Morphology and Morphogenesis of Strobilidium caudatum (Fromentel), Meseres corlissi N. Sp., Halteria grandinella (Müller), and Strombidium rehwaldi N. Sp., and a Proposed Phylogenetic System for Oligotrich Ciliates (Protozoa,Ciliophora)1

ABSTRACT. The morphology and morphogenesis of some oligotrichs were investigated using protargol impregnation, silver carbonate impregnation and scanning electron microscopy. The somatic kineties of Strobilidium caudatum form a spiral at the posterior pole. Strobilidiids without such a spiral are transferred to the genus Rimostrombidium. Fourteen new combinations and a nomen novum, Strobilidium kahli, are necessary, Meseres corlissi n. sp. is characterized by eight somatic kineties composed of long cilia which are not fused to “bristles” as they are in Halteria. Strombidium oblongum shows similar characteristics and is thus combined with Meseres. Strombidium rehwaldi n. sp. has an anterior and an equatorial girdle of extrusomes. The morphogenesis of Meseres and Halteria is very similar, i.e. the entire somatic ciliature and the oral primordium originate apokinetally on the cell surface; the parental somatic ciliature is resorbed. In strobilidiids and tintinnids, the oral anlagen develop in a subsurface pouch and the parental somatic kineties, which are not resorbed, elongate by intrakinetal proliferation of basal bodies. In strombidiids, the oral primordium develops in an intracellular sac or tube. These morphogenetic peculiarities and distinct morphologic characters (e.g. arrangement of adoral membranelles) were applied in constructing a phylogenetic system for oligotrichs using hypotrichs as outgroup. This shows that halteriids are more closely related to hypotrichs than they are to other oligotrichs. The Halteriidae are thus raised to ordinal and subclass ranks, Halteriida n. ord., Halteriia n. subcl.     

Phylogeny of three choreotrich genera (Protozoa,Ciliophora, Spirotrichea), with morphological,morphogenetic and molecular investigations on three strobilidiid species

Liu, W., Yi, Z., Lin, X., Warren, A. & Song, W. (2012). Phylogeny of three choreotrich genera (Protozoa, Ciliophora, Spirotrichea), with morphological, morphogenetic and molecular investigations on three strobilidiid species. —Zoologica Scripta, 41, 417–434. The phylogenetic relationships among three strobilidiid genera, namely Strobilidium, Rimostrombidium and Pelagostrobilidium, are investigated using a combination of morphological, morphogenetic and molecular data. The results indicate that all three genera belong to the same lineage, in which Rimostrombidium evolved first and Strobilidium and Pelagostrobilidium derived later. Improved genus diagnoses for Rimostrombidium and Pelagostrobilidium are supplied. The curved kinety 2 and the caudal spiralling of some somatic kineties are confirmed as generic characters for Pelagostrobilidium and Strobilidium, respectively. In addition, the morphology and morphogenesis of three species, namely R. veniliae ( Montagnes & Taylor, 1994 ) Petz et al., 1995 , P. paraepacrum sp. n. and P. minutum sp. n., isolated from the South China Sea are described. Pelagostrobilidium paraepacrum sp. n. is characterized by the presence of six somatic kineties, 30–32 external and two internal membranelles. Pelagostrobilidium minutum sp. n. is characterized by its extremely small body size, four somatic kineties, and in having one internal and 19–21 external membranelles. Rimostrombidium conicum Kahl, 1932 is transferred to the genus Pelagostrobilidium as P. conicum (Kahl, 1932) comb. nov.     

Characterization of Euplotes lynni nov. spec., E. indica nov. spec. and description of E. aediculatus and E. woodruffi (Ciliophora,Euplotidae) using an integrative approach

Four species belonging to the genus Euplotes have been investigated, namely: E. lynni nov. spec., E. indica nov. spec., E. aediculatus, and E. woodruffi. All populations are from India and were investigated using morphological and molecular markers. The phylogenetic relationships were inferred from small subunit ribosomal rRNA gene (SSU rRNA), internal transcribed spacer (ITS) region, and mitochondrial cytochrome c oxidase subunit I (COI) gene. Predicted secondary structure models for two new species using the hypervariable region of the SSU rRNA gene and ITS2 region support the distinctness of both species. Morphological characters were subjected to principal component analysis (PCA) and genetic variations were studied in-depth to analyze the relatedness of the two new species with their congeners. An integrative approach combining morphological features, molecular analysis, and ecological characteristics was carried out to understand the phylogenetic position of the reported species within the different clades of the genus Euplotes.     

