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1.
A terrestrial oxytrichid ciliate Paraparentocirrus sibillinensis n. gen., n. sp., which was found in soil samples of a beech forest stand within the National Park of Sibillini Mountains, Italy, was investigated using live observation and protargol impregnation. The morphology of interphase, morphogenesis, and molecular phylogeny inferred from SSU rDNA sequences of this ciliate were studied. Paraparentocirrus n. gen., is mainly characterized by a semirigid body, an undulating membrane in the Oxytricha pattern, six fronto‐ventral (FV) rows, the absence of transverse cirri, one right and one left row of marginal cirri, four dorsal kineties, two dorsomarginal rows, and caudal cirri at the end of dorsal kinety 4. During morphogenesis, oral primordia develop through the proliferation of basal bodies from some cirri of FV rows 4 and 5, and FV row 6 takes part in the anlagen formation of the proter. The dorsal morphogenesis was typical of oxytrichids, with simple fragmentation of dorsal kinety 3, and the dorsomarginal rows developed from the right marginal row. Phylogenetic analyses based on the SSU rDNA sequences support the classification of this new genus in the stylonychines.  相似文献   

2.
A soil hypotrich ciliate, Afrokahliella paramacrostoma n. sp., was discovered in China. Its morphology, morphogenesis and molecular phylogeny were investigated using standard methods. The new species is characterized as follows: body about 140–180 × 60–70 μm in vivo, cortical granules absent, contractile vacuole positioned about 40% down length of body, 5–9 macronuclear nodules, 34–49 adoral membranelles, 3–5 buccal and 3–6 parabuccal cirri, usually two frontoventral rows, three or four left and two or three right marginal rows, three dorsal kineties and one dorsomarginal kinety; 1–3 and one or two caudal cirri located at the ends of dorsal kineties 1 and 2, respectively. The ontogenetic process is characterized by: (1) the marginal anlagen on each side develop in the outer right and the inner left marginal rows, respectively; (2) five frontoventral-transverse cirral anlagen, anlagen II–IV develop in secondary mode; (3) dorsal morphogenesis follows a typical Urosomoida-pattern, no parental dorsal kineties are retained; (4) caudal cirri are generated at the ends of dorsal kineties 1 and 2. Phylogenetic analyses based on SSU rDNA sequence data reveals that Afrokahliella paramacrostoma n. sp. is closely related to Parakahliella macrostoma and Hemiurosomoida longa.  相似文献   

3.
Paraurosomoida indiensis gen. nov., sp. nov. was isolated from a soil sample collected from Kyongnosla Alpine Sanctuary in the Eastern Himalayas. The present study reports the morphology, morphogenesis, and molecular phylogeny inferred from 18S rDNA sequence. The study is based on live and protargol-impregnated specimens. Paraurosomoida indiensis is very flexible, measures about 90 × 25 μm in life and possesses citrine cortical granules randomly distributed singly and in small linear groups. Paraurosomoida indiensis has undulating membranes nearly in Oxytricha pattern; only 11 frontal-ventral cirri due to lack of all pretransverse ventral and transverse cirri; one dorsomarginal row and three bipolar dorsal kineties. Divisional morphogenesis resembles oxytrichids involving six parental cirri in primordia formation. Anlagen V and VI for both proter and opisthe are formed from two primary primordia originating from disaggregated cirri V/4 and V/3 respectively. Three dorsal kineties develop from within row anlagen without a kinety 3 fragmentation. Molecular analyses consistently place P. indiensis with soft bodied oxytrichids.  相似文献   

