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1.
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   

2.
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   

3.
A new hypotrichous ciliate, Oxytricha seokmoensis sp. nov., was discovered in a soil from a forest in South Korea and described based on the observations of living and stained specimens. In addition, phylogenetic analyses were performed using the small subunit ribosomal RNA (18S rRNA) gene sequence. Morphologically, the new species is similar to the O. granulifera-complex in terms of ciliary structure and arrangement of cortical granules, but dorsal kineties 3 and 4 (not completely separated vs. separated) and macronuclear nodules in the cyst (separated vs. fused) differ. Oxytricha seokmoensis is most similar to O. pulvillus, but can be distinguished by the number of adoral membranelles (30–40 vs. 23–27), contractile vacuole (present vs. absent), number of left (27–37 vs. 17–25) and right (27–35 vs. 18–23) marginal cirri, and lepidosomes on the cyst surface (present vs. absent). In a phylogenetic tree, O. seokmoensis is distinctly separated from the O. granulifera clade, but is sister to the Paroxytricha clade. In addition, O. seokmoensis and P. longigranulosa have the smallest genetic difference (d = 0.015, 23 of 1579 nt difference). This close relationship is supported by incomplete dorsal kinety 3 fragmentation and separated macronuclear nodules in resting cysts.  相似文献   

4.
The live morphology, infraciliature and morphogenesis of a new urostylid ciliate, Trichototaxis marina n. sp., collected from coastal water in Qingdao, China, were studied based on the observations of live and silver stained specimens. The new species is characterised as follows: body very flexible and contractile, slight to brick-reddish in colour due to irregularly-shaped, brick-red pigments; ca. 70 adoral membranelles; about 17 frontal cirri arranged in a bicorona; average 67 midventral pairs, the right base of each pair being conspicuously larger than the left base; five to seven transverse cirri; constantly two frontoterminal, one buccal and two pretransverse ventral cirri; two or three left marginal rows; right and innermost left marginal rows with 56–92 and 66–106 cirri, respectively; six bipolar dorsal kineties; more than 100 macronuclear nodules. The characteristic morphogenetic feature in T. marina is the development of the left marginal rows, that is, only one left marginal row is newly built the other one or two being retained from the parental cell. Phylogenetic analyses based on small subunit ribosomal gene sequence data reveal a close relationship of T. marina with members of family Pseudokeronopsidae.  相似文献   

5.
The morphology, morphogenesis and molecular phylogeny of a new saline soil hypotrich ciliate, Uroleptoides salina nov. spec., discovered from China, was investigated. The new species is characterized as follows: body 150–215 × 40–50 μm in vivo, slender and highly flexible; usually four ellipsoidal macronuclear nodules; contractile vacuole absent; cortical granules absent; endosymbiotic algae present; amphisiellid median cirral row consists of 14–25 cirri and terminates about 47% down length of body; usually three buccal cirri and 3–13 cirri left of anterior portion of amphisiellid median cirral row; 3–5 transverse cirri. Morphogenesis during binary fission is characterized by: (1) the parental adoral zone of membranelles is retained completely, parental paroral contributes to the formation of the undulating membranes anlage for the proter; (2) the oral primordium of the opisthe is formed apokinetally; and (3) the amphisiellid median cirral row is formed from two anlagen. Phylogenetic analyses based on SSU rDNA sequence data show that Uroleptoides salina nov. spec. has a close relationship with its morphologically similar species, U. longiseries, U. magnigranulosus, Orthamphisiella breviseries, and Parabistichella variabilis.  相似文献   

6.
The morphology and morphogenesis of a new oxytrichid ciliate, Notohymena limus n. sp. were studied in vivo and after protargol impregnation. The new ciliate was isolated from the sewage sludge at Delhi Jal Board Sewage Treatment Plant located at Rithala, Delhi, India, using the non-flooded Petri dish method. N. limus n. sp. is characterized as follows: flexible dorsoventrally flattened ellipsoidal body; Notohymena-pattern undulating membranes; adoral zone of membranelles (AZM) occupied about 39% of the body length, and consists of around 26 membranelles; large and deep buccal cavity; colorless subpellicular granules present in groups and arranged around the bases of dorsal bristles; 4 macronuclear nodules; 2 micronuclei; 18 fronto-ventral-transverse (FVT) cirri in typical Oxytricha-pattern; 6 dorsal rows of bristles; 3 caudal cirri; about 16 right and 15 left marginal cirri; N. limus n. sp. is a new species on the basis of the combination of morphological, morphometric and morphogenetic characteristic features.  相似文献   

