Spathidium seppelti foissneri nov. subspec., Spathidium simplinucleatum nov. stat., and Dileptus americanus Kahl, 1931, one new and two poorly known soil gymnostome ciliates from soils of Slovakia

The morphology and infraciliature of three soil gymnostome ciliates, Spathidium seppelti foissneri nov. subspec., Spathidium simplinucleatum nov. stat., and Dileptus americanus, collected from Slovakia, were investigated using live observation and protargol impregnation. S. seppelti foissneri is distinguished from its congeners by a combination of characters including: distinctly spatulate shape with convex oral bulge; 25 ellipsoidal, scattered macronuclear nodules; an average of 23 ciliary rows, 3 anteriorly differentiated to form a dorsal brush occupying 25% of the body length; and rod-shaped to slightly ellipsoidal extrusomes measuring about 5 x 0.5 microm. S. simplinucleatum is about 110 x 50 microm in vivo, characterized by solid, concave oral bulge, with the impression of doubled oral bulge in right side, macronuclear tortuous strand, usually 30 ciliary rows, 3 anteriorly differentiated to form a dorsal brush, and about 7 microm long rod-shaped extrusomes. S. simplinucleatum is highly variable in body size and length of monokinetidal bristle tail. Dileptus americanus is about 300 x 50 microm in vivo and differs from its congeners by a combination of characters including two macronuclear segments with a single micronucleus in between, two contractile vacuoles in dorsal side of trunk, two size types of rod-shaped extrusomes, a proboscis which occupies about 37% of body length, circular oral opening, and an average of 22 ciliary rows, of which up to 4 are differentiated to form a dorsal brush.     

Ontogenesis of Dileptus terrenus and Pseudomonilicaryon brachyproboscis (Ciliophora, Haptoria)

ABSTRACT. Dileptids are haptorid ciliates with a conspicuous proboscis belonging to the oral apparatus and carrying a complex, unique ciliary pattern. We studied development of body shape, ciliary pattern, and nuclear apparatus during and after binary fission of Dileptus terrenus using protargol impregnation. Additional data were obtained from a related species, Pseudomonilicaryon brachyproboscis . Division is homothetogenic and occurs in freely motile condition. The macronucleus is homomeric and condenses to a globular mass in mid-dividers. The proboscis appears in late mid-dividers as a small convexity in the opisthe's dorsal brush area and maturates post-divisionally. The oral and dorsal brush structures develop by three rounds of basal body proliferation. The first round generates minute anarchic fields that will become circumoral kinetofragments, while the second round produces the perioral kinety on the right and the preoral kineties on the dorsal opisthe's side. The dorsal brush is formed later by a third round of basal body production. The formation of various Spathidium -like body shapes and ciliary patterns during ontogenesis and conjugation of Dileptus shows a close relationship between spathidiids and dileptids. On the other hand, the peculiarities of the dileptid morphology and ontogenesis indicate a long, independent evolution.     

Morphological and molecular characterization of the name-bearing type species Rimaleptus binucleatus (Kahl, 1931), with a phylogenetic re-analysis of dileptid evolutionary history (Ciliophora: Litostomatea: Rhynchostomatia)

We collected Rimaleptus binucleatus from soil in the surroundings of the town of Ulsan, South Korea. Its morphology and 18S rRNA gene were studied using standard methods. This possibly widely distributed species is characterized by: (i) a size of about 170–400 × 20–65 μm; (ii) a narrowly to cylindrically dileptid body with proboscis occupying about 30–65% of body length; (iii) two dorsal contractile vacuoles; (iv) two size groups of rod-shaped extrusomes; and (v) about 18–29 ciliary rows, 4–6 of them anteriorly differentiated into a staggered dorsal brush. Phylogenetic analyses of five new rhynchostomatian 18S rRNA gene sequences supported monophylies of the orders Tracheliida and Dileptida, but revealed that the genera Rimaleptus and Pseudomonilicaryon are polyphyletic. Monophyly of genera with two macronuclear nodules was consistently rejected, but monophylies of dileptids with many scattered macronuclear nodules and of dileptids with moniliform macronucleus and multi-rowed dorsal brush could not be excluded by statistical topology tests. Nevertheless, phylogenetic network analyses indicated considerable conflict in the phylogenetic signal provided by the 18S rRNA gene to resolve unambiguously relationships among dileptid genera.     

