head) of the cell bears a distinct circumoral kinety composed of very regularly arranged dikinetids, associated with nematodesmata forming an oral basket together with the nematodesmal bundles originating from the oralized somatic dikinetids at the anterior end of the somatic kineties. The systematics of trachelocercid ciliates are briefly reviewed and discussed.  相似文献   

2.
The morphology and phylogeny of Pleuronema binucleatum n. sp., P. parawiackowskii n. sp., and P. marinum Dujardin 1841, collected from Hangzhou Bay estuary, China, were investigated using standard methods. Pleuronema binucleatum n. sp. can be identified by possessing about 90–120 × 35–50 μm cell size in vivo, reniform body outline, two macronuclei, six to eight preoral kineties, 32–41 somatic kineties, and posterior end of the anterior fragment of membranelle 2 (M2a) hook‐like. Pleuronema parawiackowskii n. sp. is characterized by the combination of the following characters: body size about 60–90 × 20–40 μm in vivo, elliptical in outline, four to eight preoral kineties, 20–29 somatic kineties, posterior portion of the M2a slightly curved but nonhooked, and single macronucleus sausage‐like. After comparison with other populations of P. marinum, it is suggested that many misidentifications exist in previous studies. And an improved diagnosis of P. marinum was supplied: cell about 95–180 μm long, elliptical in outline; 2–4 preoral kineties and 53–70 somatic kineties; both membranelle 1 and membranelle 3 three‐rowed; posterior end of the M2a straight; single contractile vacuole characteristically positioned near mid‐body. The small subunit rRNA genes of three forms were sequenced. Phylogenetic analyses indicate that the monophyly of the genus Pleuronema is still not supported.  相似文献   

3.
4.
The morphology and infraciliature of two new marine cyrtophorid ciliates, Paracyrtophoron tropicum nov. gen., nov. spec. and Aegyria rostellum nov. spec., isolated from tropical waters in southern China, were investigated using live observation and protargol impregnation methods. Paracyrtophoron nov. gen. differs from the closely related Cyrtophoron by lack of fragment kinety at anterior ends of right somatic kineties and thigmotactic cilia in posterior portion of ventral surface, while from the well-defined Chlamydodon by lack of the cross-striped band around the periphery of the somatic field. Paracyrtophoron tropicum nov. spec., the type of the new genus, can be recognized by the combination of the following characters: cell size about 150-175×70-90μm in vivo; elliptical to kidney-shaped in outline, dorsoventrally flattened about 2.5:1; conspicuous cortical granules; one canal-like depression extending from postoral area to subcaudal region of cell; ca. 90 somatic kineties; 12-16 nematodesmal rods; one or two terminal fragments on dorsal side. Aegyria rostellum is characterized by the following features: size about 90-150×40-70μm in vivo, triangular or ear-shaped body with broad anterior end, having a rostriform structure and pigment spots, 56-63 somatic kineties, one preoral kinety, three or four circumoral kineties, and 32-42 nematodesmal rods. Based on previous and current studies, the definition for the genus Aegyria is updated: body dorsoventrally flattened; oral ciliature consisting of one preoral and several circumoral kineties; podite located in posterior ventral region and surrounded by somatic kineties; no obvious gap between right and left somatic kineties; postoral and left somatic kineties progressively shortened posteriorly from right to left. Additionally, two new combinations were proposed.  相似文献   

5.
A philasterine scuticociiiate 82-133 μm in length and 29-51 μm in width is described from the intestine of the solitary tunicate Ascidia ceratodes. It has 44 somatic kineties, an anterior dorsal bald spot, and a triangular scutico-vestige which lies above recessed posterior oral polykinetids.  相似文献   

6.
The morphology and morphogenesis of a marine ciliate, Epiclintes auricularis rarisetus nov. sspec., collected from Qingdao, northern China were studied on live and protargol-impregnated specimens. This isolate can be recognized by its elongate, contractile and tripartite body with a size of 200-400×20-40 μm in vivo, about 30 ventrally located adoral membranelles, short undulating membranes, 2-3 frontal and 10-18 transverse cirri as well as 8-9 fronto-midventral rows, 22-31 left and 35-54 right marginal cirri, but no caudal cirri, invariably 3 dorsal kineties, of which kineties 1 and 3 link together anteriorly, 24-70 macronuclear nodules, marine habitat, and contribution of almost all frontal-midventral transverse cirral anlagen (FVT anlagen) to the formation of fronto-midventral rows. In its divisional morphogenesis, this species demonstrates some features rarely if ever found in any other urostyloids, e.g. partial replacement of the old adoral zone of membranelles, de novo formation of the oral primordium and the anlagen for marginal rows and dorsal kineties, contribution of almost all FVT anlagen to the transverse cirri, lack of frontoterminal cirri. In addition, its morphogenesis appears to differ in detail from that of E. auricularis auricularis nov. stat., based on published data. These remarkable morphogenetic traits of Epiclintes suggests a questionable systematic position for this genus in the Urostyloidea, therefore, further researches are urgently needed.  相似文献   