7.
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   

8.
The morphology and morphogenesis of a new saline soil hypotrichous ciliate, Urosoma quadrinucleatum n. sp., collected from northwestern China, were studied based on live observations and protargol stained specimens. The new species is characterized as follows: size in vivo 90–130 × 20–30 μm; body outline elongate-elliptical with both ends broadly rounded; four macronuclear nodules; cortical granules present; paroral in front of endoral; usually 16 frontal-ventral-transverse cirri. Urosoma quadrinucleatum n. sp. has almost the same morphogenetic characteristics as its congeners U. gigantea and U. salmastra, and differs from other three congeners whose morphogenesis is known in the formation of the frontal-ventral-transverse cirral anlagen as well as the development of marginal and dorsal kineties anlagen. The sequence differences among U. quadrinucleatum n. sp. and other Urosoma species further support the validity of the present organism as novel species. Further, U. quadrinucleatum n. sp. clusters with U. salmastra in the phylogenetic analyses based on small subunit ribosomal RNA gene (SSU rDNA) sequence data.  相似文献   

9.
This paper investigates the morphology, ontogenesis and small subunit (SSU) rRNA gene-based phylogeny of a new urostylid ciliate, Bakuella subtropica sp. n., discovered from the estuary of the Pearl River in Guangzhou, southern China. The new species is diagnosed by its elongate body, one buccal and one parabuccal cirrus, midventral complex comprised of 9–23 midventral pairs and one or two midventral rows extending to four fifths of body length, yellow-brown to yellow-greenish cortical granules and an estuary habitat. Its main ontogenetic features are: (1) in the proter, the parental adoral zone of membranelles is completely renewed by new structures and old midventral pairs join the formation of frontal-midventral-transverse cirral anlagen (FVT-anlagen); (2) in the opisthe, the oral primordium originates apokinetally, FVT-anlagen are formed besides and some old midventral cirri join the formation; (3) the anlagen for marginal rows and dorsal kineties develop intrakinetally; and (4) the numerous macronuclear nodules fuse into a single mass before dividing. Based on the SSU rDNA sequences, phylogenetic analyses show a close relationship between Bakuella subtropica sp. n., Apobakuella and Neobakuella, forming a clade separated from the other genera in the family Bakuellidae. Available morphological and ontogenetic data challenge the monophyly of Bakuellidae.  相似文献   

10.
In a study of marine ciliate diversity, we collected an Anteholosticha monilata-like population from Vietnam. To identify this population, we analyzed its morphology, some morphogenetic stages, and molecular phylogeny. Based on these data, we conclude that the Vietnamese population is new to science. Anteholosticha foissneri n. sp. resembles Anteholosticha monilata-like species considering (1) the number and arrangement of macronuclear nodules and micronuclei; (2) the presence of cortical granules; and (3) the saline habitat. However, the new species can be easily distinguished from these species by the arrangement, color, and shape of the cortical granules. The divisional morphogenesis commences with the de novo proliferation of basal bodies as a single longitudinal patch left of the posteriormost midventral cirral pair. This character state has not been reported before in Anteholosticha (based on check of the available data) and probably reflects a distinct clade within the nuclear small subunit ribosomal RNA gene tree.  相似文献   

11.
Soil samples were taken from a temporary pond located in Buenos Aires province, Argentina, during the dry phase in the summer of 2005. The ciliates were studied alive and after staining with protargol. Deviata rositae n. sp. measures 112-154 microm in length and 21-28 microm in width in vivo and has a vermiform body. The contractile vacuole is located in the mid-body on the left. The macronucleus is moniliform and there are 1-3 micronuclei. The oral apparatus is composed of 14-18 adoral membranelles and straight paroral and endoral membranes that never intersect each other. The somatic ciliature is arranged in four frontal cirri, one buccal cirrus, six long and slightly spiraled rows of cirri with the first right row extending up to the equatorial or sub-equatorial region, and two dorsal rows of dikinetids. This new species of Deviata primarily differs from its congeners by the number of macronuclear nodules and the number and disposition of the dorsal rows of dikinetids.  相似文献   

