Paralitonotus foissneri Zhang & Zhao & Chi & Warren & Pan & Song 2022, SP. NOV.
Creators: name: Zhang, Gongaote
name: Zhao, Yan
name: Chi, Yong
name: Warren, Alan
name: Pan, Hongbo
name: Song, Weibo
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Chromista
Ciliophora
Gymnostomatea
Pleurostomatida
Protolitonotidae
Paralitonotus
Paralitonotus foissneri

description: PARALITONOTUS FOISSNERI SP. NOV.
(FIGS 2, 3; TABLE 1)
Zoobank registration: urn: lsid: zoobank. org:act: 39F1669A-2ED6-41BF-A718-CF3584918B9C
Diagnosis: Cell elongate and extremely contractile, with long neck ~40–50% of body length, posterior portion of body conspicuously tail-like; size in extended individuals about 150–300 µm × 30–50 µm; six or seven left and 13–15 right somatic kineties; single subterminal contractile vacuole; two macronuclear nodules and single micronucleus; marine habitat.
Type material: A silver proteinate slide with the holotype specimen circled by ink and a second silver proteinate slide with paratype specimens were deposited in Laboratory of Protozoology, Ocean University of China, with registration numbers CY2018101603-1 and CY2018101603-2, respectively.
Type locality and ecological features: Intertidal zone of a sandy beach in Qingdao, China (36°16′35.817″N, 120°40′32.0124″E). Water temperature 21 °C and salinity 30 ‰.
Etymology: We dedicate this species to Professor Dr Wilhelm Foissner, University of Salzburg, Austria, in recognition of his significant contributions to ciliatology.
SSU rDNA sequence: The partial SSU rDNA gene sequence of Pa. foissneri sp. nov. is deposited in GenBank with length 1593 bp, G+C content 42.81% and accession number MW414674. The SSU rDNA gene sequence similarity between Pa. foissneri sp. nov. and its similar species ranges from 0.901 to 0.973 (Fig. 8).
Description: Body size highly variable, cell length mostly ~150–300 µm, contracts ≤ 50%, occasionally> 350 µm when fully extended. Main body spindle shaped, ~70–170 µm long, with neck ~40–50% and tail ~15% of cell length (Figs 2A, B, F, 3A–E, I). Cilia in right kineties are ~6 µm long in vivo and densely arranged, whereas those in left kineties are undetectable in live cells. Nuclear apparatus centrally located, comprising two ovoidal macronuclear nodules, each about 10–30 µm × 5–10 µm after silver proteinate staining, and a single micronucleus (Figs 2A, B, D, G, 3K, M). Micronucleus located between two macronuclear nodules (Fig. 3M, arrowhead). Single contractile vacuole subterminally located (Figs 2A, B, 3C), pulsates about every 2 min. Extrusomes scattered in main body (Figs 2F, H, 3H), straight or slightly curved, ~4 µm long in vivo (Fig. 2C). Extrusomes in oral bulge undetected. Cortical granules not observed. Cytoplasm colourless or greyish, with numerous endoplasmic granules (~1–3 µm in diameter) in main body, rendering this region opaque. Locomotion typically by swimming, with anterior portion repeatedly contracting and swinging from side to side, sometimes by gliding on substrate.
Ciliary pattern as shown in Figures 2E, G–I, 3J, L. About 14 (13–15) right somatic kineties, middle one longest, terminating anteriorly about one-sixth down the length of the body (Figs 2E, G–I, 3J, L; Table 1). Anterior of rightmost kinety terminating at one-third down length of cell, second rightmost kinety (RK n −1) extending to anterior and posterior ends of cell as a full kinety. Other right somatic kineties progressively shortened anteriorly towards dorsal and ventral margins to form two semi-sutures along dorsal full RK n −1 and PK2, respectively (Figs 2G–I, 3L). Left side sparsely ciliated, with six or seven kineties (including PK1; Fig. 2E, H; Table 1). Dorsal brush kinety consisting of dikinetids in anterior half of cell and monokinetids in posterior half (Fig. 2E). Leftmost left kinety (LK n) extending to anterior end of cell (Fig. 2E, H). Two perioral kineties (PKs), one either side of oral slit, both consisting of densely spaced dikinetids in anterior 30%, continuing posteriorly as a row of monokinetids (Fig. 2E, H).
description: Published as part of Zhang, Gongaote, Zhao, Yan, Chi, Yong, Warren, Alan, Pan, Hongbo & Song, Weibo, 2022, Updating the phylogeny and taxonomy of pleurostomatid ciliates (Protista: Ciliophora) with establishment of a new family, a new genus and two new species, pp. 105-123 in Zoological Journal of the Linnean Society 196 (1) on pages 108-110, DOI: 10.1093/zoolinnean/zlac028, http://zenodo.org/record/7035078