Morphological Redescriptions and Molecular Phylogeny of Three Stentor Species (Ciliophora: Heterotrichea: Stentoridae) from Korea
Author
Taher, Md Abu
Author
Kabir, Ahmed Salahuddin
Author
Shazib, Shahed Uddin Ahmed
Author
Kim, Min Seok
Author
Shin, Mann Kyoon
text
Zootaxa
2020
2020-02-13
4732
3
435
452
journal article
24039
10.11646/zootaxa.4732.3.6
ea9ffdde-e6b1-4e98-a8aa-93c6a67591fe
1175-5326
3667262
76254E06-3555-4C8D-9B25-1DF8BD9C55ED
Stentor tartari
Murthy & Bai, 1974
(
Figs. 6–8
,
Tables 1
,
2
)
Improved diagnosis.
Body size 200–355 ×
85–135 µm
in vivo
(on average 300 ×
105 µm
), 250–700 ×
70–135 µm
when extended, about 200 ×
160 µm
after protargol impregnation. Body slender trumpet-shaped to conical when extended, irregular pinkish and colorless cortical granules scattered throughout whole body, symbiotic green algae present, contractile vacuole located in anterior 1/3 of body near left margin with a collecting canal, 8–13 peristomial kineties, 62–106 somatic ciliary rows, 1–4 (average 2) macronuclear nodules located at mid-body. 5–18 micronuclei located around macronuclear nodules.
Locality and habitat.
Small freshwater pond (0 psu), Cheongnyang-myeon, Ulju-gun,
Ulsan
,
Korea
(35°31′
47°N
, 129°13′
41°E
).
Voucher material.
A protargol-stained slide with fixed specimens was deposited at the National Institute of Biological Resources (
NIBR
),
Incheon
,
Korea
, with registration number NIBRPR0000107178. The voucher specimens are marked by a black ink circles on the slide.
FIGURE 6.
Line diagrams of
S
.
tartari
from life (A–D) and after protargol impregnation (E, F).
A.
Ventral view of a representative specimen;
B.
Cortical granulation;
C.
Somatic cilia;
D.
Body shapes of freely motile and extended cells;
E, F.
Ventral and dorsal views of infraciliature; Arrowhead in (E) point to basal bodies of somatic cilia. AM, adoral membranelles; AZM, adoral zone of membranelles; CG, cortical granules; CV, contractile vacuole; MA, macronucleus; MI, micronuclei; PK, peristomial kinety; PM, paroral membrane; SC, somatic cilia; SK, somatic kinety. Scale bars: A= 100 μm, C=10 μm, E, F=50 μm.
Description.
The freely motile cell is inverted pear-shaped and size ranges, 200–355 ×
85–135 µm
(on average 300 ×
105 µm
)
in vivo
(
Fig. 7A
). After extension, when cell relaxed, the body looks like trumpet-shaped and size ranges,
250–700 µm
in length and
70–135 µm
in width in the peristomial area. Specimens shrink considerably after protargol impregnation, i.e., 95–310 ×
75–230 µm
(on average 200 ×
160 µm
) (
Fig. 8A
). Two
types
of cortical granules, colored and colorless, irregularly arranged between somatic kineties (
Fig. 7C, D
). The colored cortical granules appeared pinkish red, reddish, or brown red, round or oval-shaped
0.5–1 µm
in diameter (
Fig. 7C, D
). Density of the colored cortical granules is higher in anterior than in mid to posterior parts of body (
Fig. 7A
). Colorless cortical granules are smaller than reddish granules; shape of colorless cortical granules is round to oval,
0.3–0.5 µm
in diameter (
Fig. 7C
). Transparent cortex makes cytoplasmic organelles easily identifiable (
Fig. 7A, C, F
). Sixtytwo to 106 parallel somatic kineties composed of dikinetids longitudinally arranged parallel to antero-posterior axis of cell (
Fig. 6E, F
,
7C
,
8B
). Each somatic cilium is
6–12 µm
long (
Fig. 7D
). Average gap between adjacent somatic kineties is
7 µm
in vivo
. Mitochondria (?)-like organelles distributed on pellicle slightly more densely packed near somatic kineties (
Fig. 7D
, arrowhead). One contractile vacuole with a long collecting canal located left of the buccal cavity about
35 µm
in diameter during diastole (
Fig. 6A
,
7G
). Eight to 17 peristomial kineties were observed in peristomial region (
Fig. 6E
,
7B
,
8B
) and size of peristomial cilia was similar to the size of somatic cilia. Buccal pouch absent. Adoral zone of membranelles conspicuous consist of 110–180 membranelles (
Fig. 6E
,
7B
,
8B
). Adoral zone of membranelles surrounds the peristome and finally ends at the buccal cavity (
Fig. 7A
,
8A
). The longest adoral membranelle,
12 µm
long. The Paroral membrane is typical of the genus, consisted of a single and continuous row of thin cilia,
20–35 µm
long (
Fig. 6E
,
8B
). Nuclear apparatus comprised of 1–5 spherical macronuclear nodules (on average 2), about
20–35 µm
in diameter
in vivo,
usually located at the mid-body, however the position of macronuclear nodules is not fixed (
Fig. 7A, F
,
8A, C
). Five to 18 spherical micronuclei with a diameter of
1–2 µm
in vivo
adjacent to macronuclear nodules (
Fig. 7F
,
8C
). Symbiotic algae,
2–4 µm
in diameter
in vivo
, present throughout body giving it a dark to light green appearance (
Fig. 7A, E
,
8A
). Food vacuoles are
5–30 µm
in diameter; contain bacteria, diatoms as food (
Fig. 6A
). Lipid droplets
2–5 µm
in diameter scattered throughout body. Holdfast organelle present at posterior end of cell (
Fig. 7E
, inset: arrowhead); colored cortical granules densely packed in this region exhibiting a red appearance (
Fig. 7A
).