Updated hypothesis on the evolution of oligotrichid ciliates (Ciliophora, Spirotricha, Oligotrichida) based on somatic ciliary patterns and ontogenetic data

The two recently established genera ApostrombidiumXu et al., 2009 and VaristrombidiumXu et al., 2009 and the analysis of ontogenetic data in Strombidium constrictum, S. montagnesi, S. wilberti, Omegastrombidium elegans, and Paratontonia gracillima necessitated a revision of the hypothesis about the somatic ciliary pattern evolution in oligotrichid ciliates. As a consequence, the species-rich genus Strombidium was split, establishing two genera for species with a horizontal girdle kinety posterior to the oral primordium: Opisthostrombidium nov. gen. with the extrusome attachment sites along the anterior margin of the girdle kinety and posterior to the oral primordium and Foissneridium nov. gen. with the extrusome attachment sites distinctly apart from the girdle kinety and anterior to the oral primordium. The ontogenetic data revealed that the Ω-shaped girdle kinety pattern evolved convergently from the Pseudotontonia pattern with its horizontal girdle kinety in the tailed genus Paratontonia and from the Novistrombidium pattern with its dextrally spiralled girdle kinety in the tailless genus Omegastrombidium. The somatic ciliary pattern of the latter genus probably gave rise to the patterns of Apostrombidium and Varistrombidium.     

Morphological studies indicate that Pleuronema grolierei nov. spec. and P. coronatum Kent, 1881 represent different sections of the genus Pleuronema (Ciliophora: Scuticociliatida)

The morphology, infraciliature and silverline system of two marine scuticociliates, Pleuronema grolierei nov. spec. and Pleuronema coronatum Kent, 1881, isolated from the sand beaches along the coast of Qingdao, China, were investigated using live observation and silver impregnation methods. Ciliates of the genus Pleuronema are normally easily recognized by their large sail-like paroral membrane. In this respect, P. coronatum is a typical member of the genus, whereas P. grolierei is unique in having much shorter cilia in the paroral membrane, which, in consequence, is rather inconspicuous. Nevertheless, details of the infraciliature confirm that P. grolierei belongs to the genus Pleuronema. Within the genus Pleuronema, the posterior end of the anterior fragment of the second membranelle (M2a) may be either straight, as in P. grolierei, or hooked-shaped, as in P. coronatum, providing a criterion for recognizing two sections within the genus. Based on the current study and previous reports, we propose that three nominal forms, Pleuronema balli Small and Lynn, 1985, Pleuronema smalli Dragesco, 1968 and Pleuronema borrori Dragesco, 1968 should be synonymized with P. coronatum.     

Redescription of Rigidohymena inquieta (Stokes, 1887) Berger, 2011 as Metahymena inquieta gen. nov., comb. nov. (Ciliophora,Hypotricha) Based on Morphology,Morphogenesis, and Molecular Phylogeny

The morphology and morphogenesis of Rigidohymena inquieta (Stokes, 1887) Berger, 2011, isolated from a lawn soil in the campus of the University of Ulsan, Korea, was studied, using live observation and protargol impregnation. The molecular phylogeny was studied based on the SSU rRNA gene sequences. The morphology of the Korean population of R. inquieta matches the previously known populations; however, the morphogenetic pattern shows differences to the species R. candens in the involvement of cirrus V/3 in the anlagen formation. A novel genus namely Metahymena gen. nov. has been erected for the present species based on the ontogenetic difference, and the new combination Metahymena inquieta gen. nov., comb. nov. is proposed. The morphology, morphogenesis, distribution, and phylogeny of M. inquieta are presented. The morphologic and morphogenetic data corroborate the phylogenetic analyses as M. inquieta clusters among the stylonychid ciliates in a clade distant from Rigidohymena candens.     

