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The interactions between symbiotic bacterial consortia and their protist hosts in benthic environments have attracted increasing interest in recent years. In the present study, we investigated the diversity of potentially associated bacteria for an astomatous ciliate, Kentrophoros flavus, collected in the intertidal zone of Yantai, China. For the first time, the diversity of the associated bacteria in the species K. flavus was examined using 16S rRNA-based techniques (clone libraries and PacBio sequencing) and the fluorescence in situ hybridization (FISH) technique. The 16S rRNA-based sequencing revealed a higher diversity of associated bacteria in K. flavus than previously expected. In addition to a genus-typical thiotrophic symbiont, the “Candidatus Kentron” stain YE, we provide evidence showing the consistent existence of one Muribaculaceae-like bacterium that was secondarily abundant among the bacterial operational taxonomic units (OTUs). Fluorescence in situ hybridization (FISH) with three specific probes and double-label FISH experiments with “Candidatus Kentron” probes showed that the Muribaculaceae-like bacterium was abundant and merged with the “Candidatus Kentron” stain YE on the cell surface of the host. A phylogenetic analysis of the bacterial 16S rRNA gene showed that the bacterium was a distinct branch in Muribaculaceae, members of which are primarily reported from gut microbiome. The name “Muribaculaceae-like bacterium associated with Kentrophoros flavus” (MLAKF) is proposed for the new bacterium. The higher 16S rRNA diversity in K. flavus and the discovery of MLAKF on the cell surface both suggest a potential bacterial consortium that interacts with the host K. flavus.

Morphology of Cothurnia salina n. sp. (Figs. 1, 2; Table 1) Diagnosis. Body elongated columnar, in vivo 80–98 × 12–19 µm; lorica barrel-shaped, with aboral part heavily thickened; stalk extremely short, with approximately ½ of its length within the lorica; macronucleus wormlike, longitudinally oriented; single contractile vacuole ventrally located; pellicle conspicuously striated, with 62–73 transverse and parallel striations between peristome and aboral trochal band, 32–38 between aboral trochal band and scopula; infundibular polykinety 3 (P3) consisting of two rows of kinetosomes, which are equal in length, parallel to each other and terminate adstomally between P1 and P2. Type location. Muping Salt Factory, Yantai, China (37°25'33.80"N, 121°45'14.20"E). Type material. A slide (registration number 11102201 –01) containing the holotype specimen (protargol preparation, marked by ink circle) and a paratype slide with protargol-stained specimens (registration number 11102201 –02) have been deposited in the Laboratory of Protozoology, Ocean University of China. Etymology. The specific epithet salina refers to the special hypersaline habitat of the new species. Description. Solitary, with slender, cylindroid cell body measuring 80–98 × 12–19 µm (Fig. 1 A, 2A, D, E); body widest at the peristomial lip and not constricted below it (Fig. 1 A, 2A, E). Peristomial lip lacks medial infolding and measures 21–27 µm in diameter. Pellicular striae visible above ×400 magnification (Fig. 2 E), with 62–73 striations from peristome to aboral trochal band and 32–38 from aboral trochal band to scopula (Table 1). Cytoplasm colorless or slightly grayish, usually containing several food vacuoles (diameter 5–10 µm) located in center of body. Single contractile vacuole located adorally, beneath peristomial lip and near ventral wall of infundibulum (Fig. 1 A, 2D). Macronucleus slender, cylindroid, longitudinally oriented (Fig. 1 A, 2F, G); micronucleus not observed. Lorica colorless, transparent, truncate pyriform, measuring 62–74 × 30–35 µm and aperture diameter of 21–30 µm. Aboral part of lorica thickened; wall 3 µm thick. Stalk 10 µm long, with approximately ½ of length exterior to lorica wall. Oral infraciliature as shown in Fig. 1 E, 2H. Haplokinety and polykinety make approximately one and one-half circuits together around peristome before entering infundibulum. Haplokinety and polykinety parallel to one another on peristome, diverging within infundibulum to lie on opposite walls (Fig. 1 E). Three infundibular polykineties (P1–3), with P1 and P2 consisting of three rows of kinetosomes and P3 of two rows. Adstomal ends of rows in P1 terminate at different levels, with inner row slightly shortened; P2 terminates adstomally above adstomal ends of P1 and P3, with row 3 not merging with P1 abstomally and significantly divergent from other two rows abstomally (Fig. 1 E). Rows of P3 parallel and equal in length, terminating adstomally at point approximately midway between adstomal ends of P2 and P1 (Fig. 1 E). Germinal kinety runs parallel to haplokinety in abstomal half of infundibulum (Fig. 1 E). Aboral trochal band consisting of series of dikinetids encircling cell at point 2/3 of distance from peristome to scopula (Fig. 2 E). Phylogenetic analysis based on SSU rRNA sequences (Fig. 3). The SSU rRNA gene sequence of Cothurnia salina (GenBank accession number KT956998) is 1,629 bp long and has a GC content of 43.09%. The sequence of C. salina differs from that of C. annulata (KU363275) by 38 nucleotides (sequence identity 97.4%); C. sp. 0 924 (KU363268) by 69 nucleotides (sequence identity 95.2%). Topologies of BI and ML trees were basically congruent, and thus, only the topology of the BI tree is presented in Fig. 3, with support values from both analyses indicated on branches. In both BI and ML trees, C. salina n. sp. clustered in the family Vaginicolidae as expected. C. salina n. sp. clustered with C. annulata with full support (1.00 BI, 100% ML) and these two species are sisters to the species C. sp. 0 924 with moderate support (0.80 BI, 57% ML). All data based on specimens in vivo. Abbreviations: Min, minimum; Max, maximum; Mean, arithmetic mean; SD, standard deviation; CV, coefficient of variation (%); n, number of individuals investigated.

