Sultanophrys
Sultanophrys Foissner & AL-Rasheid, 1999 (ref. ID; 2859 original paper)
[ref. ID; 2859]
Sultanophrys has two unique features, namely, an anterior secant system at the right side of the glabrous stripe and a lateral kinety at the left. Both characters are easy to recognise in well-impregnated specimens. (ref. ID; 2859)
Etymology; The name is a composite of the Anglo-French word Sultan (Prince, Sovereign) and the Greek noun phrya (eyelash ~ cilium ~ ciliate sensu lato), meaning "the Prince's ciliate". Feminine gender. (ref. ID; 2859)
- Sultanophrys arabica Foissner & AL-Rasheid, 1999 (ref. ID; 2855, 2859 original paper, 7488)
Sultanophrys arabica Foissner & AL-Rasheid, 1999 (ref. ID; 2855, 2859 original paper, 7488)
Diagnosis
Extended cells in vivo about 780x70 um and flattened ribbon-like, contract slowly to about half of body length. Head, neck, and tail indistinctly set off from trunk. 31 macronuclear nodules and 12 micronuclei on average form distinct strand in middle third of body. On average 35 ciliary rows on right side of cell; left unciliated, except for bristle kinety, glabrous stripe thus as wide as trunk and tuberculate in fully contracted specimens. Head dark due to accumulation of cytoplasmic inclusions and brilliant brown cortical granules in oral bulge and bowl-shaped oral cavity; circumoral kinety interrupted by indistinct cleft containing 3 brosse kineties on average. Cells dark and punctate due to two types of cortical granules (extrusomes?): large granules about 2 um across, brilliant brown, in single row between each two kineties and irregularly distributed in cortex of glabrous stripe; small granules about 0.2 um across, citrine, densely and irregularly arranged. (ref. ID; 2859)
Descriptions
In vivo, the organisms is about 800 um long, 70 um wide, distinctly flattened, and can contract up to half the body length. On the right side are about 34 longitudinal ciliary rows, while the left is barren except for the bristle kinety, which borders the barren area, the so-called glabrous stripe. At the right side of the glabrous stripe are several shortened kineties, which abut to the bristle kinety forming the anterior and posterior secant system. Furthermore, there is a special (lateral) kinety between the left branch of the bristle kinety and the first ordinary ciliary row. The lateral kinety shows various specialisations, most notable subcortical fibres forming long bundles in the posterior region of the cell. The cylindrical apical end (head) contains distinct oral structures consisting of a circumoral ciliary row and, in midline of left side, a brosse composed of three minute, oblique kineties. (ref. ID; 2855)
[ref. ID; 2859]
Very flexible and thus usually curved and spirally twisted along main body axis, producing bright stripe under transmitted light; occasionally even coiled up. Glides and winds moderately fast on and between organic debris. Body of almost same width in anterior three quarters of cell, head and neck thus indistinctly set off from trunk; posterior quarter gradually narrowed forming short, blunt tail curved to left when cell is viewed from right side. Head indistinctly set off from broad neck, dark due to accumulation of cytoplasmic granules, not fragile; head margin at left side of cell thickened due to encroaching somatic kineties of right side, produce distinct postoral depression appearing, under transmitted light, as bright patch between brosse and bulging glabrous stripe. Oral bulge conspicuous, although not projecting above body proper, because packed with brilliant brown granules described below, interrupted at brosse site. Specimens dark and opaque in dissecting microscope, punctate under transmitted light at low magnification (< /_ x100) due to large, brown cortical granules. Contracts slowly and not very extensively, that is, up to half of body length, prepared specimens thus about 400 um long. Fully contracted cells banana-shaped, convex glabrous side distinctly protruding and often conspicuously tuberculate; frequently partially contracted for long periods and then easily mistaken as extended. Postdividers about half as long as morphostatic specimens, flask-shaped with rear end narrowly to broadly rounded. Macronuclear nodules globular to slightly ellipsoidal, number highly variable, form long strand in middle third of cell; occasionally some nodules scattered throughout body or, if many are present, arranged side by side producing two indistinct rows. Nodules no connected or clustered, stand out as bright blisters