Uronema marinum Dujardin, 1841

Xuming Pan, 2016, Seven scuticociliates (Protozoa, Ciliophora) from Alabama, USA, with descriptions of two parasitic species isolated from a freshwater mussel Potamilus purpuratus, European Journal of Taxonomy 249, pp. 1-19 : 8

Uronema marinum Dujardin, 1841

Fig. 4 F–I; Table 1

Description

Description based on Alabama population: Size in vivo 10–25 × 6–10 μm, elongate-elliptical in outline ( Fig. 4 F). Anterior end flat, with an apical plate, dorsal posterior area slightly rounded ( Fig. 4 F–H). Buccal field 50% of body length. Pellicle smooth ( Fig. 4 F–I). Extrusomes approximately 1 µm long, rodshaped, closely beneath pellicle. One large globular to ellipsoidal macronucleus centrally located with numerous tiny (approximately 1×1 μm) irregularly-shaped peripheral nucleoli ( Fig. 4 F–I). Contractile vacuole about 3 μm in diameter at posterior end of cell ( Fig. 4 H). Movement unremarkable, either swimming continuously or resting on the bottom. Twelve to 13 ciliary rows. Buccal apparatus typical of genus: M1 positioned near apical plate and composed of 5–7 kinetosomes; M2 slightly longer than M1; M3 very short ( Fig. 4 I). PM on right of shallow buccal cavity, composed zigzaging row of basal bodies, extending anteriorly to middle of M2 ( Fig. 3 I).

Figures

Fig. 3. A – D. Pseudocohnilembus hargisi Evans & Thompson, 1964. E – J. Parauronema cf. longum Song, 1995. A – C, E – I. In vivo. D, J. After silver impregnation. A, E. Ventral views of typical individuals, arrow in (A) shows caudal cilia. B – C, F – G. Different individuals, showing varying body shapes, arrowheads in (F) mark somatic kineties. D, J. Detailed structure of the buccal area. H. Ventral view, arrow refers to dumbbell-shaped crystals. I. Posterior end, arrow marks caudal cilium. Abbreviations: M 1, 2, 3 = membranelle 1, 2 and 3; PM = paroral membrane; Sc = scutica. Scale bars: A – B = 15 μm; C, E = 40 μm; G = 60 μm.

Fig. 4. A – E. Uronemita filificum Kahl, 1931. F – I. Uronema marinum Dujardin, 1841. J – N. Pleuronema setigerum Calkins, 1902. A – C, F – H, J – L. In vivo. D – E, M – N. After silver impregnation. A, F, J. Ventral views of typical individuals. B – C, G – H, K – L. Different individuals, showing variation in body shape, arrow in (B) shows the conspicuous apical plate, arrows in (C, H) mark contractile vacuoles. D, I, M – N. Detailed structures of buccal area, arrow in (M) indicates the ring-like posterior end of M 2 a, arrowheads in (M) mark preoral kineties. E. Ventral view, arrowheads show somatic kineties. Abbreviations: M 1, 2, 3 = membranelle 1, 2 and 3; M 2 a = the anterior part of membranelle 2; M 2 b = the posterior part of membranelle 2; Ma = macronucleus; PM = paroral membrane. Scale bars: A – B = 20 μm; F, H, N = 10 μm; G = 5 μm, J – L = 30 μm.