Taxonomy,morphology and molecular systematics of a new oligotrich ciliate,Williophrya maedai gen. nov., sp. nov., with redescriptions of Strombidium basimorphum and Pseudotontonia simplicidens (Protozoa,Ciliophora, Oligotrichia)

The morphology and small subunit rRNA (SSrRNA) gene sequence of a marine oligotrich ciliate, Williophrya maedai gen. nov., sp. nov., are reported. The new genus Williophrya is characterized by the adoral zone with no differentiation of membranelles, and the reduced somatic ciliature which comprises a bipartite girdle kinety only. In addition, the in vivo morphologies of two other oligotrichs, namely Strombidium basimorphum Martin & Montagnes, 1993 and Pseudotontonia simplicidens (Lynn & Gilron, 1993 Lynn, D. H. and Gilron, G. L. 1993. Strombidiid ciliates from coastal waters near Kingston Harbour, Jamaica (Ciliophora, Oligotrichia, Strombidiidae). Journal of the Marine Biological Association of the United Kingdom, 73: 47–65. [Crossref] , [Google Scholar]) Agatha, 2004, are reported for the first time based on Chinese populations. Improved diagnoses of both species are supplied. The phylogenetic position of Williophrya maedai is investigated based on SSrRNA gene sequence data. These show that: (1) Williophrya maedai is most closely related to Strombidium purpureum and S. apolatum; (2) Williophrya is assigned to the family Strombidiidae although it has some unique morphological features regarding its oral and somatic ciliatures.     

Morphology,Ontogeny, and Phylogeny of Two Brackish Urostylid Ciliates (Protist,Ciliophora, Hypotricha)

The diversity of hypotrichous ciliates has encouraged numerous researchers to use a combination of morphological, morphogenetic, and phylogenetic data to provide a better understanding of the evolutionary relationships within this complex group. In this study, we investigate the morphology and morphogenesis of Pseudourostyla subtropica sp. nov., isolated from mangrove wetland. The new species can be distinguished from its congeners by the huge body size, many more adoral membranelles and marginal cirral rows, and numerous macronuclear nodules. In addition, we provide a morphological characterization of a population of Pseudourostyla nova Wiackowski 1988 from an estuarine habitat. The main events during binary fission of P. subtropica sp. nov. and the Chinese population of P. nova are also revealed to be conservative. The morphological, ontogenetic, and phylogenetic analyses based on the SSU rDNA sequences corroborate the monophyly of Pseudourostyla Borror, 1972, which corresponds well with previous research. The phylogenetic analyses also show that Pseudourostyla and Hemicycliostyla Stokes, 1886, both of which are assigned to the family Pseudourostylidae based on morphological and morphogenetic data, in fact fall into separated clades. The approximately unbiased tests, however, do not reject the possibility that the family Pseudourostylidae is a monophyletic lineage.     

Peregrinacarus reticulatus gen. nov. spec. nov., a freshwater halacarid mite (Acari,Halacaridae) from Marion Island

Peregrinacarus reticulatus gen. nov. spec. nov. is described. The genus belongs to the subfamily Halacarinae and is related to the marine genus Halacarellus. The most marked character is the absence of a ventromedial seta on tarsus I. P. reticulatus supposedly is a very recent immigrant in diluted brackish and fresh water. This revised version was published online in July 2006 with corrections to the Cover Date.     

Cotterillia bromelicola nov. gen., nov. spec., a gonostomatid ciliate (Ciliophora, Hypotricha) from tank bromeliads (Bromeliaceae) with de novo originating dorsal kineties