Morphology and Molecular Phylogeny of a New Haptorian Ciliate,Chaenea mirabilis sp. n., with Implications for the Evolution of the Dorsal Brush in Haptorians (Ciliophora,Litostomatea)

We discovered a new haptorian ciliate, Chaenea mirabilis sp. n., in brackish water collected near the town of Busan, Korea. Its morphology was studied using standard taxonomical methods and its phylogenetic relationships were assessed by phylogenetic analysis of the 18S rRNA gene. Chaenea mirabilis is distinguished from all congeners by the combination of the following traits: (i) a narrowly bursiform to flask‐shaped, 60–100 μm long body; (ii) 11–21 doughnut‐shaped or sometimes horseshoe‐shaped macronuclear nodules; (iii) two types of extrusomes: type I is rod‐shaped and 6–8 μm long, while type II is narrowly to broadly teardrop‐shaped and only 1.5–2 μm long; (iv) highly refractive special granules tightly arranged between the first and second brush row, forming a conspicuous bulge; and (v) 12–13 somatic kineties. In the 18S rRNA gene phylogeny, C. mirabilis clustered with full support with other congeners. However, there was no statistical support for classification of Chaenea into the families Fuscheriidae, Acropisthiidae, or Trachelophyllidae, but a sister relationship with the Lacrymariidae could not be excluded. Therefore, we establish a new family, Chaeneidae, within the order Lacrymariida. This affiliation is strongly corroborated by the distinctly subapical dorsal brush bearing cilium‐like bristles.     

Urotricha psenneri n. sp. and Amphileptus piger (Vuxanovici, 1962) n. comb., two planktonic ciliates (Protozoa, Ciliophora) from an oligotrophic lake in Austria

Two euplanktonic ciliates, Urotricha psenneri n. sp. (Prostomatida) and Amphileptus piger (Vuxanovici, 1962) n. comb. (Pleurostomatida), were discovered in the surface plankton of the oligotrophic Lake Traunsee in Austria. Their morphology and infraciliature were studied in live cells as well as in specimens impregnated with protargol and silver nitrate. Urotricha psenneri is a small urotrichid, less than 50 microm length and with a single caudal cilium. It is unique in having (i) a massive oral basket projecting as a conspicuous bulge with cylindrical microfibrillar annulus and (ii) a curved brosse row 1 in the broad, barren circumoral area. Amphileptus piger (Vuxanovici, 1962) is about 55 x 13 microm in vivo, has two macronuclear nodules with a single micronucleus in between in the posterior body half, has a single contractile vacuole with a terminal excretory pore, and few, but thick and thus highly conspicuous extrusomes. The amphileptid ciliary pattern (spica) is difficult to recognise due to the widely spaced basal bodies.     

Morphology,Conjugation, and Postconjugational Reorganization of Dileptus tirjakovae n. sp. (Ciliophora,Haptoria)

ABSTRACT. We studied the morphology, conjugation, and postconjugational reorganization of a new haptorid ciliate, Dileptus tirjakovae n. sp., using conventional methods. Dileptus tirjakovae is characterized by two abutting, globular macronuclear nodules and scattered brush kinetids. Conjugation is similar to that in congeners, that is, it is temporary, heteropolar, and the partners unite bulge‐to‐bulge with the proboscis. Some peculiarities occur in the nuclear processes: there are two synkaryon divisions producing four synkaryon derivatives, of which two become macronuclear anlagen, one becomes the micronucleus, and one degenerates. Unlike spathidiids, D. tirjakovae shows massive changes in body shape and ciliary pattern before, during, and after conjugation: early and late conjugants as well as early exconjugants resemble Spathidium, while mid‐conjugants resemble Enchelyodon. These data give support to the hypothesis that spathidiids evolved from a Dileptus‐like ancestor by reduction of the proboscis. Dileptus tirjakovae exconjugants differ from vegetative cells by their smaller size, stouter body, shorter proboscis, and by the lower number of ciliary rows, suggesting one or several postconjugation divisions. Although 83% of the exconjugants have the vegetative nuclear pattern, some strongly deviating specimens occur and might be mistaken for distinct species, especially because exconjugants are less than half as long as vegetative cells.     