4.
The morphology, morphogenesis and molecular phylogeny of the oxytrichid ciliate, Monomicrocaryon euglenivorum euglenivorum (Kahl, 1932) Foissner, 2016, isolated from freshwater in a seaside park, Guangzhou, China, were investigated. Monomicrocaryon euglenivorum euglenivorum can be recognized as follows: caudal cirri in midline of body; dorsal kinety 1 without a one-kinetid-wide gap; transverse cirri acicular or rod-shaped with a fringed distal end; right marginal row commences at level of buccal vertex or anterior to buccal vertex. The main events during binary fission are as follows: (1) the proter retains the parental adoral zone of membranelles entirely; (2) frontoventral-transverse cirral anlagen I–VI are segmented in the ordinary pattern 1:3:3:3:4:4 from left to right, which form three frontal, four frontoventral, one buccal, three postoral ventral, two pretransverse ventral and five transverse cirri, respectively; (3) dorsal morphogenesis is in the typical Oxytricha-pattern, but fragmentation of dorsal kinety 3 is indistinct; and (4) three caudal cirri are formed, one at the posterior end of each of dorsal kineties 1, 2 and 4. Phylogenetic analyses based on SSU rDNA sequences showed that M. euglenivorum euglenivorum clustered with Kleinstyla dorsicirrata and Heterourosomoida lanceolata rather than with its congener M. elegans. The genus Monomicrocaryon is not monophyletic in this study; however, its monophyly is not rejected by the AU test.  相似文献   

5.
Oxytricha granulifera sp.n. differs from other members of the genus by its subpellicular granules and the strongly shortened dorsal kinety 4. The overall pattern of the morphogenetic events is similar to that known from other Oxytrichidae. However, the oral primordium evolves de novo between the left marginal cirral row and the postoral cirri. The six anlagen of the frontoventral cirri are of different origin. Two anlagen of the proter evolve from parental frontal cirri, two from the opisthe, and one includes basal bodies of the proter and opisthe. Two anlagen of the opisthe evolve from the oral primordium, and three primordia originate from the postoral cirri. Frontal cirrus 1 evolves from the paroral membrane in the proter, and from the oral primordium and the anlagen of the frontoventral cirri in the opisthe. The genus Oxytricha can be subdivided into several groups with regard to the origin of its oral primordium and the development of the frontoventral cirri. The morphogenesis of the dorsal kineties in the Hypotrichida is reviewed. Seven different modes of origin are distinguished. We conclude that morphogenetic features cannot be used in the classification of the Hypotrichida at the generic level, because we have too little information to decide whether special morphogenetic features are important at the generic or species level.  相似文献   

6.
The morphology and morphogenesis of a new ciliate, Heterokeronopsis pulchra g. n., sp. n., isolated from a mangrove wetland near Shenzhen, southern China, were investigated using live observation and protargol impregnation methods. Heterokeronopsis g. n. is characterized by having a bipartite adoral zone, an extremely shortened paroral membrane, frontal cirri arranged in an indistinct bicorona, a midventral complex composed of midventral pairs and midventral row(s), one left and one right marginal row, bipolar dorsal kineties, and buccal cirri; frontoterminal, transverse, and caudal cirri are absent. The single species H. pulchra sp. n. has a long, slender body that is brownish in colour, two kinds of cortical granules, one posteriorly located contractile vacuole, one buccal cirrus, usually six frontal cirri, three dorsal kineties, and one midventral row. The main morphogenetic features are: (i) the old oral apparatus is completely replaced by new structures derived from the oral primordium of the proter which originates de novo on the dorsal wall of the buccal cavity, (ii) the posteriormost frontal-midventral-transverse cirral anlage generates a midventral row, (iii) no frontoterminal and transverse cirri are formed, (iv) the anlagen for the marginal rows and the dorsal kineties are formed intrakinetally, and (v) the macronuclear nodules fuse into a mass at the middle stage. Phylogenetic analyses based on SSU rRNA gene sequence data reveal that Heterokeronopsis pulchra is a member of the family Pseudokeronopsidae and is most closely related to Nothoholosticha fasciola.  相似文献   