7.
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   

8.
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   

9.
Hu  Xiaozhong  Song  Weibo 《Hydrobiologia》2001,448(1-3):171-179
The morphology and morphogenesis of the marine hypotrichous ciliate Holosticha heterofoissneri nov. spec. from mollusc culture in Qingdao, China are described based on living and protargol-impregnated specimens. The new species is characterized by: adoral zone slightly bipartite, consisting of on average 43 membranelles; constantly 5 dorsal kineties, and 12 pairs of cirri in midventral rows, and 14–16 macronuclear segments, which differs from the closely related species, H. foissneri. Its morphogenetic process shows the following features: (1) the parental AZM is retained unchanged and will be inherited by the proter, only the old UM reorganized; (2) FVT-cirral anlagen in both division parts derive from the breaking of primary primordia; (3) during the formation of FVT-cirral anlagen, most midventral cirri remain intact; and there appears an 'extra' anlage (EA) between the UMA and other FVT-cirral primordia; (4) the generation type of the dorsal kineties is of 'one group mode', the leftmost one of the 4 primordia fragmentates to form a new kinety; (5) at the early stage of morphogenesis, replication bands of macronuclear segments are apparently present.  相似文献   

10.
Magnolia denudata var. glabrata Y. L. Wang et S. Z. Zhang var. nov. is described and illustrated from Hunan, China. The variety occurs mainly in semi‐evergreen forest of south Hunan at altitudes between 700 and 1260 m a.s.l. It differs from M. denudata var. denudata by its green and glabrous twigs and leaves which are glabrous above and have some white pubescence underneath. With its white flowers consisting of mostly 9 tepals, it differs from M. sprengeri Pamp. which mainly has 12 tepals in various shades of red/pink to white. The new variety is rare and considered endangered due to habitat destruction.  相似文献   

11.
研究对采自青岛沿海的两种海洋纤毛虫-盾圆双眉虫与伪寡毛双眉虫做了形态学重描述。盾圆双眉虫与前人所报道的种群具有十分相似的纤毛图式,但在额-腹棘毛分布、大核片段、小膜及背触毛数目等方面表现出细微的变异性。此外,该青岛种群个体较小。统计学比较还表明,迄今缺乏研究的一海洋种,泥生双眉虫极可能为盾圆双眉虫(Diophrys scutum)的同物异名。伪寡毛双眉虫(Diophrys apoligothrix)为一新近报道的罕见种,研究基于新采集种群对其进行了补充性观察和描述。    相似文献   

12.
ABSTRACT. Specimens of the rare ciliate Discomorphella pectinata (Levander, 1894) Corliss, 1960 were impregnated with silver nitrate in 1963. The body is discoid, about 60 μ m long, laterally compressed and adorned with long spines. The somatic kineties on the right and left sides are sparse, sometimes disorganized, and locally without cilia. The oral zone has a complex infraciliature that lies above two series of ventral kineties and below a large, visor-like, epistomial fringe. The arrangement of this fringe is similar to that observed in some other heterotichous ciliates, notably members of the Metopidae and Caenomorphidae.  相似文献   

13.
14.
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   

15.
The living morphology, infraciliature and morphogenesis of a new marine cyrtophorid ciliate, Hartmannula sinica nov. spec., collected from Qingdao, north China, have been investigated. The new species is characterized by: size in vivo 90–130×40–50 μm, body long elliptical in outline, cilium-free field covered with a conspicuous alveolar layer; 24–31 ventral kineties, the rightmost 6–9 of which extend apically; 20–24 nematodesmal rods; about 15 sparsely distributed contractile vacuoles; a yellowish pigment spot is always present near the anterior tip of the cell. Morphogenetic events exhibit a pattern, which is homologous with that of related cyrtophorids. The main features are as follows: (1) preoral and circumoral kineties of opisthe develop from the oral primordium that forms in mid-body from sections of 3 postoral kineties, while parental preoral and circumoral kineties are retained; (2) parental cytostome and nematodesmal rods are resorbed in middle divisional stages and then replaced by newly formed structures; (3) the heteromerous macronucleus unifies in the late divisional stage.  相似文献   

16.
The principal characteristics of stomatogenesis during division in Climacostomum virens are: (A) Kinetosomal proliferation on the left side of a variable number of kineties in the ventral somatic cortex forms an oral primordium consisting of several kinetosomal fields, which then fuse to form a single anarchic field. (B) A constant topographical relationship exists between the primordium and a well defined cortical pattern, the zone of discontinuity. (C) The anarchic field primordium divides into 2 unequal parts—to the left, the AZM primordium, and to the right, the paroral primordium, which differentiates into the apical membranelles, the peristomial field, and the buccal tube. (D) Preoral and oblique kineties of the somatic cortex form along the right side of the paroral primordium. (E) Parental oral structures are partially dedifferentiated. Stomatogenesis in C. virens and other heterotrichs is compared.  相似文献   