Morphology and ciliary pattern of some rare haptorid ciliates, with a description of the new family Kamburophryidae (Protists, Haptoria)

We investigated three rare haptorid ciliates, viz., Lagynophrya gibba Kahl (1935), Enchelys lajacola nov. spec., and Spathidium implicatum Kahl (1930), using live observation, silver impregnation, morphometry, and scanning electron microscopy. Lagynophrya gibba, which was rediscovered in peatland soil from Iceland, is referred to a new genus, Kamburophrys, and a new family, Kamburophryidae, based on a unique organelle, the brush membranoid. This structure is near the dorsal brush and composed of very narrowly spaced cilia, about 5 μm long. The genus Kamburophrys has a unique combination of features, viz., an oral cone on the oral bulge, an oblique circumoral kinety, and a subapical hump carrying the three-rowed dorsal brush and the brush membranoid. The Kamburophryidae possibly belong to the order Spathidiida. Enchelys lajacola was discovered in mud from granitic rock-pools (Lajas) in Venezuela, South America. The new species is characterized by a bottle-like shape, a macronucleus with the shape of a curved strand, a heterostichad dorsal brush, and rod-shaped toxicysts. Spathidium implicatum, which was rediscovered in an ephemeral meadow puddle near Salzburg city centre, is neotypified and referred to the genus Apertospathula because it has an open circumoral kinety.     

The Predatory Behavior of Dileptus anser*

SYNOPSIS. A motion picture study of the feeding behavior of Dileptus anser upon Colpidium campylum revealed that feeding begins shortly before dawn (about 4:30 a.m. Pacific DST in July and August) and continues until bright daylight, terminating sharply between 8:30 and 9:00 a.m. Little or no feeding occurs at any other time during a 24 hr cycle. A “biological clock” phenomenon is suggested, but was not further investigated. Attack by Dileptus often results in “escape” behavior by Colpidium. When struck (usually antero-dorsally), the latter rotates, usually adhering to the microscope slide at the end which was struck, constricting the undamaged part of the body, pulling free, swimming off and regenerating if not again struck by Dileptus. After successive attacks and feeding, the proboscis of Dileptus becomes adhesive and sticks to the microscope slide near its tip. Dileptus jerks the proboscis free, sacrificing the attached portion. Several successive such truncations may occur as Dileptus feeds, so that at the end of a feeding period only a stub of the proboscis may remain. The entire proboscis is regenerated before the next feeding period begins. Ingestion of Colpidium by Dileptus appears to involve 2-way streaming of cytoplasm which results in a retreat of cytoplasm from the region of the cytostome toward the rear, forming an ingestion cavity. The cytostome simultaneously opens widely to accommodate passage of prey, even before the prey reaches the cytostome, and is often opened wider than the diameter of the prey. Ingestion is assumed to involve protoplasmic movements other than those only of the fibrillar organelles in the region of the cytostome.     

Morphology and Phylogeny of Two New Pleurostomatid Ciliates,Epiphyllum shenzhenense n. sp. and Loxophyllum spirellum n. sp. (Protozoa,Ciliophora) from A Mangrove Wetland,South China

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.     

The apertospathulidae, a new family of haptorid ciliates (protozoa, ciliophora)

We studied the morphology of three rare haptorid ciliates, using live observation and silver impregnation: Apertospathula verruculifera n. sp., Longispatha elegans n. gen., n. sp., and Rhinothrix porculus (Penard, 1922) n. gen., n. comb. Simple ethanol fixation (50-70%, v/v) is recommended to reveal the ciliary pattern of "difficult" ciliates, such as R. porculus, by protargol impregnation. The three genera investigated have a distinct feature in common, viz., a lasso-shaped oral bulge and circumoral kinety, where the right half is slightly to distinctly longer than the left and the circumoral kinety is open ventrally. Thus, they are united in a new spathidiid family, the Apertospathulidae n. fam., which probably evolved from a Bryophyllum-like ancestor by partial reduction of the oral bulge and circumoral kinety. Apertospathula verruculifera has a wart-like process, the palpus dorsalis, at the anterior end of the dorsal brush. The right branch of the circumoral kinety is only slightly longer than the left one. Longispatha elegans has a straight oral bulge and circumoral kinety, the right branch of which extends to the posterior end of the body while the left branch ends in the anterior third of the body. Rhinothrix porculus, a curious ciliate with a snout-like dorsal elongation of the oral bulge, the palpus oralis, has a highly characteristic ciliary pattern: the oral pattern is as in Longispatha, but the bulge and circumoral kinety extend spirally to the posterior end of the body while the somatic kineties course meridionally. This is achieved by inserting some shortened kineties in the curves of the oral bulge.     

