Daode Ji

Reconsideration of the Phylogenetic Positions of Five Peritrich Genera, Vorticella, Pseudovorticella, Zoothamnopsis, Zoothamnium, and Epicarchesium (Ciliophora, Peritrichia, Sessilida), Based on Small Subunit rRNA Gene Sequences

ABSTRACT. In order to re‐evaluate the systematics of sessilid peritrich ciliates, small subunit (SSU) rRNA gene sequences were determined for 12 species belonging to five genera: Vorticella, Pseudovorticella, Epicarchesium, Zoothamnium, and Zoothamnopsis. Phylogenetic trees were deduced using Bayesian inference, maximum parsimony, and maximum likelihood methods. The phylogenetic analyses suggest that (1) sessilids which have stalks with continuous myonemes that contract in a zig‐zag fashion form a separate clade from those which have stalks that contract independently and in a spiral fashion, supporting the separation of the family Zoothamniidae from the family Vorticellidae and (2) Epicarchesium and Pseudovorticella, both of which have reticulate silverline systems, are more closely related to each other than to other vorticellids, suggesting that differences in the silverline system (i.e. transverse vs. reticulate) may be the result of genuine evolutionary divergence among sessilid peritrichs. However, the newly sequenced Zoothamnopsis sinica, which has a reticulate silverline pattern, nests within the unresolved Zoothamnium species that have transverse silverline patterns. Thus, there were at least two evolutions of the reticulate silverline pattern character state from a plesiomorphic transverse state in the peritrichid ciliates. The molecular work demonstrates the genus Zoothamnium to be paraphyletic in relation to morphological studies, and suggests that Astylozoon, Opisthonecta, and Vorticella microstoma possibly share a SSU rRNA secondary structure in the helix E10‐1 region.

Morphology and small subunit (SSU) rRNA gene sequence of the new brackish water ciliate Neobakuella flava n. g., n. sp. (Ciliophora, Spirotricha, Bakuellidae) and SSU rRNA gene sequences of six additional hypotrichs from Korea.

ABSTRACT. The morphology and the small subunit (SSU) rRNA gene sequence of the hypotrich Neobakuella flava n. g., n. sp. from the estuary of the Taehwagang River (Ulsan, South Korea) were investigated. The three frontal cirri, the composition of the midventral complex of cirral pairs and rows, and the simple dorsal kinety pattern of three bipolar kineties assign it to the urostyloid taxon Bakuellidae. The increased number of buccal and parabuccal cirri, the presence of transverse cirri, and more than one left marginal row, as well as the lack of caudal cirri separate Neobakuella n. g. from the other bakuellids. Neobakuella flava n. sp. has many 0.3 μm sized green and/or yellow usually dark‐green cortical granules and some sparsely distributed, 2 × 1 μm sized grass green with yellowish shimmer granules. The gene sequence data indicate a close relationship with Diaxonella and a distinct separation from the bakuellid Metaurostylopsis and parabirojimid Parabirojimia. The SSU rRNA gene sequences of four further urostyloids (i.e. Diaxonella pseudorubra, Anteholosticha monilata, Metaurostylopsis struederkypkeae, Pseudourostyla cristata) and two stylonychines (i.e. Sterkiella cavicola, Sterkiella histriomuscorum) from Korea were analyzed. Anteholosticha monilata, type of the genus, is clearly separated from the Holosticha clade, supporting the morphological separation from Holosticha. Sterkiella cavicola, type of Sterkiella, clusters within the stylonychines and is obviously closely related with S. histriomuscorum.

Taxonomic Characterization of Two Marine Peritrichous Ciliates, Pseudovorticella clampi n. sp. and Zoothamnium pararbuscula n. sp. (Ciliophora: Peritrichia), from North China

Abstract. The morphology, infraciliature, and silverline system of two new peritrichous ciliates, Pseudovorticella clampi n. sp. and Zoothamnium pararbuscula n. sp., have been investigated based on both living and silver‐impregnated specimens. Partial sequence of 18S‐ITS1‐5.8S rDNA of Z. pararbuscula is also determined in order to compare it with the closely related congener, Zoothamnium arbuscula. Zoothamnium pararbuscula can be distinguished from its close form Z. arbuscula by the different habitats, the appearance of the main stalk, the position of the contractile vacuole, and the information derived from 18S‐ITS1‐5.8S rDNA sequence analysis. Pseudovorticella clampi n. sp. is distinguished from its congeners by its body shape and size, pellicle granules, habitat, and number of transverse silverlines.

