Holosticha antarctica, Wilbert & Song, 2008
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publication ID |
https://doi.org/ 10.1080/00222930701877540 |
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persistent identifier |
https://treatment.plazi.org/id/03B587B3-FF8D-C440-FE6A-64F0FCCBFC88 |
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treatment provided by |
Felipe |
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scientific name |
Holosticha antarctica |
| status |
sp. nov. |
Holosticha antarctica View in CoL nov. spec.
( Figures 2A–H View Figure 2 , 11A–M View Figure 11 ; Table 2)
Diagnosis
Band-like, flexible marine Holosticha about 300–500×80 Mm in vivo with brownreddish colour; ca. 70 adoral membranelles extending to about 25–30% of cell length; 70–80 left and 60–70 right marginal cirri; about 40 pairs of cirri in midventral rows which terminate at the transverse cirri; about five frontal, one buccal, 3–6 frontoterminal and 5–8 transverse cirri; consistently three dorsal kineties; more than 100 macronuclear nodules.
Type locality
Benthos samples from rockpools and the littoral zone on the sea coast near Bellinghausen Station, King George Island (62 ° 139S, 58 ° 589W).
Description
Size mostly about 400 Mm long, body like a long band with parallel body margins, very flexible but not contractile ( Figure 2E View Figure 2 ). Buccal field prominent, about 30% of cell length. Dorsoventrally flattened, cell in central portion often conspicuously thicker than at the margins ( Figure 2A View Figure 2 ). Pellicle thin, no cortical granules observed although cytoplasm evenly dark brownish or brick-reddish in colour as observed under low magnification. Cytoplasm with many tiny granules and lipid droplets; contractile vacuole not observed ( Figure 2A View Figure 2 ). More than 100 macronuclear nodules scattered throughout the cell, spherical to ellipsoid, often several large, ellipsoid micronuclei recognized in protargol-impregnated specimens.
Cilia in all ciliary organelles relatively inconspicuous and fine. Movement without pause, usually in a snake-like way, crawling medium or fast on bottom of Petri dish or debris.
Adoral zone extending far onto right side. Membranelles in proximal part conspicuously (up to five times!) longer than those in distal portion ( Figure 2D View Figure 2 ). Paroral membrane (PM) about half as long as the endoral (EM), both straight or slightly curved, optically appearing to intersect ( Figure 2D View Figure 2 ). One buccal cirrus (BC) at anterior paroral level ( Figure 2D View Figure 2 ).
About five frontal cirri (FC), which are often not clearly distinguished from the midventral cirri posteriorly although the anteriormost (usually 3–4) cirri are conspicuously enlarged ( Figures 2D View Figure 2 , 11D, G View Figure 11 ). Frontoterminal cirri (FTC) mostly 5–6, near the distal end of adoral zone ( Figure 2D View Figure 2 ). Midventral rows (MVR) in typical zigzag pattern, terminating near transverse cirri (TC, Figures 2F–H View Figure 2 ). 5–8 transverse cirri slightly enlarged and closely arranged in J-shape, which are often difficult to separate from the marginal rows ( Figures 2F–H View Figure 2 ; 11I, L, M View Figure 11 ). Marginal rows not confluent posteriorly. Dorsal kineties (DK) consistently three in number, densely ciliated, bearing 3.5–5.0 Mm long bristles ( Figures 2B View Figure 2 , 11H View Figure 11 ); without caudal cirri.
Remarks
Due to the combination of long band-shaped body, very flexible ( Figures 2E View Figure 2 ) extremely large size, conspicuously long buccal field, brownish to brick-reddish colour, marine habitat and features of infraciliature, the new species can be clearly distinguished. The detailed ciliary structure of Holosticha fasciola Kahl, 1932 evidently remains unknown, but it seems similar to our new one at the level of live morphology. The former can be identified, however, by remarkable cortical granules, conspicuously shorter buccal field (likely,1/6 of cell length) and relatively smaller size (200–300 Mm versus 300–500 Mm) ( Kahl 1932).
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.