Zhang, Xiumei, Ji, Daode, Zhang, Qianqian, Li, Chenghua (2015): Description and phylogeny of a new prostomatid, Metacystis similis nov. spec. (Protista, Ciliophora) from the East China Sea. Zootaxa 4033 (4): 584-592, DOI: http://dx.doi.org/10.11646/zootaxa.4033.4.8

Morphology of Metacystis similis nov. spec. (Figs. 1, 2; Table 1) Diagnosis. Cylindrical marine Metacystis with a slightly blunt anterior end, in vivo 50- 70 x 18-23 ��m; cell not loricate, uniformly cinctured by 16���18 transverse rings of cilia, which are arranged into 32���36 longitudinal somatic kineties; the oral apparatus consisting of one circumoral kinety of dikinetids and six girdles of monokinetids that pack together; one spherical macronucleus located in the center of the body; the caudal cilium possessed one hemicycle transparent and protruding terminal vacuole. Type of material. A protargol slide with the holotype specimen was deposited in the collection of Laboratory of Protozoology, Ocean University of China, with registration number 20141107 Z. The holotype specimen is marked by an ink circle on the coverslip. A paratype slide with protargol-impregnated specimens was deposited in the Laboratory of Protozoology, Yantai University, China with registration number 20141108 Z. Etymology. The Latin adjective " similis " denotes general similarity between the new species and its congeners. Description. Cells are 50��� 70 x 18���23 ��m in vivo, and the body shape is slightly changeable with mostly barrel-shaped or cylindrically-shaped (Figs. 2 A���C). Body is rarely contractile, and the ratio of length: width is ca. 2.5���3: 1 (Table 1). From the blunt posterior end, the body slightly tapers toward the truncated anterior aperture (Figs. 2 A���C). Lorica is absent. The cytoplasm is colorless to slightly grayish and contains many large granules (5���8 ��m in diameter) but is transparent posteriorly, which is due to the existence of a large caudal vacuole (15���18 ��m in diameter) (Figs. 2 B��� E). The pellicle is rigid, and its surface consists of transverse ridges (Figs. 1 A, 2 G, arrowheads) and longitudinal somatic kineties, thus clear rectangular meshes can be observed above 100 �� magnification (Figs. 1 J, 2 F). The macronucleus is large and round to oval, mostly centrally located, in vivo always exhibits a transparent area. After impregnation, several nucleoli were scattered in the macronucleus. A large hemicycle transparent vacuole protrudes at the terminal end of the cell (Figs. 2 A���D). Cilia of Metacystis similis nov. spec. are densely arranged with a length of ca. 9 ��m at the oral part and a length of 6 ��m in somatic kineties. Caudal cilia are absent. Metacystis similis nov. spec. always utilizes a single mode of locomotion: when swimming, the body moves forward at moderate speed and rotates along its longitudinal axis. The cell is not sensitive to disturbance or stimulation. When observed under microscope, the cell constantly moves back and forth without pause at the bottom of the water. The circumoral ciliature is composed of one circumoral dikinety and six densely packed girdles of monokinetids (Fig. 2 I), which has clear circumscription with somatic ciliature. Additionally, the oral infraciliature is considerably denser than the somatic counterparts. The somatic infraciliature is composed of 32���36 longitudinal kineties extending over the entire length of body and patterned as 16���18 transverse rows of monokinetids (Fig. 2 H). Abbreviations: CV, coefficient of variation (%); Max, maximum; Mean, arithmetic mean; Min, minimum; n, number of individuals investigated; SD, standard deviation; SE, standard error of arithmetic mean., Published as part of Zhang, Xiumei, Ji, Daode, Zhang, Qianqian & Li, Chenghua, 2015, Description and phylogeny of a new prostomatid, Metacystis similis nov. spec. (Protista, Ciliophora) from the East China Sea, pp. 584-592 in Zootaxa 4033 (4) on pages 585-586, DOI: 10.11646/zootaxa.4033.4.8, http://zenodo.org/record/238140

Zoothamnium nii Ji et al., 2005 (Fig. 2; Table 1) Emended diagnosis. Marine Zoothamnium with colony up to 1 mm high; moderately elongate, median primary stalk giving rise to secondary stalks in regular alternate series in single plane,. Zooids elongate, vase-shaped, measuring 70–80 × 40–50 µm in vivo. Peristomial lip extremely thick, with medial, circumferential infolding in peristomial lip when expanded (“double-layered”). Macronucleus C-shaped, transversely oriented, located in oral half of cell. Pellicular striations indistinct at lower magnifications; 45–60 silverlines lying between peristomial lip and trochal band and 20–30 between trochal band and scopula. P 3 consists of three rows that are equal in length and parallel to each other, row 1 slightly separated from rows 2 and 3 for most of length, but all three rows converging adstomally. Redescription. Colony moderately large, up to 1 mm high and containing 30–50 zooids, with broad, diamondshaped outline. Secondary stalks up to 500 µm long, branching off primary stalk in regular alternate series. Basal secondary stalks longest, with stalks decreasing progressively in length toward tip of colony; secondary stalks branching to form short, dichotomous tertiary branches bearing 2 zooids or single tertiary branches (Figs. 2 E, J, K). Stalk with smooth surface and diameter of 12 µm in basal portion of primary stalk, narrowing to 9 µm at distal ends of tertiary stalks. Spasmoneme with diameter of 3.5 µm in primary stalk and 2.5 µm at distal ends of tertiary stalks; band of mitochondria visible as dark granules measuring 0.5 × 0.8 µm, winding along helical path just beneath surface of spasmoneme. Zooids elongate, bell-shaped, measuring 70–80 × 40–50 µm (n= 12) (Figs. 2 A, I, L, O, P). Body deeply constricted below peristomial lip, which is indented by prominent, medial, circumferential infolding (“double-layered”). Maximum width of cell usually at peristomial lip, but occasionally in oral third of body as well; epistomial disc moderately elevated above peristomial lip (Figs. 2 A, I, O, P). Pellicular striations easily detectable above × 400 magnification (Figs. 2 O, P), but surface of body appears completely smooth at low magnifications (Fig. 2 L). Telotroch discoid, measuring 55–65 µm x 40 µm (Fig. 2 R). Cytoplasm of zooids colorless or slightly gray, filled with tiny (0.5 µm diameter), dense granules and usually containing a few large (5–10 µm in diameter), transparent or gray food vacuoles typically located in center of body (Figs. 2 A, L). Single contractile vacuole in adoral position beneath epistomial lip and near dorsal wall of infundibulum. Macronucleus C-shaped, transversely oriented, surrounding micronucleus and lower half of infundibulum (Figs. 2 A, M, N). Oral infraciliature as shown in Figures 2 B, H, N. Haplo- and polykinety making one and one-quarter circuits around peristome and one additional circuit within infundibulum. Haplokinety and polykinety parallel on peristome, diverging within infundibulum to lie on opposite walls (Fig. 2 H). Epistomial membrane short, located at entrance into infundibulum (Fig. 2 H, arrow). Germinal kinety running parallel to haplokinety in adoral half of infundibulum (Fig. 2 N, arrow). Each of three infundibular polykineties consisting of three rows of kinetosomes. All rows of Pl terminating adstomally at level of cytostome; rows of P 2 terminating adstomally at adstomal curvature of P 1. Rows of P 2 terminating abstomally without merging with P 1; abstomal 1 / 4 of row 3 of P 2 diverging from other rows of P 2 (Figs. 2 B, H).. All rows of P 3 terminating adstomally at point slightly beyond adstomal end of P 2 and abstomally at point approximately 1 / 3 of distance from adstomal to abstomal end of P 2. Row 1 of P 3 converging with other tow reasons near adstomal end, separated slightly from rows 2 and 3 along remainder of length (Fig. 2 B). Trochal band consisting of band of dikinetids encircling cell at point 2 / 3 of distance from peristome to scopula (Fig. 4 H, arrows). Silverline system consisting of closely spaced, parallel, transverse silverlines (Fig. 2 Q); 45–60 silverlines present between peristome and trochal band, 20–30 between trochal band and scopula. Silverlines near peristome spaced farther apart than those around scopula, and pellicular pores sparsely distributed alongside silverlines (Fig. 2 Q). Remarks: In general, zooids of alternately branched species of Zoothamnium such as Z. alternans, Z. niveum and Z. plumula, lack a medial, circumferential infolding on the peristomial lip (“single-layered”), and zooids with an infolding around the peristomial lip (“double-layered”) are more typical of dichotomously branched species such as Z. duplicatum, Z. mucedo, and Z. maximum (Bauer-Nebelsick et al. 1996; Ji & Song 2004; Ji et al. 2005 a, 2006 b). Therefore, Z. nii has an unusual complex of characters (i.e. the alternately branched stalk and the infolded peristomial lip of the zooid), by which it can be distinguished easily from all the congeners mentioned above. Another species described very recently, Z. alrasheidi Ji et al., 2009, also possesses this set of characteristics during its early development because its zooids have an infolded peristomial lip and its young colonies are alternately branched. However, a colony of Z. alrasheidi in its early stages of development can be distinguished from Z. nii by its larger zooids (80–120 × 50–60 µm vs. 70–80 × 40–50 µm) and a differing pattern of rows in P 3 of the infundibular infraciliature (rows 2 and 3 combined into a single band and divergent from row 1 vs. all three rows distinct and parallel) (Ji et al. 2009). Kahl (1933, 1935) reported two populations of Zoothamnium with an infolded peristomial lip as Z. duplicatum (Figs. 2 C, D) and Zoothamnium sp. (Figs. 2 F, G) respectively. However, both of them had an alternately branched stalk, which is distinctly different from the dichotomous branching pattern characteristic of Z. duplicatum (Kahl 1933; Ji et al. 2005 a), but very similar to present species. Accordingly, we suggest that both of these Zoothamnium populations described by Kahl be regarded as synonyms of Z. nii.