from opaque cytoplasm under transmitted light, each surrounded by distinct membrane and containing many minute nucleoli. Micronuclei globular to slightly ellipsoidal, near and between macronuclear nodules. No contractile vacuole. Cortex very flexible and thin, not gelatinous, tuberculate in contracted cells, contains two size- and colour-types of granules, which are not extruded when cells are pressed or treated with methyl green-pyronin; both granule types coloured and thus easily recognisable in living cells, impregnate heavily with protargol, large type makes cell's periphery knobby in the light and scanning electron microscope. Large granules 0.8-2.5 um, usually 2 um across, brilliant brown, composed of thick membrane (?) surrounding bright centre, sometimes containing conical structure after silver impregnation, surface smooth in the scanning electron microscope, release brownish fluid and become lighter and wrinkled in dying and dead cells, form complex pattern in cortex: (1) a single loose row of these granules is between each two somatic kineties, except for the neck, where they are lacking; (2) in the cortex of the glabrous stripe and oral cavity, they are irregularly arranged; (3) a single row of narrowly space granules surrounds the glabrous stripe; (4) one or two rows are in the oral bulge, which is thus black at low magnification (< /_ x100). Small cortical granules about 0.2 um across, citrine, stain lilac with methyl green-pyronin, very numerous and irregularly arranged, form citrine transverse lines between kineties in contracted specimens, very likely extrusive because cortex of prepared specimens sometimes studded with minute holes. Cytoplasm colourless or yellowish, contains rather many 2-20 um sized golden and colourless fat globules, small and large food vacuole, and three types of crystal-like inclusions: type 1 numerous about 3x1-2 um, ellipsoidal and moderately refractile, occasionally impregnated with protargol; type 2 mainly in head, 3-4x2-3 um, irregularly shaped and highly refractile; type 3 scattered throughout cytoplasm, 3-4 um across, spherical, composed of concentric layers and thus lithosome-like. Some specimens contain many about 4 um long rods, some with a minute constriction in mid-body, very likely bacteria. Omnivorous, feeds on filamentous cyanobacteria, up to 1 mm long nematodes, rotifers, small nauplii, and various ciliates and flagellates. The prey is ingested through the apical end, which is very flexible and can open widely. (ref. ID; 2859)
- Somatic infraciliature: Sultanophrys arabica has only the right surface ciliated, the left is occupied by the glabrous stripe bordered by the bristle kinety. Cilia are about 10 um long and arranged in longitudinal rows, which are distinctly separate from the circumoral kinety and extend between flat cortical crests. The anterior end of the ciliary rows is distinctly curved to the right and composed of condensed, that is, more narrowly spaced dikinetids. Usually, the curvature and condensation are inconspicuous or even lacking in some kineties. At the right margin of the glabrous stripe are two to four ciliary rows gradually shortened anteriorly and about 20 rows posteriorly. In other words, an anterior and posterior secant system are formed at the right margin of the cell, where some ciliary rows abut to the bristle kinety. Thus, the head, neck and tail have slightly fewer kineties than the trunk. The ciliary rows left of the glabrous stripe are unshortened anteriorly and posteriorly. There is a special ciliary rows, the lateral kinety, between the left branch of the bristle kinety and the first ordinary somatic ciliary row. The lateral kinety shows the following specialisations: (1) the dikinetids have ciliated only the anterior basal body and are usually lighter impregnated than those from ordinary ciliary rows; (2) the kinetids are more narrowly spaced than in the ordinary ciliary rows, except for the posterior quarter, and less obliquely arranged; (3) the subkinetal fibres are lacking; (4) the ciliated anterior basal body of the dikinetids bears a conspicuous (modified subkinetal?) fibre, which is short and close to the kinety axis in the anterior three quarters of the kinety and gradually increases in length posteriorly, where the fibres of several kinetids unite to up to 50 um long, subcortical bundles; and (5) the cortical tubercles between the bristle and lateral kinety have a particular, conical shape. The entire infraciliature consists of ciliated dikinetids, except for the following