Fuscheria terricola BERGER, FOISSNER & ADAM, 1983

Vďačný, P., 2007, Morphological variation of Fuscheria terricola BERGER et al., 1983 (Ciliophora, Haptoria), Linzer biologische Beiträge 39 (2), pp. 1239-1248 : 1240-1245

Fuscheria terricola BERGER, FOISSNER & ADAM, 1983

1983 Fuscheria terricola BERGER, FOISSNER & ADAM, J. Protozool. 30: 529 (original description; description of ontogenesis).

1988 Fuscheria terricola BERGER et al., 1983 – FOISSNER & FOISSNER, Arch. Protistenk. 135: 213-235 (description of fine structures; revision of haptorids).

2002 Fuscheria terricola BERGER et al., 1983 – FOISSNER et al., Denisia 5: 191 (description of a Namibian population with short extrusomes).

M a t e r i a l: This species was studied in two populations, namely from Jakubovské rybníky (pond dam) and Suchohrad (hard-meadow forest). The later population matches the original description very well in the main taxonomical features and is thus described very briefly. Since the isolate from Jakubovské rybníky differs in several taxonomical features such as the fine structure of the dorsal brush and the number of the micronuclei, it is described in detail.

Morphological description of Jakubovské rybníky popula- t i o n: Size about 60-90 × 25-45 µm, usually about 80 × 35 µm in vivo. Outline elliptical or slightly asymmetrical, length:width ratio about 2.4:1 on average in protargol preparations, posterior body end more broadly rounded than the anterior one ( Fig. 1 ). Macronucleus in mid-body or slightly below it, U-shaped ( Figs 4, 5 , 13-17 ), rarely Jshaped ( Figs 11, 18, 20 ), with globular nucleoli. Micronucleus globular, about 3.4 µm across, near macronucleus; out of 28 protargol-impregnated specimens only two

Measurements in µm. Data based on randomly selected protargol-impregnated specimens from non-flooded Petri dish culture. CV – coefficient of variation in %, M – median, Max – maximum, Mean – arithmetic mean, Min – minimum, n – number of individuals investigated, SD – standard deviation, SE – standard error of arithmetic mean.

possessed 2 micronuclei ( Fig. 19 ) and one had 3 micronuclei. Extrusomes arranged centrally in oral bulge, nail-shaped and 4-6.5 µm long ( Figs 7, 9 ). Many developing extrusomes scattered in cytoplasm, fusiform, clavate or rod-like after protargol impregnation ( Figs 11, 13 ).

Cilia about 7 µm long in vivo, rather widely spaced, that is, on average 43 ciliated kinetids in an ordinary kinety; arranged in 17 longitudinal, equidistant rows commencing underneath circumoral kinety and extending to posterior polar area ( Figs 2, 3 , 11-14 ). Dorsal brush two-rowed, occupies about 14% of body length; dikinetidal portion of row 1 slightly longer than portion of row 2 ( Table 1). Row 1 on average 10.1 µm long, composed of on average of 13.2 dikinetids associated with clavate anterior bristles gradually increasing in length from 3 µm anteriorly to 4.5 µm in half of brush length and rodshaped posterior bristles (0.5 µm long). Brush row 2 usually commences with 1-2 monokinetids, 8.4 µm long on average, individual dikinetids associated with ellipsoidal anterior bristles of uniform length (3 µm) and conspicuously shorter (0.5 µm long) rodshaped posterior bristles ( Fig. 6 ); continues posteriorly with monokinetidal bristle tail extending to mid-body having ellipsoidal bristles, about 3 µm long ( Figs 1, 8 ).

Oral apparatus apical, oral bulge ring-shaped and inconspicuous because only 5.5 µm wide and 2 µm high in vivo, mouth centre slightly depressed. Circumoral kinety at base of oral bulge, composed of rather widely spaced dikinetids at the top of each ciliary row ( Figs 2, 3 , 11-14 ). Nematodesmata originate from circumoral basal bodies and 4-11 ciliated basal bodies in anterior region of all somatic kineties (oralized somatic kinetids); oral basket inconspicuous in vivo as composed of small bundles ( Fig. 8 ).

N o t e s o n m o r p h o l o g y o f S u c h o h r a d p o p u l a t i o n: Size about 90 × 40 µm, length:width ratio 2.2: 1 in protargol preparations. Macronucleus ellipsoidal, typically accompanied by single micronucleus about 2.7 µm across. Extrusomes nailshaped, only distal portion impregnated with protargol, about 5 µm long. On average 15 somatic ciliary rows. Dense group of on average 7 kinetosomes in anterior part of second somatic kinety left of brush row 2 ( Figs 23, 24, 28 ). Two ciliary rows anteriorly differentiated to dorsal brush: brush row 1 with about 8 dikinetids; brush row 2 with 4 dikinetids. Both rows with same bristle composition, that is, dorsal bristles of uniform length and shape. Row 2 continues posteriorly with monokinetidal tail extending to mid-body ( Fig. 22 ).

Figures

Figs 1-10: Fuscheria terricola (Jakubovské rybníky population) from life (1, 4-10) and after protargol impregnation (2, 3). 1: Left side view of a representative specimen. 2, 3: Ciliary pattern of dorsal and ventral side and nuclear apparatus. 4, 5: Lateral views showing variants of body shape and nuclear pattern. 6: Structure of dorsal brush. 7: Oral bulge extrusomes are nail-shaped, 4-6.5 µm long. 8: Anterior body portion. 9: Frontal view of oral bulge filled with extrusomes. 10: Surface view showing cortical granulation. CG – cortical granules, CV – contractile vacuole, B2 – dorsal brush row 2, Ex – extrusomes, MA – macronucleus, MT – monokinetidal bristle tail of brush row 2, N – nematodesmata, OB – oral bulge, SK – somatic kinety. Scale bars 30 µm.

Figs 11-21: Fuscheria terricola (Jakubovské rybníky population). 11, 13, 14: Ciliary pattern of dorsal side and nuclear pattern. 12: Ciliary pattern of ventral side. 15-21: Lateral views showing variants of body shape and some observed shape and patterns of macro- and micronuclei location. CK – circumoral kinety, CV – contractile vacuole, Ex – extrusome, B1, B2 – dorsal brush row 1 and 2, N – nematodesmata. Scale bars 20 µm.

Figs 22-30: Fuscheria terricola from several populations. 22: Left side view of a representative specimen from Suchohrad population. 23, 24: Ciliary pattern of dorsal and ventral side of Suchohrad population specimen. 25-27: Specimen from type, Salzburg (from BERGER et al. 1983) and Namibian population (from Foissner et al. 2002). 28: Specimen after protargol preparation from Suchohrad population. 29, 30: Specimen after protargol preparation from Jakubovské rybníky population. B1 – dorsal brush row 1, Ex – extrusomes, N – nematodesmata, SK – somatic kinety. Scale bars 30 µm.