Anteholosticha pseudomonilata n. sp. (Figs 1���3; Tables 1���3) Diagnosis. Grey coloured Anteholosticha, 110���190 ��m �� 40���80 ��m in vivo; contractile vacuole mid-body positioned; 29���41 adoral membranelles; 1 buccal, 3 frontal, 2 frontoterminal, 2 pretransverse and 8���11 transverse cirri; midventral complex composed of 10���16 pairs of zigzagging midventral cirri, extending posteriorly to slightly ahead of pretransverse cirri; left and right marginal row with about 28 and 29 cirri, respectively; 4 entirely long dorsal kineties; cortical granules colourless and pigment-like, 0.5 ��m across, longitudinally arranged in more or less short rows on whole cortex except along dorsal kineties and cirral rows; 8���12 macronuclear nodules located left of midline. Type locality. Brackish water from the Taehwagang River (35 �� 32 �� 56 "N; 129 �� 20 �� 11 "E) near Ulsan Bay which flows into the East Sea, at Ulsan, South Korea. Type slides. Two permanent slides of protargol-impregnated specimens are deposited as a holotype and a paratype in the collection of National Institute of Biological Resources (NIBR), Incheon, South Korea and Department of Biology, University of Ulsan, Ulsan, South Korea and with registration numbers NIBRPR0000102719 and LLQ- 20091123 -05-02, respectively. Etymology. The species-group name pseudomonilata is a composite of the Greek adjective pseudo- (wrong, lying) and the name of the most similar congener Anteholosticha monilata which resembles our form in having the macronucleus-nodules forming a chain (see details about etymology of monilata in Berger 2006). The ending of the species-group name is defined (fixed) via the genus. Description. Size mostly 110���140 ��m �� 40���60 ��m in vivo. Body shape slightly variable and elliptic-like, anterior portion conspicuously narrowed and forming a slightly cephalized appearance, while rear end broadly rounded; left margin more convex than right part (Figs. 1 A; 2 A, 2 B). Body flexible, only slightly contractile. Dorsoventrally flattened about 2: 1. Pellicle thin and soft. Cortical granules colourless and spherical in shape, about 0.5 ��m in diameter, basically arranged in more or less longitudinal short rows on whole cortex except along cirral rows and dorsal kineties with some single ones sparsely distributed throughout the cell surface (Figs. 1 C; 2 C). Food vacuoles difficult to recognize except for many yellowish to brownish light-reflecting crystals scattered within transparent cytoplasm. Two groups of inclusions remarkably recognized, which are globular and concave like, respectively, 2���5 ��m in diameter, consistently situated and give rise to darker colour in both ends of the cell (Figs. 1 A, 1 B; 2 E). 8���12 colourless macronuclear nodules globular to ellipsoidal shaped, serially distributed in mid-portion of body left of midline which can be easily observed under middle to high magnification in vivo; individual nodules, in impregnated specimens, 8���20 ��m�� 8���18 ��m, containing small nucleoli (Figs. 1 E; 2 D, 2 F). Usually two micronuclei ovoid in shape located separately among the macronuclei, 5���10 ��m �� 3���8 ��m across after fixation (Figs. 1 E; 2 D, G). Single contractile vacuole positioned in mid-body near left margin with two long collecting canals (Fig. 1 A). Locomotion relatively slow, but crawling without pause. Body apparently flexible, folded or twisted when crawling on bottom of Petri dish or drilling through debris. Adoral zone of membranelles occupied 30.3���41.7 % of body length in fixed specimens (Table 1), base of longest membranelles about 9 ��m long. Distal end of AZM terminated at right margin of cell and bending posteriad at about anterior 1 / 3 of buccal field (Figs. 1 D; 2 F). Paroral and endoral membrane almost the same length, likely both composed of monokinetids, distinctly intersecting each other and terminating anteriorly at about 2 / 5 of buccal field (Figs. 1 D; 2 H). Single buccal cirrus situated near the intersection of undulating membranes (Figs. 1 D; 2 H). Three slightly enlarged frontal cirri lying in anterior frontal area with right one very close to the distal end of adoral zone of membranelles (Fig. 2 H). Consistently two frontoterminal cirri near and right to the distal end of adoral zone of membranelles (Fig. 2 H). 8���11 relatively undeveloped transverse cirri arranged in J-shaped row, ca. 15 ��m long in vivo, slightly protruding beyond rear end of cell (Figs. 1 A, 1 D; 2 G). Always two pretransverse ventral cirri located close to the right transverse cirrus (Fig. 1 D). Midventral complex composed of 10���16 pairs of midventral cirri arranged in a typical zig-zag pattern, continuing with frontal cirri and terminated ahead of the level of the left-most transverse cirrus (Figs. 1 D; 2 F, 2 G). The last midventral cirri often dispersedly situated other than in a zigzagging pattern (Fig. 1 D). Two marginal rows distinctly separated posteriorly ahead of cell end, the cirri within which about 10 ��m long and never protruding the margins in life; 23���33 cirri in left row, while 24���34 in right one (Figs. 1 A, 1 D; 2 A, 2 F). Invariably four complete dorsal kineties with dorsal cilia about 3 ��m long. Usually two ���extra��� dorsal bristles present on the anterior right margin of the body (Figs. 1 E; 2 C). Abbreviations: CV = coefficient of variation in %, Max = maximum, Mean = arithmetic mean, Median = median value, Min = minimum, n = number of individuals examined, SD = standard deviation, SE = standard error of arithmetic mean. Comparison. Currently, over 40 morphotypes have been included in the genus Anteholosticha, most of which need further studies and redescription (Berger 2006). As one of the most significant criteria for species circumscription, nuclear apparatus (number, arrangement) usually can be easily detected and described even in the cursory data, furthermore, the diversity of which is quite high in Anteholosticha, therefore the congeners resemble our form in having a series of macronuclear nodules should be compared here. Morphologically, the most similar congener Anteholosticha monilata (Kahl, 1928) Berger, 2003 (type species) resembles A. pseudomonilata n. sp. in several features (e.g. body shape, contractile vacuole, ciliary arrangement, the number of membranelles and transverse cirri), however, differs from the latter in having 6 or more dorsal kineties (vs. 4), 19���27 midventral pairs (vs. 10���16), 4���23 macronuclear nodules (vs. 8���12), extrusomes (vs. absent), and no cortical granules (vs. present) thus both forms can be distinctly separated (e. g. Augustin & Foissner 1992; Berger 2006). Likewise, other