New Contributions to Two Heterotrichous Ciliates, Folliculina simplex (), Condylostoma curva and One Licnophorid, Licnophora lyngbycola (Protozoa, Ciliophora): Descriptions of Morphology and InfraciliatureDons, 1917Burkovsky, 1970Fauré-Fremiet, 1937

Abstract The living morphology and infraciliature of two heterotrichous and one licnophorid ciliates from the north China seas, i.e. Folliculina simplex (Dons 1917), Condylostoma curva Burkovsky, 1970, and Licnophora lyngbycola Fauré-Fremiet, 1937, were investigated using protargol impregnation and in vivo observations. Updated diagnoses and redescriptions of each species are provided. The improved diagnosis of Folliculina simplex is as follows: blue-greyish to blue-greenish Folliculina with broad and unequal-sized peristomial lobes; adoral zone of membranelles comprises about 400 membranelles and forms two-and-half turns within buccal cavity; paroral membrane extends entire length of adoral zone of membranelles; about 50 somatic kineties in mid-body; single ovoid to ellipsoid macronucleus and several micronuclei; lorica vase-shaped, about 150–250 μm long, often with jelly-like covering and inconspicuous neck; marine habitat. Improved diagnosis for Licnophora lyngbycola: marine Licnophora with cup-shaped body and glabrous adhesive disc with which the organism attaches to the filaments of the colourless cyanobacterium Lyngbya; in vivo 80–130 μm long; about 140 adoral membranelles, one micronucleus and a single C-shaped, moniliform macronucleus consisting of about 14 nodules; two specialized dorsal kineties; five peripheral rings on adhesive disc, the 2nd, 3rd, and 5th (outermost) which are incomplete. Based on the Qingdao population, an improved diagnosis for Condylostoma curva is supplied: yellow-brownish Condylostoma with oval to elongated body shape; about 150–350 μm long in vivo; about 68–108 membranelles in adoral zone of membranelles, 4–8 frontal cirri, 22–32 somatic kineties; macronucleus moniliform with 5–13 nodules; with cortical granules; marine habitat.

New contributions to two heterotrichous ciliates, Folliculina simplex (Dons, 1917), Condylostoma curva Burkovsky, 1970 and one licnophorid, Licnophora lyngbycola Fauré-Fremiet, 1937 (Protozoa, Ciliophora): descriptions of morphology and infraciliature.

Abstract The living morphology and infraciliature of two heterotrichous and one licnophorid ciliates from the north China seas, i.e. Folliculina simplex (Dons 1917), Condylostoma curva Burkovsky, 1970, and Licnophora lyngbycola Fauré-Fremiet, 1937, were investigated using protargol impregnation and in vivo observations. Updated diagnoses and redescriptions of each species are provided. The improved diagnosis of Folliculina simplex is as follows: blue-greyish to blue-greenish Folliculina with broad and unequal-sized peristomial lobes; adoral zone of membranelles comprises about 400 membranelles and forms two-and-half turns within buccal cavity; paroral membrane extends entire length of adoral zone of membranelles; about 50 somatic kineties in mid-body; single ovoid to ellipsoid macronucleus and several micronuclei; lorica vase-shaped, about 150–250 μm long, often with jelly-like covering and inconspicuous neck; marine habitat. Improved diagnosis for Licnophora lyngbycola: marine Licnophora with cup-shaped body and glabrous adhesive disc with which the organism attaches to the filaments of the colourless cyanobacterium Lyngbya; in vivo 80–130 μm long; about 140 adoral membranelles, one micronucleus and a single C-shaped, moniliform macronucleus consisting of about 14 nodules; two specialized dorsal kineties; five peripheral rings on adhesive disc, the 2nd, 3rd, and 5th (outermost) which are incomplete. Based on the Qingdao population, an improved diagnosis for Condylostoma curva is supplied: yellow-brownish Condylostoma with oval to elongated body shape; about 150–350 μm long in vivo; about 68–108 membranelles in adoral zone of membranelles, 4–8 frontal cirri, 22–32 somatic kineties; macronucleus moniliform with 5–13 nodules; with cortical granules; marine habitat.

Description of a Marine Peritrichous Ciliate, Pseudovorticella sinensis n. sp. (Ciliophora, Peritrichia) from China

Abstract 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 × 35–45 μm 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 μm long × 5–6 μm wide. The spasmoneme has one row of conspicuous thecoplasmic granules, which are about 0.8 μm in diameter.