Kiitricha minuta n. sp., a peculiar hypotrichous ciliate (Ciliophora, Spirotrichea) from the Yellow Sea

The morphology and infraciliature of a new ciliate, Kiitricha minuta n. sp., isolated from the Yellow Sea, were investigated using live observation and protargol impregnation. Kiitricha minuta represents a third member of the rarely known order Kiitrichida. It is unique in the subclass Hypotrichia in having many rows of small uniform cirri along the right side of the body and the dorsal kineties composed of dikinetids, most of which bear two cilia. Kiitricha minuta n. sp. is ovoid and measures about 60 x 45 microm in vivo. It has a huge buccal cavity occupying about 80% of the body length, numerous body extrusomes, one macronucleus and two micronuclei, 27-27 adoral membranelles, 9-12 frontoventral cirral rows, a submarginal row of 7-9 cirri, 6 or 7 transverse cirri, and roughly 7-9 dorsal kineties. This new species differs distinctly from its only congener Kiitricha marina by its smaller size (60 microm vs. 80-150 microm), the presence of body extrusomes (vs. absent), the different macronuclear pattern (one vs. two nodules), and the lower number of frontoventral cirral rows (9-12 vs. 21-26), which terminate at the anterior two-thirds of body (vs. extend to the posterior). The new term "submarginal cirral row" is introduced to distinguish from the marginal cirral row in typical hypotrichs sensu lato. Based on our new observations and the literature, an improved diagnosis for the genus Kiitricha is provided and its phylogenetic importance is discussed.     

Two new marine pleurostomatid ciliates from China,Amphileptus gui nov. spec. and Amphileptus yuianus nov. spec. (Ciliophora,Pleurostomatida)

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).     

Morphological and taxonomical studies on two soil haptorid ciliates (Ciliophora, Litostomatea): Clavoplites haranti sp. n. and Enchelys terrenum (Foissner, 1984) comb. n., and taxonomy of the family Enchelyidae Ehrenberg, 1838

The morphology and infraciliature of two soil haptorid ciliates, Clavoplites haranti sp. n. and Enchelys terrenum (Foissner, 1984) comb. n., collected from Malé Karpaty Mts. and Biele Karpaty Mts. (Slovakia), were investigated using live observation and protargol impregnation. Clavoplites haranti is distinguished from its congeners by a combination of characters including: theronts spatulate to slenderly fusiform, trophonts bursiform, size about 60 x 25 microm in vivo; massive oral bulge with broadly clavate to lemon-shaped, 1.5-2 microm long extrusomes arranged in a ring in oral bulge; ellipsoidal macronucleus and one globular micronucleus; on average 13 ciliary rows, 3 anteriorly differentiated to an inconspicuous dorsal brush. Enchelys terrenum is about 85 x 30 microm in size and differs from its congeners by a combination of characters including spatulate shape; massive oral bulge with 4-6 microm long, fusiform extrusomes arranged in a ring in oral bulge; ellipsoidal to reniform macronucleus and one globular micronucleus; usually 19 ciliary rows, 3 anteriorly differentiated to an ordinary dorsal brush. The diagnoses of the family Enchelyidae and the genus Enchelys are improved. The new genus Armatoenchelys differs from the genera Enchelys and Apoenchelys in having both body and oral bulge extrusomes. Enchelys geleii, E. longitricha, and E. vermiformis are transferred to the new genus.     

红色伪角毛虫的形态学重描述及与相近种的比较(纤毛门,腹毛目)

利用活体观察、蛋白银染色技术对1种海水腹毛目纤毛虫-红色伪角毛虫Pseudokeronopsis rubra的青岛种群之活体形态和纤毛图式做了研究.其特征如下:虫体呈长带状,尾钝圆,身体柔软,高度可曲;皮层颗粒棕黄色,主要呈玫瑰花形分布,其余散布;表膜下具另1种无色、双面凹形颗粒.口围带小膜数为48～55;左、右缘棘毛各1列,中腹棘毛排成典型的锯齿状并延伸至横棘毛附近;额棘毛无明确分化,呈冠状排布并与中腹棘毛列相连续;口棘毛1根,额前棘毛2根;背触毛4列.大核90～140枚.伸缩泡位于体后左侧1/3处.经比较表明,尽管纤毛图式高度相似,P.rubra仍可以很容易地依据体色、伸缩泡的位置、皮层颗粒的大小、颜色、排布等活体特征与相近种区分.说明活体观察在纤毛虫种类鉴定中具有十分重要的作用.     