7.
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   

8.
The morphology and morphogenesis of Diophrys japonica spec. nov., isolated from the Mie Port, Nagasaki, Japan, were investigated from life and following impregnation with protargol. The new species is recognized by the following characters: Body elliptical in outline and slightly greyish to yellowish in color; size in vivo about 80-120 x 50-70 microm; pellicle flexible, with underlying granules densely arranged in lines; ciliature comprising about 30-46 adoral membranelles, 4-7 frontal, 1-4 ventral and 4-7 transverse cirri, always 1 left marginal and 3 caudal cirri, and 4 dorsal kineties; usually two macronuclear nodules; fragment kinety with 2-5 dikinetids; marine habitat. The main morphogenetic events are: (1) the opisthe's oral primordium develops de novo in a subsurface pouch near the left transverse cirri; (2) the proter retains the parental AZM except for reorganization of some proximal membranelles; (3) cirral anlagen for the frontal, ventral and transverse cirri in both dividers develop separately from the oral primordium or parental cirri, and are derived from the separation of primary primordia that originate de novo; (4) the anlagen for the left marginal cirrus and fragment kinety also form de novo and separately; (5) dorsal kinety anlagen occur within the parental structures at mid-body and posterior end of the cell, of which the right-most one contributes three caudal cirri from its posterior portion. Based on available ontogenetic data, the author proposes that the numbers of left marginal and caudal cirri can be regarded as reliable characters for species identification, while the numbers of frontal, ventral and transverse cirri are not consistent enough for species distinction. A key to the eleven adequately known species of Diophrys is presented.  相似文献   

9.
A new soil ciliate, Pseudonotohymena antarctica n. g., n. sp., from King George Island, Antarctica, is described based on live observation, protargol impregnation, and its 18S rRNA gene. The new genus Pseudonotohymena is morphologically similar to the genus Notohymena Blatterer and Foissner 1988 in the following characteristics: 18 fronto‐ventral‐transverse cirri, a flexible body, undulating membranes, dorsomarginal kineties, and the number of cirri in the marginal rows. However, Pseudonotohymena differs from Notohymena particularly in the dorsal ciliature, that is, in possessing a nonfragmented dorsal kinety (vs. fragmented). In addition, the molecular phylogenetic relationship of the new species differs from that of Notohymena species. On the basis of the morphological features, the genetic data, and morphogenesis, we establish P. antarctica n. g., n. sp. In addition, the cyst morphology of this species is described.  相似文献   

10.
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   

11.
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   

12.
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   

13.
宋微波 《动物学报》1997,43(1):90-95
钩刺斜管虫口和体纤毛器演化模式是研究该类动物个体发生的优秀模型。通过跟踪研究,澄清了后仔虫口器发生以及体纤毛器起源上的几点疑问,并证实:体左侧二列片段动基列为同源再造而非来自老结构的分裂或复制;三列围口纤毛均为双动基列构造;后仔虫口原基场的构建系由5列体动基列共同参与完成的,其中最左侧两列短的原基片段与原基1整合为一体,从而发展成营养期虫体的外围口动基列;后仔虫背触毛原基为独立发生。  相似文献   

14.
15.
We discovered a new brackish water oxytrichid Pseudocyrtohymena koreana n. g., n. sp. in South Korea and investigated the new species on the basis of morphology, ontogenesis, and 18S rRNA gene sequences. The new genus has the 18 frontal‐ventral‐transverse cirri of typical oxytrichids with flexible body, cortical granules, Cyrtohymena undulating membranes (UM), and one left and one right marginal cirral row. Ontogenesis of the new species indicated that dorsal kinety anlage 3 stretches within the parental row without any fragmentations (Urosomoida pattern) and exclusively forms all caudal cirri. The new genus is morphologically similar to Cyrtohymena Foissner, 1989, but has the following distinctive features: (i) caudal cirri absent in dorsal kineties 1 and 2 (vs. present in Cyrtohymena); and (ii) dorsal kinety 3 nonfragmented (vs. fragmented in Cyrtohymena). Further, we collected an additional species Neokeronopsis asiatica Foissner et al. 2010, from King George Island, Antarctica, and the species shares the morphology of UM with Cyrtohymena. Herein, we describe the previously unidentified characteristics of N. asiatica (i.e., cortical granules, body flexibility, contractile vacuole, and 18S rRNA gene sequence). In addition, we obtained two 18S rRNA gene sequences from Cyrtohymena muscorum and Parasterkiella thompsoni to expand samples for phylogenetic analysis. Our 18S rRNA gene tree supports the hypothesis that the Cyrtohymena UM pattern might have evolved several times in hypotrichs (e.g., Neokeronopsidae, Oxytrichinae, and Stylonychinae).  相似文献   