12.
We isolated a new ciliate, Bistichella variabilis n. sp., from slightly saline soil of the Yellow River Delta in China and studied it using live observation, protargol staining, and small subunit (SSU) rRNA gene sequencing. Bistichella variabilis is elongated ellipsoidal and about 220 × 70 μm in vivo, with a variable number and arrangement of cirri- ventral row VI mostly very short, but a long row observed also in one specimen, and an extra row occasionally exists besides the left or the right marginal row. Bistichella variabilis differs from all congeners except Bistichella buitkampi (Foissner, 1982) in the macronuclear pattern (four vs. two or many nodules); and from B. buitkampi by the usual oblique arrangement of transverse cirri (vs. perpendicular); and the ventral row VI mostly restricted in the posterior quarter of the cell (vs. long and stretching to the anterior quarter). Phylogenetic analyses of SSU rDNA sequences indicated that B. variabilis grouped with the clade of Orthoamphisiella breviseries and Uroleptoides magnigranulosus with high support values. Despite their distinct differences in morphology, these three species have sequence similarities of 99.5-99.7%. Nonetheless, it is still premature to assign Bistichella together with Uroleptoides to the family Orthoamphisiellidae because of the taxonomic uncertainties and undersampling.  相似文献   

13.
The morphology, morphogenesis, and molecular phylogeny of Bakuella (Pseudobakuella) guangdongica n. sp., isolated from southern China, were investigated. The new species is characterized by a body length of 150–225 μm in vivo; 35–42 adoral membranelles; 3–5 buccal, two frontoterminal, 7–12 transverse and two pretransverse ventral cirri; midventral complex comprised of 10–20 pairs and two rows extending to transverse cirri; posterior part of marginal rows slightly overlapping; colorless cortical granules about 1 μm across, arranged in small groups; soil habitat. Its main ontogenetic features are: (1) in the proter, the parental adoral zone of membranelles is completely renewed by new structures; (2) in the opisthe, the oral primordium originates apokinetally, some old midventral cirri join the formation of frontoventral-transverse cirral anlagen; (3) the anlagen for marginal rows and dorsal kineties develop intrakinetally; and (4) the numerous macronuclear nodules fuse into a single mass before dividing. Phylogenetic analyses based on the SSU rDNA sequence suggest the non-monophyly of the genus Bakuella.  相似文献   

14.
Berkleasmium crunisia sp. nov. is described from a decaying rachis of Calamus sp. (Arecaceae) from Khuan Ka Long, Satun Province, Thailand. This Berkleasmium species differs morphologically from other species in possessing subtending cells and larger conidia. The phylogenetic relationship of the genus Berkleasmium among sexual ascomycetes also was examined. Sequence analyses from 18S, 28S and ITS-5.8S rDNA were analyzed phylogenetically under maximum parsimony, Bayesian and neighbor joining criteria. Phylogenies revealed that Berkleasmium is not monophyletic. Berkleasmium micronesicum and B. nigroapicale are related to Westerdykella cylindrica and Sporormia australis, which are members of the family Sporormiaceae (Pleosporales). Other species, including our new taxon, appear to share phylogenetic affinities with other anamorphic fungi, whose classification within the Pleosporales is still obscure. Analyses of 18S, 28S, ITS (+5.8S) rDNA and combined (18S+28S) gene sequences fail to give sufficient phylogenetic resolution within the Pleosporales.  相似文献   

15.
Phylogenetic analysis of the genus Eimeria suggests that parasite and host have coevolved over broad evolutionary timescales. Here we extend this analysis by determining the 18S rDNA gene sequence of the marsupial coccidium, Eimeria trichosuri, and assessing its phylogenetic position relative to Eimeria from birds, reptiles and placental mammals. This analysis placed E. trichosuri clones in a clade that diverged before the major clade comprising species from placental mammals. The position of E.trichosuri is consistent with host phylogeny where marsupials represent an ancient evolutionary line that predates the placental mammal line.  相似文献   

16.
The morphology and main ontogenetic traits of a new stichotrich ciliate, Saudithrix terricola Foissner, AL-Rasheid and Berger n. gen., n. sp., from a terrestrial habitat in Saudi Arabia were investigated using live observation, protargol impregnation, and scanning electron microscopy. Saudithrix terricola is characterized by a large (200-350 x 70-150 microm), flexible body; an adoral zone formed like a three-quarter circle; a sickle-shaped buccal lip with a widened paroral forming a cyrtohymenid pattern with the endoral; 11 frontal and frontal-ventral cirral rows (including right marginal rows) and one left marginal row covering the ventral side; two buccal cirri; six to nine transverse cirri; three dorsal kineties; and two macronuclear nodules. The resting cyst is about 85 microm across, has a smooth wall, and a fluffy mucous layer. Most cirral anlagen originate within the parental rows and are arranged side by side, the proximal portion of the adoral zone of membranelles is reorganized, and some parental dorsal bristles are maintained. Neither the morphological nor the ontogenetic data reveal the systematic position of Saudithrix within the stichotrichs. The term multicorona is introduced and describes a frontal ciliature composed of four or more cirral bows.  相似文献   