similar Anteholosticha spp., namely, A. distyla (Buitkamp, 1977) Berger, 2003, A. xanthichroma (Wirnsberger & Foissner, 1987) Berger, 2003, A. australis (Blatterer & Foissner, 1988) Berger, 2003, A. mancoidea (Hemberger, 1985) Berger, 2003, A. randani (Groli��re, 1975) Berger, 2003, A. sphagni (Groli��re, 1975) Berger, 2003, A. sigmoidea (Foissner, 1982) Berger, 2003, and A. extensa (Kahl, 1932) Berger, 2003 can be easily distinguished from A. pseudomonilata n. sp. by a number of features including habitat, body shape, size, the position of the contractile vacuole, cortical granules, and morphometric data (details see Table 2) (Berger 2003, 2006; Blatterer & Foissner 1988; Borror & Wicklow 1983; Buitkamp 1977; Foissner 1982; Groli��re 1975; Hemberger 1985; Kahl 1932; Wirnsberger & Foissner 1987). SSU rRNA gene sequence analysis: The length of the complete SSU rRNA gene sequence of Anteholosticha pseudomonilata n. sp. is 1772 bp; the nucleotide sequence has been given the accession number HM 568416. The GC content is 44.75 %, which is within the range of other ciliates. Among the dataset of 1795 total positions, a total of 244 mismatched nucleotides are revealed from the alignment of six Anteholosticha species (Fig. 3). Of these, 24 positions are unique to A. pseudomonilata. SSU rRNA gene sequence similarity among A. pseudomonilata and the other five species are listed in Table 3. The SSU rRNA gene sequence comparison study clearly exhibits a considerable inconsistency of Anteholosticha pseudomonilata from other five congeners. Pairwise sequence similarities between A. pseudomonilata and its congeners range from 92.38 % to 96.56 % (Table 3). The comparatively high sequence discrepancy (3.44 %) with the most similar morphotype A. monilata strongly suggests our form as a distinct species. Anteholosticha monilata is the type species indicating that the new species is a true member of the genus. By contrast, some other species seem to be not congeneric as indicated by the high differences in the structural similarity (Table 3). This supports the assumption by Berger (2003, 2006) that members of the genus Anteholosticha are likely not to be a monophyletic group. These higher ranges of molecular divergence also coincide with the statement of morphological analysis to establish A. pseudomonilata as an individual species of the genus Anteholosticha. A. pseudomonilata A. monilata A. parawarreni A. scutellum A. multistilata A. monilata 96.56 A. parawarreni 93.07 93.12 A. scutellum 93.11 92.88 97.37 A. multistilata 94.67 94.55 94.09 94.58 A. manca 92.38 93.15 91.32 91.52 93.45, Published as part of Li, Liqiong, Khan, Sadia Nawroz, Ji, Daode & Shin, Mann Kyoon, 2011, Morphology and SSU rRNA gene sequence of the new brackish water ciliate, Anteholosticha pseudomonilata n. sp. (Ciliophora, Hypotrichida, Holostichidae) from Korea, pp. 51-59 in Zootaxa 2739 on pages 52-57, DOI: 10.5281/zenodo.201911, {"references":["Berger, H. (2006) Monograph of the Urostyloidea (Ciliophora, Hypotricha). Monographiae Biologicae, 85, 1 - 1303.","Kahl, A. (1928) Die Infusorien (Ciliata) der Oldesloer Salzwasserstellen. Archiv fur Hydrobiologie, 19, 189 - 246.","Berger, H. (2003) Redefinition of Holosticha Wrzesniowski, 1877 (Ciliophora, Hypotricha). European Journal of Protistology, 39, 373 - 379.","Augustin, H. & Foissner, W. (1992) Morphologie und Okologie einiger Ciliaten (Protozoa: Ciliophora) aus dem Belebtschlamm. Archiv fur Protistenkunde, 141, 243 - 283.","Buitkamp, U. (1977) Die Ciliatenfauna der Savanne von Lamto (Elfenbeinkuste). Acta Protozoologica, 16, 249 - 276.","Wirnsberger, E. & Foissner, W. (1987) Morphologie von Holosticha xanthichroma sp. n. und die Variabilitat der Infraciliatur in der Gattung Holosticha (Ciliophora, Hypotrichida). Acta Protozoologica, 26, 1 - 8.","Blatterer, H. & Foissner, W. (1988) Beitrag zur terricolen Ciliatenfauna (Protozoa: Ciliophora) Australiens. Stapfia, 17, 1 - 84.","Hemberger, H. (1985) Neue Gattungen und Arten hypotricher Ciliaten. Archiv fur Protistenkunde, 130, 397 - 417.","Groliere, C. A. (1975) Descriptions de quelques cilies hypotriches des tourbieres a sphaignes et des etendues d'eau acides. Protistologica, 11, 481 - 498.","Foissner, W. (1982) Okologie und Taxonomie der Hypotrichida (Protozoa: Ciliophora) einiger osterreichischer Boden. Archiv fur Protistenkunde, 126, 19 - 143.","Kahl, A. (1932) Urtiere oder Protozoa I: Wimpertiere oder Ciliata (Infusoria) 3. Spirotricha. Die Tierwelt Deutschlands, 25, 399 - 650.","Borror, A. C. & Wicklow, B. J. (1983) The suborder Urostylina Jankowski (Ciliophora, Hypotrichida): morphology, systematics and identification of species. Acta Protozoologica, 22, 97 - 126."]}

Zoothamnium wangi Ji et al., 2005 (Fig. 3; Table 1) Emended diagnosis. Marine Zoothamnium with colony up to 1 mm high: alternately branched with few (2���4), very long secondary branches. Zooids campanulate to subconical, measuring. 65���90 �� 45���55 ��m in vivo. Peristomial lip thick, without medial, circumferential infolding when expanded. Macronucleus C-shaped, transversely oriented, located in oral half of cell. Pellicular striations closely spaced; 70���85 silverlines lying between peristomial lip and trochal band and 38���50 between trochal band and scopula. P 3 consists of two ciliary rows, with row 2 offset slightly toward cytostome relative to row 1. Redescription. Colony moderately large, up to 1 mm high and containing ca. 100 zooids, with broad, fanshaped outline (Figs. 3 E, 4 A). Secondary stalks branching alternately from primary stalk, with most basal 2���3 secondary stalks growing to the same length as primary stalk (Figs. 3 E, 4 A). Cortex of stalk colorless and transparent, with smooth surface and fine longitudinal striations in interior. Diameter of stalk ranging 20 ��m in primary stalk to 10 ��m in distal branches; spasmoneme measuring 4���10 ��m in diameter, containing densely arranged mitochondria (Fig. 3 J). Zooids campanulate to subconical, 65���90 ��m (n= 4) long, widest at peristomial lip, which measures 45���55 ��m (n= 4) in diameter when fully expanded (Figs. 3 A, G). Peristomial lip thick, without secondary circumferential infolding; epistomial disc moderately elevated above peristomial lip (Figs. 3 A, G). Pellicular striations closely spaced and not prominent, visible only above �� 400 magnification (Fig. 3 H); surface of body appearing uniformly smooth at low magnifications. Cytoplasm transparent and slightly grayish, occasionally containing a few gray or yellowish food vacuoles of uneven size (2���10 ��m) in center of body (Figs. 3 A, 4 B, C). Single contractile vacuole in adoral