Hemiholosticha pantanalensis, Vďačný & Foissner, 2019
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publication ID |
https://doi.org/ 10.4467/16890027AP.19.010.11419 |
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publication LSID |
lsid:zoobank.org:pub:CD5225C9-1364-4F39-B37C-D207E268B38D |
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persistent identifier |
https://treatment.plazi.org/id/BE39471F-C249-41E5-97D2-42584EF3FB65 |
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taxon LSID |
lsid:zoobank.org:act:BE39471F-C249-41E5-97D2-42584EF3FB65 |
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treatment provided by |
Felipe |
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scientific name |
Hemiholosticha pantanalensis |
| status |
sp. nov. |
Hemiholosticha pantanalensis nov. spec. Foissner and Vďačný
ZooBank registration number: urn:lsid:zoobank.org:act:BE39471F-C249-41E5-97D2-42584EF3FB65 .
Diagnosis: Size in vivo about 70 × 53 µm; body almost globular to broadly obovate with short anterior projection at distal end of adoral zone; dorsal side with three distinct ribs. Two ellipsoid macronuclear nodules and a single micronucleus in between. On average a total of 35 cirri in three ventral, one postoral, one right and one left marginal row. Two postoral cirri, first localized at level of proximal end of undulating membranes. On average 30 dorsal bristles in three kineties, posterior bristles elongated. Adoral zone extends about 60% of body length, composed of an average of 21 membranelles. Green intracellular algae with eyespot present.
Type locality: Dusty , light brown soil from the Pantanal wetland, Mato Grosso, Brazil, S16°39ʹ W56°45’ GoogleMaps .
Type material: The holotype slide and two paratype slides with protargol-impregnated specimens have been deposited in the Museum of Natural History (Biologiezentrum) in Linz ( LI), Austria. The holotype ( Fig. 1B, C View Fig ) and relevant paratype specimens as well as dividers have been marked by black ink circles on the coverslip .
Etymology: The species-group name pantanalens·is -is, - e [m, f, n] is a Latin adjective in nominative singular (Article 11.9.1.1 of the International Commission on Zoological Nomenclature 1999) and refers to the origin of the new species.
Description: Size in vivo 60–76 × 48–60 µm, on average 70 × 53 µm, i.e., distinctly longer and wider than in protargol and SEM preparations (50 × 35 µm and 50 × 33 µm) ( Table 1). Body almost globular to broadly obovate with a length:width ratio ranging from 1.1:1 to 1.8: 1 in protargol preparations; a short anterior projection at distal end of adoral zone; posterior end usually broadly rounded but often narrower than anterior end, rarely acute, especially in ventral view; right cell margin very thin and hence appearing hyaline in vivo ( Table 1; Figs 1A–C, E–H View Fig , 2A–F, I–K View Fig , 3A–C View Fig , 4A View Fig ). Dorsoventrally flattened up to 2:1, both sides slightly to moderately convex, dorsal side with three prominent, sharp ribs well recognizable in SEM and in optical cross sections during live observation ( Figs 1I View Fig , 3B, C View Fig , 4A View Fig , 5A–D View Fig ). Nuclear apparatus in central quarters of cell, almost in body midline; invariably composed of two macronuclear nodules and one micronucleus in between. Macronuclear nodules broadly ellipsoid, ellipsoid or ovoid with a length:width ratio of 1.3–2.1:1; size about 9.0–15.0 × 6.0–9.0 µm, usually 11.7 × 7.6 µm in protargol preparations; distance between nodules rather variable (CV = 26.3%), ranging from 2.0 µm to 6.0 µm; nodules usually connected by a fine strand impregnated with protargol; nucleoli globular and up to 3.0 µm across. Micronucleus bright, broadly ellipsoid to ellipsoid, i.e., about 5.0 × 3.0 µm in vivo and 4.0–5.0 × 2.0–3.0 µm, on average 4.5 × 2.6 µm in protargol preparations ( Table 1; Figs 1A, C, F View Fig , 2I–K View Fig ). Contractile vacuole near body centre; a single excretory pore, about 1.0 × 0.3 µm in SEM, left of middle dorsal rib, not recognizable in protargol preparations ( Figs 1A View Fig , 2D, F View Fig , 5C, D View Fig ). Cortex inflexible, colourless, lacks specific granules. Cytoplasm colourless but cells appear greenish due to numerous green algae; finely granulated; studded with lipid droplets 0.5–5.0 µm across and some up to 10 µm-sized food vacuoles containing Polytoma cysts. Green algae almost fill cili- ate’s body; 10–13 × 4–7 µm in size in vivo (n = 11); ellipsoid to narrowly ellipsoid; with subapical intraplastidial red eyespot (stigma), some starch granules, and comparatively large chloroplast almost completely encircling the cell; division yields four tightly packed daughter cells ( Figs 1J, K View Fig , 2G, H, K View Fig ). Glides and creeps moderately fast on microscope slides, also rests on organic debris.