regions, where only the anterior basal body is ciliated: (1) the curved anterior end of the kineties, (2) the tail, (3) the posterior portion of the secant kineties, and (4) the dikinetids of the lateral kinety. The dikinetids are associated with a short, sharply impregnated subkinetal fibre extending slightly beyond the next dikinetids, and a long postciliary fibre forming a distinct postciliodesma right of the kineties. No oralised somatic dikinetids and no myonemes were recognisable. Whether they are lacking or did not impregnate needs transmission electron microscopic investigations. The glabrous stripe extends along the whole body length and width, except for the head region, where it gradually narrows and deepens to form the postoral depression. It is bordered by the bristle kinety, which consists of dikinetids having about 15 um long, rather stiff cilia. The bristle kinety is easily distinguished from ordinary ciliary rows and the lateral kinety because its dikinetids are more widely spaced, except in the anterior region, and more irregularly arranged, frequently forming short fragments consisting of 2-5 bristles furthermore the kinetids either lack or have very inconspicuous postciliary fibres, too small to be recognised with the light microscope. The subkinetal fibres, in contrast, are well developed and unite to a distinct fibre underneath the left branch of the kinety, while those of the right branch extend straight into the cell. The ciliation of the bristle dikinetids, interspersed by rather many unciliated granules, is as in other trachelocercids, that is, those along the right margin of the glabrous stripe have ciliated posterior basal bodies, whereas the dikinetids along the left stripe margin have ciliated anterior basal bodies; thus, the ciliation of the bristle kinetids is opposed by about 180 degrees where the ends of the kinety abut, that is, subapically at the right margin of the glabrous stripe. (ref. ID; 2859)
- Oral infraciliature: The oral infraciliature of S. arabica consists of a circumoral kinety and a minute brosse, difficult to recognise in living specimens. The circumoral kinety extends in the flat groove separating the oral bulge from the head and is interrupted at the brosse site with ends sometimes indistinctly curved posteriorly. It is composed of a single row of obliquely oriented, very narrowly spaced dikinetids, which have 15 um long cilia and 10-35 um long nematodesmata associated with the posterior basal bodies. The nematodesmata of neighbouring dikinetids unite to small bundles, forming a slightly cone-shaped oral basket; rarely, there are 1-2 dikinetids wide gaps within the kinety. The brosse is in a flat cavity and interrupts the circumoral kinety. It consists of 1-5, usually 3 short, oblique dikinetidal ciliary rows, which have ciliated only the posterior basal bodies. The brosse kineties are associated with conspicuous fibre bundles extending posteriorly. Around the brosse are few to many scattered dikinetids and, at right, usually three short kinetofragments, very likely of oral origin. (ref. ID; 2859)
[ref. ID; 7488]
In vivo, S. arabica is about 800 um long, 700 um wide, and 2:1 flattened. On the right side are about 34 meridional ciliary rows, while the left is barren, except for a row of bristles that borders the barren area, the so-called glabrous strip. Sultanophrys arabica can contract up to half the body length, and the glabrous stripe then shows conspicuous, transverse tuberosities. There are about 31 macronuclear nodules in midline of cell. Cells appear dark at low magnification due to innumerable brilliant brown cortical granules, some of which form a distinct ring in the oral bulge just above the circumoral ciliary row. The flattened apical (oral) end, the head, is about 40x40x20 um and black due to many cytoplasmic granules of different size and shape. The head contains distinct oral structures consisting of a circumoral kinety and, in the midline of the left side, a brosse composed of three minute ciliary rows. About 15 um long fibres (nematodesmal bundles) originate from the circumoral basal body pairs and form an inconspicuous funnel. The apical surface is hemispherically indented to form a distinct oral cavigy. (ref. ID; 7488)