Morphological redescriptions of four marine ciliates (Ciliophora: Cyrtophorida: Dysteriidae) from Qingdao, China

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.     

Two vicariant Semispathidium species from tropical Africa and central Europe: S. fraterculum nov. spec. and S. pulchrum nov. spec. (Ciliophora,Haptorida)

Using standard methods, we describe two new Semispathidium species from semiterrestrial habitats of tropical Africa and central Europe. Semispathidium fraterculum nov. spec. and S. pulchrum nov. spec. differ from each other and from two Namibian (Southwest African) congeners by body size, the shape and location of the extrusomes; the shape of the macronucleus, the number of ciliary rows, the number of cilia within the rows, and the number of dikinetids comprising the dorsal brush rows. The globular resting cyst of S. fraterculum is unique in having countless granules on the inside of the external layer, forming sharp-angled rows. The distribution of these and two further, not yet described south African species indicates that the genus Semispathidium evolved in subtropical Africa. Semispathidium fraterculum and S. pulchrum are highly similar, both morphologically and ecologically, differing in mainly one important feature: the shape and location of the extrusomes used for prey capture. This suggests that they evolved from a common ancestor whose areal was divided by a vicariant event, causing an independent evolution of the split populations. We argue that this and other species pairs indicate that the vicariance speciation model is applicable to protists.     

Typification of the genus Dileptus Dujardin, 1841 (Ciliophora,Rhynchostomatia)

In their monograph of the dileptids, Vďačný and Foissner (2012) could not clarify the type species of the genus Dileptus Dujardin, 1841. Thus, they suggested that the problem be referred to the International Commission on Zoological Nomenclature. However, recently we discovered that Dujardin (1841) has originally typified Dileptus with Amphileptus anser sensu Ehrenberg (1838) which is in fact a misidentified Amphileptus margaritifer Ehrenberg, 1833, a common species also originally classified in Dileptus. Under Article 70.3.2 of the Code, Dileptus margaritifer (Ehrenberg, 1833) Dujardin, 1841, thoroughly redescribed by Foissner et al. (1995), is now the type of Dileptus. This has the great advantages of historical continuity and that new combinations (names) are not required.     

Food capture and adhesion by the heliozoonActinophrys sol

Summary The heliozoonActinophrys sol is characterized by needle-like axopodia radiating from the spherical cell body. When helio-zoons capture food organisms, the prey is caught by adhesion to the surface of axopodia where numerous extrusomes are present close to the plasma membrane. To understand the molecular mechanism by which the heliozoons capture prey organisms, crude isolation and characterization of the adhesive substance was carried out. Prey flagellates (Chlorogonium elongatum) adhered and aggregated to remnants of heliozoon cells which had been killed by freezing or treatment at high temperature (80 °C for 10 min). Isolated extrusomes, which were prepared as the supernatant of cells homogenized and centrifuged after freezing and thawing, showed strong adhesion to the prey flagellates which responded to the supernatant by adhering their flagella and cell bodies to each other to form bouquet-like cell clusters. The adhesive substance was further extracted from heat-treatedA. sol. This fraction contained filamentous material similar to the secreted contents of the extrusomes observed during feeding. Its adhesive activity was not inhibited by trypsin treatment.     

A new species of Heterosentis Van Cleave, 1931 (Acanthocephala, Arhythmacanthidae), a parasite of pinguipedid fishes in the southwest Atlantic

A new species of arhythmacanthid acanthocephalan, Heterosentis martini n. sp., parasitic in the Argentinean sandperch Pseudopercis semifasciata (Cuvier) (Perciformes, Pinguipedidae) from the coasts of Argentina is described. Heterosentis martini n. sp. differs from all congeneric species by having 10 longitudinal rows of hooks in the proboscis, each with 7-8 hooks, consisting of 1 medium apical and 3 larger sub-apical hooks with root, and 3-4 smaller, basal, curved hooks with rudimentary roots and spines in both ventral and dorsal regions of the body. The most similar species, Heterosentis heteracanthus (Linstow, 1896) Van Cleave, 1931, and Heterosentis brasiliensis Vieira, Felizardo and Luque, 2009, also have 10 longitudinal rows of hooks, but H. heteracanthus differs from the new species by having only 3-5 (more frequently 4) hooks in each row, with only the anterior hook large and bearing a developed root. Heterosentis brasiliensis differs from the new species by possessing 2 sub-apical hooks in each row (instead of 3), similar body length but shorter proboscis, and trunk spines restricted to the ventral surface of body.