position beneath epistomial disc and near dorsal wall of infundibulum. Macronucleus C-shaped, transversely oriented, surrounding micronucleus and lower half of infundibulum (Figs. 3 A, I, L). Micronucleus spherical, located adoral to center of macronucleus (Figs. 3 A, I, arrow). Oral infraciliature as shown in Figures 3 D, E, L, M. Haplo- and polykinety making one and one-quarter circuits around peristome and one additional circuit within infundibulum. Epistomial membrane short, located at entrance into infundibulum (Fig. 3 E, arrow). Germinal kinety running parallel to haplokinety in adoral half of infundibulum (Fig. 3 L, arrow). Infundibular polykineties 1 and 2 consisting of three rows of kinetosomes each; P 3 consisting of two rows. All rows of Pl terminating adstomally at level of cytostome; rows of P 2 terminating adstomally at adstomal curvature of P 1. Rows of P 2 terminating abstomally without merging with P 1; abstomal 1 / 4 of row 3 of P 2 diverging from other rows of P 2 (Figs. 3 D, E). Row 2 of P 3 displaced adstomally for short distance relative to row 1 (Fig. 3 D). Trochal band consisting of band of dikinetids encircling cell at point 3 / 4 of distance from peristome to scopula (Fig. 3 L, arrowhead). Silverline system consisting of closely spaced, parallel, transverse silverlines, which are spaced relatively wider apart near peristome (Figs. 3 B, K); 70���85 silverlines present between peristome and trochal band, 38���50 between trochal band and scopula. Pellicular pores staining faintly, numerous, randomly arranged along silverlines. Remarks. Zoothamnium wangi is occasionally found in eutrophic marine waters and can be identified easily by the distinctive branching pattern of the colony, shape and size of zooids, number of silverlines, and the pattern of kinetosome rows in P 3. Zoothamnium plumula, Z. commune, Z. alternans, and Z. xuianum resemble Z. wangi in having an alternately branched stalk and a relatively thin peristomial lip without a medial circumferential infolding. In the present study, it was observed that young colonies of Z. plumula very much resemble mature colonies of Z. wangi in outline as well as shape and size of zooids and, therefore, cannot be distinguished from the latter by characters visible in the living organisms. However, the two species can be distinguished easily in preparations stained with silver nitrate or protargol by the total number of silverlines (108���135 in Z. wangi vs. 72���87 in Z. plumula) and the number of ciliary rows in P 3 (2 in Z. wangi vs. 3 in Z. plumula). Zoothamnium commune resembles Z. wangi in most living characters. However, Z. wangi has more silverlines from the peristomial lip to the trochal band (70���85 vs. 59���70) and a different number of kinetosome rows in P 3 (2 in Z. wangi vs. 3 in Z. commune) (Ji et al. 2006 b). Zoothamnium alternans has large macrozooids that form acetabuliform telotrochs on the primary stalk, which are lacking in Z. wangi, plus its microzooids are considerably smaller than zooids of Z. wangi (40���56 �� 26���32 ��m vs. 65���90 �� 45���55 ��m) (Ji et al. 2006 b). Zoothamnium xuianum has also much smaller zooid size than that of Z. wangi (30���50 �� 20���40 ��m vs. 65���90 �� 45���55 ��m), thus it can be well distinguished from the latter (Sun et al. 2005) Living colonies of two other congeners, Z. thiophilum Stiller, 1946 and Z. hentscheli Kahl, 1935, also resemble Z. wangi, and their infraciliatures and silverline systems remain unknown, preventing a comparison with those of Z. wangi. However, both of these species are freshwater forms (Kahl 1935; Stiller 1946) and Z. wangi seems to be found exclusively in marine habitats., Published as part of Ji, Daode, Shin, Mann Kyoon, Choi, Joong Ki, Clamp, John C., Al-Rasheid, Khaled A. S. & Song, Weibo, 2011, Redescriptions of five species of marine peritrichs, Zoothamnium plumula, Zoothamnium nii, Zoothamnium wang, Pseudovorticella bidulphiae, and Pseudovorticella marina (Protista, Ciliophora), pp. 47-59 in Zootaxa 2930 on pages 53-57, DOI: 10.5281/zenodo.278023, {"references":["Ji, D., Song, W. & Warren, A. (2006 b) Redescriptions of three marine peritrichous ciliates, Zoothamnium alternans Claparede et Lachmann, 1859, Z. sinense Song, 1991 and Z. commune Kahl, 1933 (Ciliophora: Peritrichia), from North China. Acta Protozoologica, 45, 27 - 39.","Stiller, J. (1946) Beitrag zur Kenntnis der Peritrichenfauna der Schwefelthermen von Split. Annales Historico-Naturales Musei Nationalis Hungarici, 39, 19 - 56.","Kahl, A. (1935) Urtiere oder Protozoa I: Wimpertiere oder Ciliata (Infusoria) 4. Peritricha und Chonotricha. Tierwelt Deutschlands, 30, 651 - 886."]}

Ji, Daode, Shin, Mann Kyoon, Choi, Joong Ki, Clamp, John C., Al-Rasheid, Khaled A. S., Song, Weibo (2011): Redescriptions of five species of marine peritrichs, Zoothamnium plumula, Zoothamnium nii, Zoothamnium wang, Pseudovorticella bidulphiae, and Pseudovorticella marina (Protista, Ciliophora). Zootaxa 2930: 47-59, DOI: 10.5281/zenodo.278023

Pseudovorticella bidulphiae (Stiller, 1939) Ji, Sun, Song & Warren, 2009 (Fig. 4; Table 1) Pseudovorticella bidulphiae is characterized by the following characteristics: cell body measuring 30���40 �� 35���40 ��m (n= 4) in vivo, two ventrally located contractile vacuoles, J-shaped macronucleus, 24���28 silverlines lying between peristome and trochal band, 9���11 silverlines lying between trochal band and scopula, P 3 composed of only two ciliary rows with row 1 noticeably shorter than row 2 at its adstomal end (Song et al. 2009). Here, we supply its illustrations of morphology (Fig. 4) and a brief comparison with related species: At low magnifications, Pseudovorticella pseudocampanula Foissner, 1979 (Fig. 4 E), P. sauwaldensis Foissner & Schiffmann, 1979 (Fig. 4 F) and Vorticella venusta Nenninger, 1948 (Fig. 4 G) resemble P. bidulphiae in shape and size of the cell body. However, all three of these species live in fresh water (vs. marine habitat in P. bidulphiae) and a single contractile vacuole (vs. 2 in P. bidulphiae) (Foissner 1979; Foissner & Schiffmann 1979)., Published as part of Ji, Daode, Shin, Mann Kyoon, Choi, Joong Ki, Clamp, John C., Al-Rasheid, Khaled A. S. & Song, Weibo, 2011, Redescriptions of five species of marine peritrichs, Zoothamnium plumula, Zoothamnium nii, Zoothamnium wang, Pseudovorticella bidulphiae, and Pseudovorticella marina (Protista, Ciliophora), pp. 47-59 in Zootaxa 2930 on page 57, DOI: 10.5281/zenodo.278023, {"references":["Foissner, W. & Schiffmann, H. (1979) Morphologie und silberliniensystem von Pseudovorticella sauwaldensis nov. spec. und Scyphidia physarum Lachmann, 1856 (Ciliophora: Peritrichida) Berichte der Naturwissenschaftlich-Medizinischen Vereinigung in Salzburg, 3 - 4, 83 - 94."]}

