Orthoamphisiella
Orthoamphisiella Eigner & Foissner, 1991 (ref. ID; 7423)
Family Orthoamphisiellidae (ref. ID; 7423)
- Orthoamphisiella franzi (Foissner, 1982) Eigner, 1995 (ref. ID; 7423)
Basionym; Gonostomum franzi (ref. ID; 7423); Kahliella franzi (ref. ID; 7423)
- Orthoamphisiella grelli Eigner & Foissner, 1993 (ref. ID; 4832 original paper, 7423) reported author and year? (ref. ID; 191)
- Orthoamphisiella stramenticola Eigner & Foissner, 1991 (ref. ID; 4832, 7423) reported author and year? (ref. ID; 191)
Basionym
Gonostomum franzi (ref. ID; 7423); Kahliella franzi (ref. ID; 7423)
Descriptions
Number of long cirral rows reduced; the rightmost row six can be considered as right marginal rows. At least three enlarged frontal cirri. Three dorsal kineties built by pairs of basal bodies. (ref. ID; 7423)
Orthoamphisiella grelli Eigner & Foissner, 1993 (ref. ID; 4832 original paper, 7423) reported author and year? (ref. ID; 191)
Diagnosis
Size in vivo 60-90x20-30 um. 2 macronuclear segments, 20 adoral membranelles, 2 buccal cirri at anterior end of endoral membrane and 7 fronto-ventral cirri in 2-3 short rows on average. (ref. ID; 4832)
Descriptions
Long-elliptical, right body margin straight to slightly concave, left more or less convex. Anterior and posterior end slightly tapered. Dorso-ventrally inconspicuously flattened; highly flexible. Macronuclear segments ellipsoid, in vivo about 15x6 um, left of cell median. Usually 2-3 micronuclei attached to macronuclear segments, in vivo about 3 um in diameter. Contractile vacuole near left margin in mid-body, with 2 inconspicuous collecting canals. No cortical granules or cytoplasmic crystals. Cytoplasm with some fatty globules 2-4 um in diameter and many small food vacuoles 4-7 um in diameter containing bacteria and heterotrophic flagellates. Adoral zone of membranelles 30% of body length, commences in median of cell, i.e. at level of second frontal cirrus. Oral lip extends lid-like across buccal cavity. Paroral membrane straight, inserted in shallow fold on outer surface of lip, parallel to oblique left edge of anterior portion of oral lip. Endoral membrane slightly curved, inserted on right inner surface of buccal cavity. All cirri about 10 um long. Right marginal row commences at level of 2nd-3rd cirrus of long ventral row, curves subterminally to median of cell, regularly terminating slightly above left marginal row. Long ventral (median) row commences at distal end of adoral zone of membranelles and usually extends to centre of ventral surface. Uppermost (frontal) 3 cirri distinctly enlarged. Buccal cirri in line with 2nd a frontal cirrus. Fronto-ventral row 1 in line with 3rd frontal cirrus. Dorsal cilia in vivo 3 um, arranged in 2 rows almost as long as cell. Caudal and transverse cirri absent. (ref. ID; 4832)
Division morphogenesis: Divisional morphogenesis in O. grelli is very similar to that of O. stramenticola. However, the primordium for the long ventral row develops more anteriad, leaving only 3-7 (average=4.5; n=6) parental cirri intact. Orthoamphisiella stramenticola, in contrast, has this anlage in the centre of the long ventral row. Thus, 9-14 (average=11.6; n=18) parental cirri remain or are renewed in post-dividers. (ref. ID; 4832)
Comparison with related species
Orthoamphisiella grelli differs from the only congener, O. stramenticola, mainly in the number of macronuclear segments (4 in O. stramenticola). Minor differences concern the number and location of the buccal cirri and the body size. (ref. ID; 4832)
Etymology
This new species is named in honour of Professor Dr. Karl G. Grell (Tubingen, a tireless and successful investigator of marine and freshwater protists. (ref. ID; 4832)
Type location
In moss and soil from a river bank on Gough Island, Transvaal Bay (W10 degrees 00', S40 degrees 20'). (ref. ID; 4832)
Type specimens
A holotype and a paratype of O. grelli as 2 slides of protargol impregnated cells have been deposited in the collection of microscopic slides of the Oberosterreichisches Landesmuseum in Linz. (ref. ID; 4832)
Orthoamphisiella stramenticola Eigner & Foissner, 1991 (ref. ID; 4832, 7423) reported author and year? (ref. ID; 191)
Descriptions