16.
通过活体观察和蛋白银染色法对采自青岛沙滩半咸水的变藓棘毛虫Sterkiella histriomuscorum(纤毛门, 腹毛目)进行了形态学及细胞发生学研究。该种群形态学与前人报道的土壤及淡水种群基本一致: 虫体近长椭圆形, 活体大小约(100-160) m (40-75) m; 无皮层颗粒; 2938片口小膜; 额棘毛3根; 额腹棘毛4根; 口后腹棘毛3根; 横前腹棘毛2根; 横棘毛3-5根; 左右缘棘毛列分别由17-23、20-24根棘毛组成; 6列背触毛; 2枚大核。其主要发生学特征如下: (1)老口围带完全保留, 老波动膜解体重建; 后仔虫口原基独立发生; (2)额腹横棘毛为5原基次级发生式, 部分原基来自老棘毛解体, 以2:3:3:4:4方式分化为新棘毛; (3)缘棘毛原基产生于老结构中, 并向两极延伸逐渐形成前后仔虫的新结构; (4)背触毛发生为典型Oxytricha模式; (5)大核在发生过程中完全融合。研究对首次在半咸水生境中发现的变藓棘毛虫种群进行了活体形态学和纤毛图式描述, 补充了显微照片、性状统计数据及发生过程的细节信息。    相似文献   

17.
The morphology and ontogenesis of two new hypotrich ciliates, Hemiholosticha solitaria and Hemiholosticha germanica, were studied using live observation, protargol impregnation, and scanning electron microscopy. Both species share a medium-sized, almost globular body with a short anterior projection; two macronuclear nodules with a single micronucleus in between; a central contractile vacuole; three or four ventral, one postoral, one right and one left marginal cirral row; and three dorsal kineties extending along ribs. However, H. germanica is distinguished from congeners by a higher number of cirri in ventral rows R1 and R2 (3–6 vs. 2 cirri in each row). Hemiholosticha solitaria differs from congeners by having four (vs. three) ventral cirral rows and by the lack (vs. presence) of intracellular green algae. The ontogenesis of H. solitaria follows the H. pantanalensis mode in that (i) the oral primordium develops in a deep pouch and generates the first two cirral streaks in addition to adoral membranelles and undulating membranes, (ii) the undulating membrane anlage does not produce any cirri, and (iii) the longitudinal ventral cirral row R3 originates from two anlagen. The ontogenetic peculiarities along with the 18S rRNA gene phylogenies suggest classification of Hemiholosticha, Psilotrichides, and Urospinula into a new family, Hemiholostichidae.  相似文献   

18.
19.
The present work describes the morphology and infraciliature of a new hypotrichous ciliate, Clapsiella magnifica gen. n., sp. n., found in rewetted soil from a temporal pond in Argentina. It was studied by means of live observation and protargol impregnation. Its main diagnostic features are: Flexible hypotrich measuring 250–320 μm × 70–140 μm in vivo; two macronuclear nodules and 4–6 micronuclei. Single contractile vacuole. Cytoplasm transparent, cortical granules absent. Somatic ciliature composed of a tricorona of cirri, three buccal(?) cirri, 6–9 ventral rows, 3–5 right marginal(?) rows, one left marginal row, and 12–17 transverse cirri. Dorsal pattern rather complicated, with about 14 kineties and kinety fragments, with scattered kinetids among them; 17–28 caudal cirri arranged in three rows on dorsal kineties 1, 3, and 7. Remarkably, dorsal kinetids have two or four basal bodies, bearing a stiff bristle arising from left anterior basal body. Adoral zone composed of 70–92 membranelles, occupying about 40% of body length in protargol preparations; paroral and endoral curved, resembling a cyrtohymenid pattern. The peculiar dorsal ciliary arrangement and the unique combination of other characters require the establishment of a new genus for this new species, which is considered incertae sedis in the Hypotricha but possibly related to the oxytrichids.  相似文献   

20.
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   

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