Pseudovorticella marina (Greeff, 1870) Ji, Sun, Song & Warren, 2009 (Fig. 5; Table 1) Pseudovorticella marina is characterized by the following characteristics: cell body measuring 40–50 × 35–45 µm (n= 8) in vivo, macronucleus J-shaped, single contractile vacuole located near ventral wall of infundibulum, 25–30 transverse silverlines lying between peristome and trochal band, 10–15 silverlines lying between trochal band and scopula, P 3 composed of three ciliary rows, rows 1 and 2 shorter than row 3 at adstomal ends (Song et al. 2009). Illustrations of its morphology (Fig. 5) and brief comparison with similar species are also presented here. The congener that most closely resembles P. marina is P. punctata (Dons, 1918) Warren, 1987 (Fig. 5 E), which has similar body shape and size, but can be separated by its tuberculate pellicle (vs. smooth in P. marina) and P 3 consisting of two rows (vs. 3 rows in P. m a r i n a) (Ji et al. 2006 a). Living cells of,three species of Vorticella, V. campanulata (Kahl, 1933) Šramek-Hušek, 1948 (Fig. 5 F), V. f us ca Precht, 1935 (Fig. 5 G) and V. j a e r a e Precht, 1935 (Fig. 5 H), also bear some resemblance to P. marina at low magnification. Vorticella campanulata and P. m a r i n a have similar numbers of silverlines, but the former is a freshwater species (vs. marine in P. m a r i n a). Vorticella fusca has larger body than P. marina (80–110 × 65–75 µm vs. 40–50 × 35–45 µm), and zooids of V. j a e r a e do not have the elongate and twisted macronucleus and strongly everted peristomial lip characteristic of P. marina (Warren 1986).

Zoothamnium plumula Kahl, 1933 (Fig. 1; Table 1) Emended diagnosis. Marine Zoothamnium with colony up to 3 mm high; elongate, median primary stalk giving rise to secondary stalks in regular alternate series in single plane to create feather-shaped outline. Zooids conical to vase-shaped, measuring 50���75 �� 35���45 ��m in vivo; peristomial lip thick, without medial, circumferential infolding when expanded. Macronucleus C-shaped, transversely oriented, located in oral half of cell. Pellicular striations closely spaced and indistinct at lower magnifications; 50���70 silverlines lying between peristomial lip and trochal band and 20���30 between trochal band and scopula. P 3 consists of three rows of kinetosomes that are equal in length; row 1 separated from rows 2 and 3 by gap in abstomal quarter and all three rows converging adstomally. Redescription. Colony large, up to 3 mm tall and including over 500 zooids. Secondary stalks up to 800 ��m long, branching off elongate primary stalk in regular, alternate series in one plane; tertiary stalks with same pattern of branching, measuring less than 120 ��m in length (Figs. 1 B, D���F, J). Secondary stalks increasing slightly in length from most basal ones to medial region of colony and then decreasing in length toward tip of colony to create feather-shaped outline. Occasionally, most basal secondary stalk more highly developed and considerably longer than other secondary stalks (Fig. 1 D). Stalk with diameter of 16 ��m in basal portion of primary stalk, narrowing progressively to diameter of 8 ��m at distal ends of tertiary stalks; cortex of stalk colorless and transparent, with smooth surface and fine longitudinal striations in interior. Spasmoneme relatively more dense than cortex of stalk, with diameter of 5���6 ��m in primary stalk, narrowing progressively to diameter of 2.5 ��m at distal ends of tertiary stalks; band of mitochondria, visible as dark granules with diameter of 0.8 ��m, winding along helical path just beneath surface of spasmoneme (Fig. 1 L). Colony relatively insensitive to stimulation, requiring strong turbulence or excitation to initiate full contraction of entire colony, usually contracting only partially when touched with needle. Zooids elongate, subconical, usually 50���75 ��m (n= 11) long; body widest at peristomial lip, which measures 35���45 ��m (n= 11) in diameter (Figs. 1 A, K). Small number of enlarged zooids (macrozooid?) measuring up to 90��� 100 �� 50���60 ��m usually present on middle or distal parts of secondary stalks (Figs. 1 B, F, J). Body slightly constricted below peristomial lip, which lacks a secondary, circumferential infolding (compare with Fig. 2 A); epistomial disc moderately elevated above peristomial lip (Fig. 1 A). Pellicular striations easily visible above �� 400 magnification (Fig. 1 M), but surface of body appears uniformly smooth at low magnifications. Telotroch discoid, measuring 25���30 ��m x 50 ���60 ��m. Cytoplasm of zooids packed with tiny (0.8���1.5 ��m diameter), dense granules visible only at high magnification (�� 1000); cell colorless or slightly grayish at low magnifications. Food vacuoles and items of food within them variable in size, randomly distributed in body. Single contractile vacuole in adoral position beneath epistomial disc and near dorsal wall of infundibulum. Macronucleus C-shaped, transversely oriented, surrounding micronucleus and lower half of infundibulum (Fig. 1 A). Oral infraciliature as shown in Figures 1 H, I, N-P. Haplo- and polykinety making one and one-quarter circuits around peristome and one additional circuit within infundibulum. Haplokinety and polykinety parallel on peristome, diverging within infundibulum to lie on opposite walls (Fig. 1 H). Epistomial membrane short, located at entrance into infundibulum (arrows in Figs. 1 H, P). Germinal kinety running parallel to haplokinety in adoral half of infundibulum (Figs. 1 H, O, arrow). Each of three infundibular polykineties (P 1 ���P 3) consisting of three rows of kinetosomes. All rows of Pl terminating adstomally at level of cytostome; rows of P 2 terminating adstomally at adstomal curvature of P 1. Rows of P 2 terminating abstomally without merging with P 1; abstomal 1 / 4 of row 3 of P 2 diverging from other rows of P 2 (Figs. 1 H, I, N). All rows of P 3 terminating adstomally at point slightly beyond adstomal end of P 2 and abstomally at point approximately 1 / 3 of distance from adstomal to abstomal end of P 2. Rows 2 and 3 of P 3 closely parallel to row 1 in adstomal half, diverging from it in abstomal half, converging again with it at abstomal end of P 3 (Fig. 1 I). Trochal band consisting of band of dikinetids encircling cell at point 3 / 4 of distance from peristome to scopula. Silverline system consisting of closely spaced, parallel, transverse silverlines (Figs. 1 G, Q); 50���60 silverlines present between peristome and trochal band, 22���27 between trochal band and