17.
The community of myxosporeans and actinosporeans inhabiting a typical Scottish highland stream and the outflow area of an adjacent salmon hatchery was analysed on the basis of their 18S rDNA sequences. Nine myxosporeans belonging to the genera Sphaerospora, Chloromyxum, Zschokkella, Myxidium, Hoferellus and Myxobilatus were identified from mature spores in different organs of the fish species present. Twelve actinosporean types belonging to the collective groups of neoactinomyxum, aurantiactinomyxon, raabeia, echinactinomyxon and synactinomyxon were found to be released from oligochaete worms collected from sediments. Twenty of the 21 sequences obtained from these myxozoans are new entries to the myxozoan database, and the genera Chloromyxum, Hoferellus and Myxobilatus were entered for the first time. Study of the molecular relationships between the different taxa and with other myxozoan sequences available showed that the myxosporeans inhabiting the urinary system clearly cluster together, independently of host species or spore morphology. However, the sequences of the two Sphaerospora species encountered show considerable differences from other members of this group and all other freshwater myxosporeans, and they were found to occupy an ancestral marine position. Three actinosporeans, i.e. Neoactinomyxum eiseniellae, Aurantiactinomyxon pavinsis and Raabeia 'type 3' were found to represent alternate life cycle stages of Chloromyxum sp., Chloromyxum truttae and Myxidium truttae, respectively (approximately 1400 identical base pairs each). Three other actinosporeans encountered (two echinactinomyxon and one raabeia type) showed over 92% sequence identity with myxosporeans from GenBank, whereas all other actinosporeans formed a closely related group devoid of any known myxosporeans.  相似文献   

18.
A new marine peritrich ciliate, Pseudovorticella sinensis n. sp. was isolated from a shrimp-farming pond in the littoral area of Qingdao, China. The morphology, infraciliature, and silverline system were studied based on living and silver-impregnated specimens. This species is characterized by (1) an elongated bell-shaped body that measures 50-60 x 35-45 microm in vivo, (2) one large, ventrally located contractile vacuole, and (3) a pellicle covered by a layer of transparent, cortical vesicles. The number of transverse silverlines from the peristomial area to the aboral ciliary wreath is 26-32, and from the aboral ciliary wreath to the scopula is 12-15. The stalk measures about 160-250 microm long x 5-6 microm wide. The spasmoneme has one row of conspicuous thecoplasmic granules, which are about 0.8 microm in diameter.  相似文献   

19.
The traditional phylogeny of the coral-inhabiting barnacles, the Pyrgomatidae, is based on morphological characteristics, mainly of the hard parts. It has been difficult to establish the phylogenetic relationships among Pyrgomatidae because of the apparent convergence of morphological characteristics, and due to the use of non-cladistic systematics, which emphasize ancestor-descendant relationships rather than sister-clade relationships. We used partial sequences of two mithochondrial genes, 12S rDNA and 16S rDNA, and a nuclear gene, 18S rDNA, to infer the molecular phylogeny of the pyrgomatids. Our phylogenetic results allowed us to reject previous classifications of Pyrgomatidae based on morphological characteristics. Our results also suggested the possibility of paraphyly of the Pyrgomatidae. The hydrocoral barnacle Wanella is not found on the same clade as the other pyrgomatids, but rather, with the free-living balanids. The basal position of Megatrema and Ceratoconcha is supported. The archeaobalanid Armatobalanus is grouped with Cantellius at the base of the Indo-Pacific pyrgomatines. Fusion of the shell plate and modification of the opercular valves are homoplasious features that occurred more than three times on different clades. The monophyly of the "Savignium" group, comprising four nominal genera, is also not supported, and the different taxa are placed on different clades.  相似文献   

20.
Phylogenetic relationships of (19) serpulid taxa (including Spirorbinae) were reconstructed based on 18S rRNA gene sequence data. Maximum likelihood, Bayesian inference, and maximum parsimony methods were used in phylogenetic reconstruction. Regardless of the method used, monophyly of Serpulidae is confirmed and four monophyletic, well-supported major clades are recovered: the Spirorbinae and three groups hitherto referred to as the Protula-, Serpula-, and Pomatoceros-group. Contrary to the taxonomic literature and the hypothesis of opercular evolution, the Protula-clade contains non-operculate (Protula, Salmacina) and operculate taxa both with pinnulate and non-pinnulate peduncle (Filograna vs. Vermiliopsis), and most likely is the sister group to Spirorbinae. Operculate Serpulinae and poorly or non-operculate Filograninae are paraphyletic. It is likely that lack of opercula in some serpulid genera is not a plesiomorphic character state, but reflects a special adaptation.  相似文献   

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