Cotterillia bromelicola nov. gen., nov. spec. was discovered in the tanks of the Mexican bromeliad Tillandsia heterophylla. Its morphology, ontogenesis, and 18S rDNA were studied with standard methods. Cotterillia has many cirral rows on both sides of the body. Uniquely, and thus used to diagnose the new genus Cotterillia, it has dorsal kineties originating de novo, producing neokinetal waves where the parental dorsal kineties reorganize to “combined rows”, consisting of dorsal bristles anteriorly and of cirri posteriorly. Thus, up to four generations of bristles and cirri occur on the dorsal body surface. Cotterillia bromelicola has a gonostomatid body and adoral zone of membranelles, while the dense ciliature and the neokinetal waves resemble kahliellid hypotrichs. However, the de novo origin of anlage 1 and the molecular analyses show convincingly that Cotterillia belongs to the GonostomatidaeSmall and Lynn, 1985, for which an improved diagnosis is provided. Thus, neokinetal waves originated several times independently. The molecular differences between Trachelostyla, Gonostomum, and Cotterillia are small (≤5%) compared to their distinct morphologies and ontogeneses, suggesting that the 18S rDNA underestimates generic diversity. Our study emphasizes the need of combined morphological, ontogenetic, and molecular investigations to unravel the complex phylogeny and evolution of hypotrich ciliates.     

高原姬鼠一新艾美球虫记述(顶复合门,艾美球虫科)

粪检云南省昆明市太平镇捕获的31只高原姬鼠Apodemus chevrieri,在9只高原姬鼠中共发现了2种艾美球虫,自然感染率为29%,其中1种被命名为新种:齐氏艾美球虫Eimeria chevrieri sp.nov.。齐氏艾美球虫孢子化的卵囊椭圆形,大小为21·2μm×16·3μm(22·2~19·7μm×17·3~15·6μm)。卵囊壁光滑,单层,厚约1·0μm;无胚孔和卵囊余体。有1~2个极体,极体形状不规则,直径1·0~2·0μm。卵圆形的孢子囊大小为11·2μm×7·5μm(12·3~10·3μm×8·3~6·8μm),有孢子囊余体,且主要分布在2个子孢子的中间,斯氏体扁豆形,大小为1·0μm×0·3μm,亚斯氏体亚球形,大小为2·5μm×1·5μm。子孢子在孢子囊里面头尾相接,在其宽端有1个明显的反光体,直径约3μm。模式标本保存在云南大学标本馆。齐氏艾美球虫,新种Eimeria chevrieri sp·nov.(图1~2,4)寄生于姬鼠属,具有椭圆形的卵囊,卵囊壁具有光滑、无色、单层特点的艾美球虫有3种:E.gomurica Musaev and Veisov,1963,E.kaunensis Arnastauskiene et al.,1978和E.gandobica Musaev and Veisov,1965。E.gomurica、E.kaunensis与本种的主要区别是卵囊较小且有卵囊余体;E.gandobica与本种的主要区别是卵囊呈宽椭圆形,卵囊和孢子囊较小(19·0μm×16·8μmvs·21·2μm×16·3μm;8·0μm×5·0μmvs·11·2μm×7·5μm),孢子囊余体少,无反光体和亚斯氏体。寄生于姬鼠属,具有椭圆形的卵囊,卵囊壁具有光滑、2层特点的艾美球虫有3种:E.alorani Hurková et al.,2005、E.apodemi Pell啨rdy1974和E.zaurica Musaev and Veisov,1965。E.zaurica与本种的主要区别是具有卵囊余体;E.alorani的卵囊和孢子囊比本种大的多(26·9μm×19·3μmvs.21·2μm×16·3μm),且其孢子囊余体形成一个直径约4~5μm的球状结构;E.apodemi的孢子化卵囊呈宽椭圆形,经常不对称,无极体和斯氏体。该种区别其它种的关键特征是:1)孢子化卵囊椭圆形,卵囊壁光滑、单层、无色;2)有极体;3)孢子囊有亚斯氏体。模式标本,含孢子化卵囊的齐氏姬鼠粪便保存在云南大学生物系,标本编号:2006047;齐氏姬鼠标本保存于云南大学标本馆,标本编号20060081。词源:种名源自宿主种名。     

Morphology and infraciliature of two new marine ciliates, Paracyrtophoron tropicum nov. gen., nov. spec. and Aegyria rostellum nov. spec. (Ciliophora, Cyrtophorida), isolated from tropical waters in southern China

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.     