scopula. Pellicular pores sparsely distributed alongside silverlines (Fig. 1 Q) Remarks. The Chinese population of Z. plumula that we examined is characterized mainly by the following characters: alternately branched stalk, feather-shaped outline of colony, presence of larger zooids at some points on secondary stalks, and marine habitat. Characteristics of the colonies that we observed matched well with both the original description by Kahl (1933, 1935; Figs. 1 B, C) and the redescription by Song et al. (2002; Figs. 1 A, G). Consequently, the identification of our samples as Z. plumula is beyond reasonable doubt. In the experience of the senior author, Z. plumula is usually abundant in eutrophic waters and is accompanied by Z. alrasheidi Ji et al., 2009, which forms a large, leaf-shaped colony with a similar branching pattern. However, the latter species can be distinguished from Z. plumula easily by differences in infraciliature and number of silver lines, its larger zooids (80���120 �� 50���60 ��m vs. 50���75 �� 35���45 ��m), and its thick peristomial lip, which has a prominent circumferential infolding (Ji et al. 2009). At first glance, two other marine congeners, Z. alternans Clapar��de and Lachmann, 1859 and Z. niveum Ehrenberg, 1838, are very similar to Z. plumula in shape of the colony, branching pattern, and presence of macrozooids. However, zooids of both Z. alternans and Z. niveum have different sizes than those of Z. plumula (40���56 �� 26���32 ��m and 54���66 �� 16���22 ��m vs. 50���75 �� 35���45 ��m), and the macrozooids of both species are located on the primary stalk rather than in on the middle or distal parts of secondary branches, as in Z. plumula. In addition, Z. niveum forms a considerably larger colony (> 1 cm vs. 3 mm in Z. plumula) (Bauer-Nebelsick et al. 1996; Ji et al. 2006 b). Characters Min Max Mean SD n Number of silverlines from Z. plumula 50 60 54.5 3.36 11 peristomial lip to trochal Z. nii 47 58 52.1 3.38 15 band Z. wangi 70 85 76.4 4.63 8 P. bidulphiae 25 31 28 2.26 10 P. m a r i n a 25 30 27.5 - 4 Number of silverlines from Z. plumula 22 27 25.3 1.57 10 scopula to trochal band Z. nii 22 30 27.4 3.04 11 Z. wangi 38 50 44.2 4.46 12 P. bidulphiae 9 13 11.6 1.30 8 P. m a r i n a 10 15 12 1.79 6, Published as part of Ji, Daode, Shin, Mann Kyoon, Choi, Joong Ki, Clamp, John C., Al-Rasheid, Khaled A. S. & Song, Weibo, 2011, Redescriptions of five species of marine peritrichs, Zoothamnium plumula, Zoothamnium nii, Zoothamnium wang, Pseudovorticella bidulphiae, and Pseudovorticella marina (Protista, Ciliophora), pp. 47-59 in Zootaxa 2930 on pages 48-51, DOI: 10.5281/zenodo.278023, {"references":["Kahl, A. (1933) Ciliata libera et ectocommensalia. In: Grimpe, G. & Wagler, E., Eds., Die Tierwelt der Nordund Ostsee. Lief. 23 (Teil, II, c 3); Leipzig pp. 147 - 183.","Kahl, A. (1935) Urtiere oder Protozoa I: Wimpertiere oder Ciliata (Infusoria) 4. Peritricha und Chonotricha. Tierwelt Deutschlands, 30, 651 - 886.","Song, W., Al-Rasheid, K. A. S. & Hu, X. (2002) Notes on the poorly-known marine peritrichous ciliate, Zoothamnium plumula Kahl, 1933 (Protozoa: Ciliophora), an ectocommensal organism from cultured scallops in Qingdao, China. Acta Protozoologica, 41, 163 - 168.","Bauer-Nebelsick, M., Bardele, C. F. & Ott, J. A. (1996) Redescription of Zoothamnium niveum (Hemprich & Ehrenberg, 1831) Ehrenberg, 1838 (Oligohymenophora, Peritrichida), a ciliate with ectosymbiotic, chemoautotrophic bacteria. European Journal of Protistology, 32, 18 - 30.","Ji, D., Song, W. & Warren, A. (2006 b) Redescriptions of three marine peritrichous ciliates, Zoothamnium alternans Claparede et Lachmann, 1859, Z. sinense Song, 1991 and Z. commune Kahl, 1933 (Ciliophora: Peritrichia), from North China. Acta Protozoologica, 45, 27 - 39."]}

Redescription of Zoothamnium paraentzii Song, 1991 (Figs. 3 & 4; Table 1) Zoothamnium paraentzii was originally found in shrimp��farming waters from the Yellow Sea, China (Song 1991 a). As the original report was made in Chinese and descriptions of oral structures were not supplied in sufficient details, a complementary redescription is thus supplied based on the present population. Improved diagnosis: Marine Zoothamnium irregularly dichotomously branched with zooids of the same branch born on the same side. Body highly variable in shape but usually elongate, measuring about 50���80 �� 25���45 ��m. Peristomial lip single layered; contractile vacuole apically located; macronucleus generally C��shaped and horizontally orientated; number of transverse lines from oral area to aboral trochal band 75���83, from aboral trochal band to scopula, 28���33; inner row of peniculus 3 displaced from the other two and converged with peniculus 1 at aboral end. Voucher slides: Two permanent slides (registration numbers: 0 4040601, 04040602) with silver nitrate and protargol prepared material are deposited at the Laboratory of Protozoology, OUC, China. Morphology: Body flexible and highly variable, usually slender vase��shaped (Figs. 3 A, 3 D; 4 B, 4 D), widest at oral border, and slightly constricted below peristomial lip. Fully extended zooid ca. 60 �� 40 ��m in size, ratio of length to width mostly about 3: 2. Peristomial disk moderately elevated (Fig. 4 D). Single��layered peristomial lip relatively thin (Figs. 3 A, 3 D; 4 B). Pellicle smooth at low magnification, striations detectable at higher magnification (�� 400 or higher). Cytoplasm colourless and transparent, usually becoming denser and more granular in aboral part of cell owing to presence of numerous tiny granules (ca. 2���6 ��m in diameter) and several food vacuoles (Figs. 3 A, 3 D; 4 B, 4 D). Macronucleus relatively short, Cshaped and horizontally orientated (Fig. 4 I). Single large contractile vacuole apically located (Figs. 3 A; 4 B). Stalk robust, about 8���12 ��m thick, with many drapes on surface (Figs. 3 F, arrows; 4 C, arrows). Colony irregularly dichotomously branched with zooids of the same branch born on the same side and reaching a total length up to 1 mm (Figs. 3 E; 4 A). Stalk myoneme conspicuous with numerous grayish thecoplasmic granules which measuring about 0.5 ��m in diameter (Figs. 3 F; 4 C). Oral apparatus typical of genus. Haplokinety and polykinety circling about one and half turns around peristomial disc and accomplishing a further turn after plunging into vestibulum (Fig. 3 H). Near distal end of haplo�� and polykinety, always one short kinety fragment recognizable (Figs. 3 H, arrow; 4 H, arrow). P 1 composed of three rows terminating at different levels with shortest (inner) row next to P 3 and longest row opposite. P 2 terminates distinctly above and