Two New Species of Zoothamnium (Ciliophora, Peritrichia) from Korea, with New Observations of Z. parahentscheli Sun et al., 2009

Three peritrichous ciliates, Zoothamnium arcuatum n. sp., Z. grossi n. sp., and Z. parahentscheli Sun et al., 2009, were collected from an estuary of the Taehwagang River, Korea. All these species were investigated based on live observations and silver staining, and their small subunit (SSU) rRNA gene was also sequenced. Zoothamnium arcuatum can be identified by a goblet‐shaped colony, double‐layered peristomial lip, and abstomally shortened row 3 of infundibular polykinety 3 (P3). Zoothamnium grossi is morphologically characterized by an alternately branched stalk with the lowest secondary stalk diverging from the main part of colony, asymmetrically bell‐shaped zooids, and three short, parallel ciliary rows in P3. Phylogenetic analysis revealed that the three Zoothamnium species described in this paper clustered with other members of the family Zoothamniidae, as expected.

Studies on an endoparasitic ciliate Boveria labialis (Protozoa: Ciliophora) from the sea cucumber, Apostichopus japonicus

The morphology and infraciliature of an endoparasitic ciliate, Boveria labialis, isolated from respiratory trees of the sea cucumber, Apostichopus japonicus, were investigated using living observation and silver impregnation methods. Based on the present and previous studies, an improved diagnosis is supplied: marine Boveria, size in vivo about 30-100×15-30 μm, body slender and flask-shaped, with a protruding lobe measuring 5-15 μm in length; one ovoid macronucleus and one micronucleus; single contractile vacuole positioned in posterior 1/4 of body length; 17-26 somatic kinetics; paroral membrane and membranelle 2 forming a double anticlockwise spiral of nearly two turns.

Morphology and Morphogenesis of a Freshwater Ciliate, Epistylis chlorelligerum Shen, 1980 (Ciliophora, Peritrichia)

ABSTRACT. An oligohalobic peritrichous ciliate, Epistylis chlorelligerum Shen, 1980, was collected from a ditch in Hangzhou, China. The morphology, oral infraciliature, and morphogenesis of the species were studied using living and protargol‐impregnated specimens. Zooids of E. chlorelligerum are 160–230 × 50–60 μm in vivo, and characterized by green‐colored endoplasm containing symbiotic algae. The oral infraciliature presents a well‐developed filamentous reticulum linked to the circular fiber of the cytostome; the outer two rows of P3 extend adstomally over P1 and usually enfold it. During binary fission, one daughter cell inherits most part of the old buccal apparatus and the reorganized haplokinety and germinal kinety (Hk′ and G′), and new buccal apparatus of the other daughter cell is mostly developed from the original germinal kinety (G) and haplokinety (Hk): new peniculi 2, 3 (2P2, 2P3), new haplokinety (2Hk), and new germinal kinety (2G) are formed from G, while the new peniculus 1 (2P1) and its peristomial extention (2Pk) originate from Hk. The epistomial membrane can be observed until the two sets of buccal apparatus begin to separate from each other.

Redescription of Pseudovorticella cylindrica (Dons, 1915) nov. comb. and Zoothamnium hiketes Precht, 1935, two poorly defined marine peritrichs (Ciliophora: Peritrichia) from the north China Sea

The living morphology, silverline system and infraciliature of two marine peritrichous ciliates, Pseudovorticella cylindrica (Dons, 1915) nov. comb. (formerly Vorticella cylindrica) and Zoothamnium hiketes Precht, 1935, collected in Qingdao, China, were investigated. Based on the Qingdao populations, both species are redefined. Pseudovorticella cylindrica is characterized by: cell inverted bell‐shaped, about 45×50 µm in vivo; macronucleus J‐shaped; one apically positioned contractile vacuole; pellicle smooth with inconspicuous, closely spaced striations; the number of transverse silverlines from peristome to aboral ciliary wreath 33–40, from aboral ciliary wreath to scopula 14–19; the inner row of peniculus 3 conspicuously short. An updated and supplementary description of Zoothamnium hiketes is also supplied: size of zooid in vivo 70×35 µm on average, elongate in shape with inconspicuously double‐layered peristomial lip; macronucleus C‐formed; one large contractile vacuole apically located; colony dichotomously branched; the number of striations from peristome to aboral ciliary wreath 89–109, from aboral ciliary wreath to scopula 35–43; rows in peniculus 3 parallel to each other.