17.
A new hypotrichous ciliate, Apoterritricha lutea n. g., n. sp., was discovered in a sample of a terrestrial liverwort from Korea. Its morphology was studied using detailed in vivo observation and protargol impregnation. Its phylogenetic relationships were revealed by analyses of the 18S rRNA gene. This new taxon is characterized by a combination of the following traits: (i) ellipsoidal to narrowly ellipsoidal body with an average size of 230 × 85 μm; (ii) two macronuclear nodules and two to five micronuclei; (iii) golden yellow cortical granules, forming small groups along the microtubular appendages of cirri, adoral membranelles, and dorsal kineties; (iv) typically three frontal cirri, one buccal cirrus, four frontoventral cirri, seven midventral cirri, two pretransverse cirri, seven transverse cirri, ca. 38 left, and ca. 36 right marginal cirri; and (v) on average six dorsal kineties, three dorsomarginal kineties, and three caudal cirri. In molecular phylogenies, A. lutea clusters with strong support within a clade containing Afrokeronopsis aurea and several “typical” oxytrichids having golden yellow to brown cortical granules. In this light we propose a hypothesis that is not unambiguously rejected by the present phylogenetic analyses, which shows how the Afrokeronopsis‐like pattern could have evolved from a Rubrioxytricha‐like ancestor via an Apoterritricha‐like stage by cirri‐multiplication.  相似文献   

18.
The morphology of living cells and the infraciliature of a new marine cyrtophorid ciliate, Dysteria derouxi nov. spec., collected from the coastal area of Qingdao, China, have been investigated. This species is characterized by: size about 100×40 μm in vivo, body rectangular in outline; 8 ventral kineties in the right field, of which the right-most 3 extend dorso-apically; 6–9 short kineties in the left equatorial field; two ventral contractile vacuoles; and marine habitat. Based on the data of morphology and infraciliature, an updated key to 12 Dysteria species is supplied.  相似文献   

19.
The morphology and morphogenesis of a new ciliate species, Neobakuella aenigmatica n. sp., which was discovered in an estuary in Korea, were investigated, using live observation, protargol impregnation, and scanning electron microscopy. This new species is characterized by a large (185–300 × 55–105 μm in vivo), elongate‐ellipsoidal, flexible but not contractile body. It has ellipsoidal, yellowish cortical granules, 1.3 × 1.0 μm in size. The species has invariably 3 frontal and 2 frontoterminal cirri, about 5–10 buccal and 1–6 parabuccal cirri, 7 midventral rows, and 1 right and 2–4 left marginal rows. The outer left marginal row(s) consists of 1–7 short rows of cirri. The nuclear apparatus comprises 130 macronuclear nodules and 2 spherical micronuclei on average. The dorsal ciliature consists of 3 dorsal kineties. The leftmost left marginal row(s) likely develops from anlagen originating from both the rightmost and leftmost left marginal row(s). The molecular phylogenetic tree based on SSU rDNA suggests the nonmonophyly of the genus Neobakuella.  相似文献   

20.
Two new urostylid species, Holostichides heterotypicus n. sp. and Holosticha muuiensis n. sp., were discovered in South Korea. Morphological and phylogenetic analyses were carried out to confirm that these species are new to science. Holostichides heterotypicus is mainly characterized by the following combination of features: 110–205 μm long in vivo; 5–10 frontoterminal cirri; 6–8 midventral pairs with 2–3 midventral cirral rows; cortical granules present; four bipolar dorsal kineties; and 6–9 caudal cirri. Ontogenetic features of H. heterotypicus are similar to those of H. typicus. Phylogenetic analyses revealed that Hheterotypicus was distantly separated from bakuellid genera Apobakuella, Bakuella, Metaurostylopsis, and Neobakuella. This result is supported by the following features: transverse cirri (present in the other four bakuellids vs. absent in Holostichides) and caudal cirri (absent in the other four bakuellids vs. present in Holostichides). Holosticha muuiensis n. sp. is mainly distinguished from its congeners by the following combination of features: 100–185 long in vivo; shortened undulating membrane; cortical granules lacking; contractile vacuole absent; 51–66 adoral zone of membranelles; 42–60 macronuclear nodules; and five bipolar dorsal kineties. In the phylogenetic tree, Holosticha muuiensis n. sp. clustered with a Holosticha group (containing Holosticha diademata, Holosticha foissneri, and Holosticha heterofoissneri).  相似文献   

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