Cirri firm, thorn-like, 17–20 µm long in vivo while only 11–16 µm after protargol impregnation and 10–20 µm (on average 13.5 µm) in SEM; total number very stable (CV = 4.2%) ranging from 31 to 36; arranged in three ventral, one postoral, one right and one left marginal row; frontal, buccal, and transverse cirri not distinguishable ( Table 1; Figs 1B, E View Fig , 2J View Fig ). Ventral cirral row R1 invariably composed of two cirri: anterior cirrus near distal end of adoral zone, posterior cirrus slightly anterior to mid-portion of paroral membrane. Ventral cirral row R2 begins 6.0–11.0 µm posterior to anterior body end; 5.0 µm to 7.0 µm long after protargol impregnation; invariably composed of two cirri.
Characteristicsa Mean M SD SE CV Min Max n Body, length 49.4 50.0 4.9 1.0 10.0 40.0 57.0 23
Body, length in SEM 49.6
Body, length in vivo 69.6
Body, width 35.7
Body, width in SEM 33.5
Body, width in vivo 52.8
Body length:width, ratio 1.4
Anterior projection, height 2.0
Macronuclear nodules, number 2.0
Micronuclei, number 1.0
Anterior body end to anterior macronuclear nodule, distance 10.5
Macronuclear nodules, distance in between 3.7
Anterior macronuclear nodule, length 11.7
Anterior macronuclear nodule, width 7.6
Anterior macronuclear nodule length:width, ratio 1.5
Nucleoli, maximum diameter 3.0
Micronucleus, length 4.5
Micronucleus, width 2.6
Micronucleus length:width, ratio 1.4
Anterior body end to proximal end of AZM, length 29.4
Adoral zone of membranelles, percentage of body length 59.6
Adoral membranelles, number 21.2
Adoral membranelles, length of widest base 6.5
Frontal adoral membranelles, length of cilia 16.4
Buccal cavity, width 8.8
Anterior body end to paroral membrane, distance 5.9
Paroral membrane, length 17.0
Anterior body end to endoral membrane, distance 13.7
Endoral membrane, length 10.0
Left marginal cirral row, number of cirri 5.4
Postoral cirral row, number of cirrib 2.0
Anterior body end to postoral cirral row, distance 22.3
Postoral cirral row, length 10.1
Ventral cirral row R1, number of cirri 2.0
Ventral cirral row R1, length 4.4
Ventral cirral row R2, number of cirri 2.0
Anterior body end to ventral cirral row R2, distance 9.0
Ventral cirral row R2, length 6.0
Ventral cirral row R3, number of cirri 11.5
Right marginal cirral row, number of cirri 11.7
Cirri, total number 34.5
Cirri, length 14.3
Dorsal kinety 1, number of bristles 7.0 49.0
70.0
35.0
33.0
52.0
1.4
2.0
2.0
1.0
11.0
3.0