Japanese population: Size in vivo about 90x30 um. Elliptical, right body margin slightly concave, left convex and slightly indented beneath adoral zone of membranelles. Posterior end slightly narrowed, both ends broadly rounded. Contractile vacuole in mid-body and with collecting canal. No cortical granules; loosely arranged, inconspicuous subpellicular granules were erroneously reported for the type population (Eigner & Foissner 1991). A reinvestigation of material from the type location showed that these were actually mitochondria. Cytoplasm contains many colourless, fatty globules, 1-3 um in diameter. Food vacuoles filled with fungal spores and filamentous and coccal (c. 4x3 um) cyanobacteria. Adoral zone of membranelles 35% of body length, bases of membranelles 7 um in vivo. Oral lip extends lid-like across buccal cavity. Paroral membrane inserted in small fold on outer surface of lip, alongside more or less oblique left edge of anterior portion of oral lip. Endoral membrane slightly curved, on right inner surface of buccal cavity. All cirri c. 10 um long. Right marginal row commencing on a level with 4th-6th cirrus or long ventral row, curves subterminally to median of cell almost contacting left marginal row. Long, rightmost ventral (median) row commences at distal end of adoral zone of membranelles and extends to centre of ventral surface. Buccal cirri almost in line with 2nd frontal cirrus. Fronto-ventral row 1 in line with 3rd frontal cirrus. A third short fronto-ventral row is absent, whereas it is present in 64% of the type population individuals. Dorsal cilia in vivo 3 um long, arranged in 2 kineties. Caudal and transverse cirri absent. The type population has a mean of 23 cirri in the long ventral (median) row. The specimens used in this study, although originating from the type location, have 28 cirri (Min=26; Max=32; n=12). This may be due to cloning of the (first) type population, whereas specimens from a raw culture were used in this study. (ref. ID; 4832)
Divisional morphogenesis: The nuclear apparatus and the marginal rows divide in the usual way. The dorsal infraciliature develops according to type I (Foissner & Adam 1983). No caudal cirri are formed. These processes therefore require no further comment. (ref. ID; 4832)
- Stage 1. Stomatogenesis commences with the proliferation of basal bodies to form a narrow anarchic field near the open ends of the high and left marginal row.
- Stage 2. The oral primordium grows to a large field of loosely arranged basal bodies extending between the adoral zone of membranelles and the posterior end of the cell. The posterior cirri of the 1st fronto-ventral row disaggregate to a short streak.
- Stage 3. The posterior portion of the oral primordium narrows, the anterior portion differentiates adoral membranelles. The 1st fronto-ventral row disorganizes completely and forms a long streak of basal bodies. Likewise, the buccal cirri diaggregate to a long streak of basal bodies (anlage 2 generating middle frontal cirrus and buccal cirri of proter and opisthe, respectively). The 2nd and 3rd fronto-ventral row also disaggregate and form short streaks of basal bodies (anlagen 4 and 5 for 2nd and 3rd fronto-ventral row of proter and opisthe, respectively).
- Stage 4. Right of the developing adoral membranelles a streak of basal bodies separates from the oral primordium generating the 1st frontal cirrus and the undulating membranes for the opisthe. The proter's anlagen 2-5 split and their posterior portions migrate posteriad; the anterior ends of the anterior portions develop frontal cirri. The parental undulating membranes disaggregate forming the 1st frontal cirrus and single, long and narrow streak of basal bodies. An anlage develops within the middle portion of the long ventral (median) row. The splitting of this anlage occurred slightly earlier in the Austrian population than in the Japanese one. At this stage six anlagen are thus recognizable for each the proter and the opisthe. Individuals having only 2 short fronto-ventral rows possess five anlagen each.
- Stage 5. The formation of the opisthe's adoral membranelles is complete. The anlagen for the undulating membranes are long, single streaks of basal bodies in both proter and opisthe. The fronto-ventral anlagen have organized to cirri.
- Stage 6. The anlagen for the undulating membranes split in both proter and opisthe to form the endoral and paroral membrane. The anlage within the long ventral row proliferates 28 cirri in the opisthe from disaggregated parental cirri, i.e. all cirri are new. In contrast, only 19 cirri (average=19.3; n=6) are formed in the proter; 11 parental cirri (average=11.6; n=18) remain or are renewed in post-dividers. (ref. ID; 4832)