Feeding: Sultanophrys arabica fed while gliding on the sediment surface or the bottom of the culture dish. When sensing a large, slender, moving item, such as a nematode or a Condylostoma, they increased gliding speed to reach it. As soon as the head touched the narrowed prey end, a small portion was ingested. Then the oral bulge expanded to engulf the prey. The ciliate then looked very much like a small snake swallowing a large bird egg, when the prey was voluminous. When a small portion of the prey has been ingested, the trachelocercids stopped moving and contracted rather strongly, as evident from the tuberose glabrous stripe. Even if the prey kept moving and tried to escape, the predator hardly moved. It seems that the internal part of the neck worked like a "glue" to hold the prey during the expansion of the oral bluge. Indeed, when cells were disrupted in this early feeding stage, the ingested prey portion was already embedded in viscous, granular cytoplasm, indicating that digestion had begun during ingestion. The dark accumulation of granules in the oral area (head) and the ring of brilliant brown granules in the oral bulge did not change during feeding. Feeding invariably occurred through the apical end. Depending on the kind of food, the oral cavity opened more or less widely. When prey was large and spreading, for instance nauplii, the oral area may even be damaged, especially at the fragile brosse site, giving the impression of subapical feeding. When prey was lost during cytological preparation, the oral opening remained trumpet-like and expanded. Finally, the prey was surrounded by a large vacuole, which swelled the glabrous stripe and more or less deformed the predator. Feeding on large prey items was a long process while filamentous bacteria, diatoms, and small ciliates were ingested within a few minutes. Swallowing about 300 um long Condylostoma took about 10 min; rotifers and long nematodes took up to 40 min to be fully ingested. Usually, prey become immobile when ingestion began, but some nematodes were still moving when completely ingested and may then heavily deform the predator. (ref. ID; 7488)
Comments
Sultanophrys arabica is a conspicuous species, mainly dye to the cortical granules, which form dense stripes and make cells dark at low magnification. This particular granulation evolved convergently in several genera and species, namely, in Tracheloraphis margaritata, T. grassei, T. poljanskyi, Trachelocerca binucleata, and Kovalevaia sulcata. Tracheloraphis margaritata (Kahl, 1930) Dragesco, 1963 is a difficult species. According to the original description, it is only 350 um long when extended, has a narrow glabrous stripe, and possesses only 5 macronuclear nodules forming a short strand. Later authors, however, identified large (up to 2000 um) trachelocercids with a rather broad glabrous stripe and many (9-101) macronuclear nodules forming a long strand with Kahl's species. Certainly, S. arabica is distinctly different from the original description of T. margaritata, even if the considerable variability trachelocercids generally have is taken into account. The redescriptions mentioned above are more difficult to rate. We checked the protargol slide Dragesco and Dragesco-Kerneis used for the redescription of T. margaritata. Unfortunately, they are of poor quality, hardly showing details of the infraciliature. However, the cortical granule stripes recognisable indicate that the anterior secant system is at the right side, not at the left, as illustrated by Dragesco and Dragesco-Kerneis. Thus, the species investigated by these authors could have been S. arabica. Tracheloraphis grassei (Dragesco, 1960) Foissner and Dragesco, 1996 has large brown granules only on the left side. Furthermore, it has a distinct tail and only about 14 ciliary rows (31-40 in S. arabica). Tracheloraphis poljanskyi (Raikov, 1963) Foissner, 1997 has only about 12 ciliary rows (31-40 in S. arabica) and a long, narrow neck. Trachelocerca binucleata Dragesco, 1960 has only 2 macronuclear nodules and is flask-shaped and only 200 um long. Kovalevaia sulcata (Kovaleva, 1966) Foissner, 1997 has a distinct, obconical head, less than 25 ciliary rows (31-40 in S. arabica) and only 1 brosse kinety (usually 3 in S. arabica) (ref. ID; 2859)
Etymology
Named after the region found. (ref. ID; 2859)
Type location
Brackish coastal pond at Safwa village (50 degrees 06'E, 26 degrees 39'N), Saudi Arabian Gulf coast. (ref. ID; 2859)
Measurements
Many characters are highly variable (coefficient of variation >20%), as is usually in trachelocercids. Fully extended specimens in vivo about 670-900x50-100 um, on average 780x70 um, length:width ratio 8:1-16:1, usually 11:1, that is, stouter than many other large trachelocercids; flattened ribbon-like (2-3:1), including oral area. (ref. ID; 2859)