12.0
8.0
1.5
30.0
4.5
2.5
1.3
30.0
59.2
21.0
7.0
16.0
9.0
6.0
17.0
14.0
10.0
5.0
2.0
22.0
10.0
2.0
4.0
2.0
10.0
6.0
12.0
12.0
35.0
15.0
7.0
6.7 1.4 13.5 40.0 73.0 23
4.3 1.4 6.2 60.0 76.0 10
4.4 0.9 12.4 30.0 46.0 23
4.5 0.9 13.3 25.0 46.0 23
3.7 1.2 7.0 48.0 60.0 10
0.1 0.0 10.7 1.1 1.8 23
0.6 0.1 28.8 1.0 3.0 21
0.0 0.0 0.0 2.0 2.0 23
0.0 0.0 0.0 1.0 1.0 21
1.1 0.2 10.2 8.0 12.0 21
1.0 0.2 26.3 2.0 6.0 21
1.7 0.4 14.9 9.0 15.0 21
0.7 0.2 9.9 6.0 9.0 21
0.2 0.1 14.9 1.3 2.1 21
0.0 0.0 0.0 3.0 3.0 3
– – – 4.0 5.0 21
– – – 2.0 3.0 21
0.2 0.0 13.7 1.2 1.8 21
1.8 0.4 6.1 26.0 33.0 21
3.8 0.8 6.4 54.5 66.7 21
0.8 0.2 3.8 20.0 23.0 21
– – – 6.0 7.0 21
1.5 0.4 9.2 15.0 20.0 12
1.0 0.2 11.7 7.0 11.0 21
1.4 0.3 24.3 3.0 8.0 21
1.6 0.4 9.7 13.0 19.0 21
1.7 0.4 12.4 10.0 16.0 21
0.7 0.2 7.1 9.0 11.0 21
– – – 5.0 6.0 21
0.0 0.0 0.0 2.0 2.0 42
2.2 0.5 10.0 18.0 26.0 21
1.2 0.3 12.2 8.0 13.0 21
0.0 0.0 0.0 2.0 2.0 21
0.7 0.1 15.3 3.0 6.0 21
0.0 0.0 0.0 2.0 2.0 21
1.7 0.4 18.9 6.0 11.0 21
0.7 0.1 11.2 5.0 7.0 21
0.6 0.1 5.2 10.0 12.0 21
0.6 0.1 5.5 11.0 13.0 21
1.4 0.3 4.2 31.0 36.0 21
1.4 0.4 9.6 11.0 16.0 12
0.9 0.2 12.3 6.0 9.0 21 Anterior body end to dorsal kinety 1, distance 14.0
Posterior body end to dorsal kinety 1, distance 10.3
Dorsal kinety 2, number of bristles 10.2
Anterior body end to dorsal kinety 2, distance 9.5
Dorsal kinety 3, number of bristles 13.1
Anterior body end to dorsal kinety 3, distance 5.3
Dorsal bristles, total number 29.9
Posterior dorsal bristles, length 8.4
Anterior dorsal bristles, length 3.5
Intracellular green algae, length in vivo 10.7
14.0 1.9 0.4 13.9 10.0 18.0 21
11.0 3.2 0.7 31.1 5.0 18.0 21
10.0 1.0 0.2 9.6 8.0 12.0 21
10.0 1.4 0.3 15.1 7.0 12.0 21
13.0 1.1 0.2 8.3 11.0 16.0 21
5.0 1.2 0.3 22.4 3.0 8.0 21
30.0 3.1 0.7 10.4 20.0 35.0 21
8.0 0.7 0.2 8.1 7.0 9.0 21
3.0 – – – 3.0 4.0 21
11.0 1.6 0.5 15.1 7.0 13.0 11
Intracellular green algae, width in vivo 5.1 4.0 1.4 0.4 27.0 4.0 7.0 11
a Data based, if not stated otherwise, on mounted, protargol-impregnated, and randomly selected specimens from a raw culture. Measurements in µm. AZM – adoral zone of membranelles; CV – coefficient of variation (%); M – median; Max – maximum; Mean – arithmetic mean; Min – minimum; n – number of individuals investigated; SD – standard deviation; SE – standard error of arithmetic mean. b Of 45 specimens investigated, one did not have postroral cirri and two other cells had one, respectively, three cirri .