Taxonomy and molecular phylogeny of three freshwater scuticociliates,with descriptions of one new genus and two new species (Protista,Ciliophora, Oligohymenophorea)

Three freshwater scuticociliates, Apouronema harbinensis gen. nov. spec. nov., Cyclidium vorax spec. nov., and C. glaucoma Müller, 1773, collected from rivers in Hulan District, Harbin, northeastern China, were investigated using morphological and phylogenetic criteria. Apouronema gen. nov., assigned to the family Uronematidae, is mainly distinguished from the other genera of the family by its paroral membrane extending anteriorly to the middle of membranelle 1. Apouronema harbinensis spec. nov. is defined by body size in vivo about 45–55 × 20–25 μm, buccal field about 70–80% of cell length; 12 or 13 somatic kineties; membranelle 1 having two rows, with 16–18 basal bodies in each kinety; membranelle 2 and membranelle 3 both having two rows each; scutica X-shaped with five pairs of basal bodies. Cyclidium vorax spec. nov. is characterized by the following features: body size 35–40 × 18–20 μm in vivo; 9 or 10 somatic kineties; membranelle 1 having two longitudinal rows, much shorter than M2; M2 triangle-shaped. The phylogenetic analyses show that: (1) Apouronema clustered in the Uronematidae clade, and grouped with genera Uronemita and Uronema; (2) Cyclidium vorax spec. nov. grouped with C. glaucoma and C. sinicum, which supports the assignment of the new species to the genus Cyclidium; (3) Cyclidium remains non-monophyletic with the addition of the new sequence.     

Evolution of ciliary patterns in the Oligotrichida (Ciliophora, Spirotricha) and its taxonomic implications

Although the somatic ciliature of the Oligotrichida typically comprises only a girdle and ventral kinety, a considerable diversity of ciliary patterns occurs. The four main girdle kinety patterns are identically found in tailed and tail-less species. The contractile tail has a complicated and unique ultrastructure and is potentially useful for the cell's movement and/or stabilization during feeding. Accordingly, I assume that this structure has evolved only once, namely, in the Tontoniidae nov. fam., and that the different girdle kinety patterns developed convergently in the tailed and tail-less taxa. Further distinct features suggest the establishment of the families Cyrtostrombidiidae nov. fam. (with cyrtos-like pharyngeal fibres and lack of ventral membranelles and endoral) and Pelagostrombidiidae nov. fam. (with neoformation organelle). An attempt is made to reconstruct the evolution of the kinety patterns based on morphologic, ontogenetic, and ultrastructural data. Some genera of tail-less Oligotrichida base on differences in the ciliary pattern; Omegastrombidium nov. gen. is erected for a further girdle kinety pattern. Likewise, the tailed genus Tontonia is split, resulting in two new genera, viz., Pseudotontonia nov. gen. and Spirotontonia nov. gen. Furthermore, the genus Spirostrombidium is split due to the different origin of the parallel course of girdle and ventral kinety, and Parallelostrombidium nov. gen. is established. However, the genus Thigmostrombidium is rejected because its enlarged thigmotactic membranelles are interpreted as an adaptation to the benthic lifestyle, which occurred several times within different girdle kinety patterns.     

Two new species of cossonine weevils,Araucarius kuscheli spec. nov. and A. crassipunctatus spec. nov. (Coleoptera: Curculionidae) from southern Brazil

The occurrence of cossonine weevils of the genus Araucarius Kuschel 1966 is limited to South American Araucaria trees. Adults and larvae of two new species, Araucarius kuscheli spec. nov. and A. crassipunctatus spec. nov. have been found under the bark of Araucaria angustifolia trees in São Francisco de Paula, Rio Grande do Sul, Brazil. A key for the adults of the genus Araucarius including the two new species and the already known two Brazilian and four Chilean species is presented.     

吉林省蓝藻门真枝藻属三新种

报道了采自吉林省的蓝藻门真枝藻属三新种：波纹真枝藻,拟小真枝藻,悦目真枝藻。波纹真枝藻丝体边缘常呈波纹状,主丝体宽 80～100 μm;拟小真枝藻主丝体宽 60～80 μm,分枝宽 30～45 μm,其胶被幼时黄褐色,成熟后无色;悦目真枝藻的匍匐丝体由数条丝体通过侧面粘合在一起,每条丝体宽 15～26 μm。