between P 1 and P 3, row neighbouring P 1 usually short than the other two rows (Figs. 3 H; 4 E). P 3 also with three rows, and always terminating slightly above P 1; the inner row slightly displaced to the other two and converged with P 1 at its aboral end (Fig. 3 H). Germinal kinety located parallel to haplokinety (Figs. 3 H; 4 G, double arrowhead). Epistomial membrane short, near the opening of vestibulum (Figs. 3 H, double arrowhead; 4 I, arrow). Aboral trochal band appears as a fine zigzag row of kinetosomes which encircle cell in posterior region (Fig. 4 H, arrowheads). FIGURE 3. Morphology of Zoothamnium paraentzii from live cells (A���F), after silver nitrate (G) and protargol (H, I) impregnations. (A) A general view of a typical zooid. (B) Colony form (from Song 1991). (C) Zooid at low magnification (from Song 1991). (D) Zooid at low magnification. (E) Colony form. (F) Detail of stalk, with conspicuous thecoplasmic granules in spasmoneme and arrows show drapes on the stalk. (G) Silverline system. (H) General oral infraciliature, arrow notes the distal kinety fragment, double arrowhead marks the epistomial membrane. (I) Oral structure (from Song 1991). ATB = aboral trochal band; G = germinal kinety; H = haplokinety; P 1���3 = peniculus 1���3; Po = polykinety. Scale bars in (A) = 20 ��m, in (E) = 200 ��m. Silverline system consisting of many parallel, transverse rows, numbering 75���83 (mean 79) from oral area to aboral trochal band, 28���33 (mean 31) from aboral trochal band to scopula with sparsely distributed pellicular pores (Figs. 3 G; 4 F). FIGURE 4. Photomicrographs of Zoothamnium paraentzii from live cells (A���D), after protargol (E, G���I) and silver nitrate (F) impregnation. (A) Colony form. (B) A typical zooid, arrow to mark the contractile vacuole. (C) Stalk and spasmoneme, arrows note drapes on the surface of stalk. (D) Zooids at 400 �� magnification, demonstrating flexible body. (E) Oral peniculi. (F) Silverline system. (G) Lateral view, double arrowhead marks germinal membrane. (H) Lateral view, arrow notes the oral distal fragment and arrowheads mark the aboral trochal band. (I) Lateral view, arrow to show the epistomial membrane. Ma = macronucleus; P 1 ��� 3 = peniculus 1���3. Scale bars in (A) = 300 ��m, in (B, D) = 30 ��m. Comparison and discussion The special arrangement of individuals, irregularly dichotomously branching style, variable body shape, apically located contractile vacuole, high number of silverlines and marine habitat of the current population matches well to the holotype, which was found as an ectocommensal organism on the shrimp (Song 1991 a) (Figs. 3 B, 3 C). In original description, the P 3 was described as having only two rows of kineties (Fig. 3 I). Based on a reexamination on the holotype, the peniculus 3 is composed of three rows which matched hence the present form. Considering the living appearances and the marine habitat, some Zoothamnium species with dichotomously branched stalk and single��layered peristomial lip should be compared with the current organism: Z. dichotomum Wright��Kent, 1882; Z. intermedium Precht, 1935; Z. paragammari Song, 1991; Z. marinum Mereschkowski, 1879. Morphologically, Zoothamnium paraentzii shares many similarities with Z. dichotomum Wright��Kent, 1882 (Figs. 5 J, 5 K) (Table 2). Although the oral apparatus and silverline system, even the body size of Z. dichotomum remains unknown, it can be separated from Z. paraentzii by the regularly dichotomously branching form with zooids located in pairs (vs. irregularly dichotomous branching style with zooids of the same branch born on the same side) and clearly more aboral position of the contractile vacuole (below peristomial lip vs. apically positioned) (Kahl 1935). Zoothamnium paraentzii can be clearly distinguished from Z. intermedium Precht, 1935 (Figs. 5 Q, 5 R) (Table 2) (Song 1991 b) by its irregularly, dichotomously branching form and larger cell size. Zoothamnium paragammari Song, 1991 (Figs. 5 N, 5 O) (Table 2) also has a similar size and body shape. However, it can be separated from Z. paraentzii by its having distinctly fewer transverse silverlines (57 vs. 75���83) (Song 1991 b) from the peristome to the trochal band. In addition, the structure of peniculus 3 is completely different. In terms of body shape and position of contractile vacuole, Zoothamnium marinum Mereschkowski, 1879 (Fig. 5 P) (Table 2) is also similar to Z. paraentzii. As the silverline system and infraciliature of Z. marinum remains unknown, the conspicuously larger body size (100 vs. 34 ��m after fixation) could be the solely useful distinguishing character (Kahl 1935). Another species, Zoothamnopsis mengi Song, 1997 (Figs. 5 L, 5 M), might also be related to the present form in the colony form, appearance of peristomial lip and body shape (Table 2). However, it differs from Zoothamnium paraentzii at least by distinctly different silverline system (Pseudovorticella �� type vs. Vorticella �� type) (Song 1997). In addition, the arrangement of the living individuals of Zoothamnium paraentzii is special (zooids of the same branch born on the same side), which distinguishes it from most other known congeners and therefore could be an easily observable feature used for identification of this taxon in ecological studies., Published as part of Sun, Ping, Ji, Daode & Song, Weibo, 2005, Notes on a new marine peritrichous ciliate (Ciliophora: Peritrichida), Zoothamnium xuianum n. sp., with redescription of Z. paraentzii Song, 1991 from northern China, pp. 41-53 in Zootaxa 1075 on pages 47-51, DOI: 10.5281/zenodo.170316, {"references":["Song, W. (1991 a) A new marine ciliate, Zoothamnium paraentzii nov. spec. (Ciliophora, Peritrichida). Zoological Research, 12, 355 - 359 (in Chinese with English summary).","Precht, H. (1935) Epizoen der Kieler Bucht. Nova Acta Leopoldina, 3, 405 - 474.","Kahl, A. (1935) Urtiere oder Protozoa I: Wimpertiere oder Ciliata (Infusoria). 4. Peritricha und Chonotricha. In: Dahl, F. (Ed.), Die Tierwelt Deutschlands, 30, 651 - 886.","Song, W. (1991 b) Contribution to the commensal ciliates on Penaeus orientalis II. (Ciliophora, Peritrichida). Journal of Ocean University of Qingdao, 21, 45 - 55 (in Chinese with English summary).","Song, W. (1997) A new genus and two new species of marine peritrichous ciliates (Protozoa, Ciliophora, Peritrichida) from Qingdao, China. Ophelia, 47, 203 - 214."]}

Sun, Ping, Song, Weibo, Ji, Daode, Hu, Xiaozhong (2005): 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. Journal of Natural History 39 (32): 2953-2965, DOI: 10.1080/00222930500239785, URL: http://dx.doi.org/10.1080/00222930500239785