Ventral cirral row R3 conspicuously longer than R1 and R2; extends from anterior to posterior body end in slightly curved pattern; consists of 10–12 (rarely 13) cirri, anterior cirri more widely spaced than posterior ones. Postoral cirral row typically composed of two cirri; zero, one or three cirri in three out of 45 specimens; anterior cirrus about at level of proximal end of paroral membrane, posterior cirrus near proximal end of adoral zone; distance between postoral cirri ranges from 8.0 µm to 13.0 µm in protargol preparations, causing problems in discerning the postoral row. Right marginal cirral row begins at anterior body end, extends along body margin following its curvature to terminate near rear body end; consists of 11–13 cirri. Left marginal cirral row commences at level of mid-portion of adoral zone and terminates at level of right marginal cirral row; composed of five or six cirri (Table 1; Figs 1B, E View Fig , 2J View Fig , 3A–D View Fig , 4A, B View Fig ).
Dorsal bristles fine, increase in length from 3.0–4.0 µm anteriorly to 7.0–9.0 µm posteriorly; total number of bristles moderately variable (CV = 10.4%) ranging from 20 to 35; arranged in three meridional rows; posteriormost bristles of second and third row protrude beyond posterior end of cell. Dorsal kinety 1 begins subapically, shortened posteriorly, and composed of 6–9 bristles. Dorsal kineties 2 and 3 also commence subapically but terminate at rear body end, consist of 8–12 and 11–16 bristles, respectively. Caudal cirri absent ( Table 1; Figs 1C, D, F View Fig , 5A, B View Fig ).
Adoral zone extends about 60% of body length on average; commences anteriorly near midline of body and forms a question mark-like pattern in ventral view; composed of an average of 21 membranelles. Individual membranelles composed of four rows of basal bodies: rows 1 and 2 long and ciliated, row 3 slightly shorter and with minute cilia or unciliated according to SEM observations, row 4 minute, very likely unciliated; length of membranellar cilia abruptly increases from 5 µm to 20 µm in distal half of zone, causing conspicuous frontal membranelles; largest bases of membranelles 10 µm wide in vivo while only 6.0–7.0 µm after protargol impregnation ( Table 1; Figs 1A, B, E View Fig , 2I–K View Fig , 3A–D View Fig , 4A–D View Fig ). Scutum crescentic, emerges slightly anterior to beginning of ventral cirral row R2 and merges into margin of membranellar stripe partially covering frontal membranelles ( Figs 3C, D View Fig , 4A, B View Fig ).
Buccal cavity almost as long as ventral portion of adoral zone; about 7.0–11.0 µm wide in protargol preparations; right margin elevates into a conspicuous Cshaped ridge anteriorly merging into scutum and posteriorly into buccal vertex ( Table 1; Figs 3A–D View Fig , 4A, B View Fig ). Paroral membrane begins about 6 µm posterior to anterior body end; extends crook-like over buccal ridge, resembling the cyrtohymenid pattern; about 17 µm long in protargol preparations and shorter than adoral zone proximally and distally; composed of narrowly spaced dikinetids but only one basal body ciliated according to SEM observations; cilia up to 15 µm long in vivo, gradually decreasing to 7 µm at both ends; posterior portion rarely doubled or triplicated according to SEM observations ( Table 1; Figs 1B, E View Fig , 2C, E, I, J View Fig , 3A–D View Fig , 4A–D View Fig ). Endoral membrane begins in mid of buccal cavity, i.e., about 14 µm posterior to anterior body end; optically intersects paroral membrane and terminates at level of or slightly posterior to its proximal end; about 10 µm long in protargol preparations and hence distinctly shorter than paroral membrane; composed of densely spaced basal bodies; cilia 7 µm long in vivo, form a plate-like structure at bottom of buccal cavity indicating that they might be motionless ( Table 1; Figs 1B, E View Fig , 2J View Fig , 4A–C View Fig ). Buccal seal present in some specimens ( Fig. 4A–C View Fig ).
| LI |
Biology Centre of the Upper Austrian State Museum - Herbarium |
| CV |
Municipal Museum of Chungking |
| M |
Botanische Staatssammlung München |
| SD |
San Diego Natural History Museum |
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.
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