Metanophrys sinensis Song & Wilbert, 2000

Pan, Xuming, Fan, Xinpeng, Gao, Shan & Chen, Ying, 2016, Taxonomy and morphology of four “ ophrys-related ” scuticociliates (Protista, Ciliophora, Scuticociliatia), with the description of a new genus, Paramesanophrys gen. nov., European Journal of Taxonomy 191, pp. 1-18 : 10

Metanophrys sinensis Song & Wilbert, 2000

Figs 4E , 6 ; Table 2

This species was described by Song & Wilbert (2000) in detail based on their Qingdao population. In the current work, it is reported for the first time from South China Sea. An improved diagnosis is provided herein based on all these data; the improved parts are highlighted in bold.

Improved diagnosis

Slender to elongated oval body shape; in vivo about 25–50 × 10–20 µm with pointed anterior end; buccal field about 30%–50% of body length; mostly ten somatic kineties, of which somatic kinety 1 consists of c. 35 basal pairs; M1 composed of two rows, each with 7–10 kinetosomes, longer than M2; two-rowed M2; contractile vacuole pore located near posterior end of kinety 2; extrusomes present; marine habitat.

Description of Zhanjiang population

Body 25–30 × 10–15 µm in vivo, usually elongate-oval in outline, with anterior end distinctly pointed and posterior rounded ( Fig. 6 A–B). Body asymmetrical in outline when viewed ventrally, with anterior end slightly curved sideways ( Fig. 6 A–B). Ventral side almost straight, while dorsal side convex. Buccal field 2/5 to ½ of body length, with cytostome located anterior to equatorial plane of body ( Fig. 6C ). Cilia densely packed, about 7–8 µm long. Caudal cilium about 15 µm in length ( Fig. 6B ). Pellicle thin and slightly notched, with extrusomes about 2–3 µm long and dense beneath cortex ( Fig. 6D ). Endoplasm colourless to greyish, containing several food vacuoles and bar- or dumbbell-like crystals, which are usually 3 µm long and located in anterior and posterior regions of body ( Fig. 6 A–B, G). One large round to oval macronucleus approximately centrally located, with many small, irregularly shaped nucleoli on surface. Contractile vacuole about 5 µm in diameter and caudally positioned near ventral side ( Fig. 6B ). Movement with no special features, including swimming moderately fast, sometimes continuously swimming in water without pause.

Ten somatic kineties arranged longitudinally, and dikinetids about ¾ of length of each in anterior part ( Fig. 6J ). Buccal apparatus consists of three Parauronema -like membranelles ( Fig. 6 E–F). M1 slightly below apex and composed of two rows of kinetids with 7–10 basal bodies each, and longer than M2. M2 two-rowed, containing about five basal bodies in each row. M3 located close to M2, normally with three short, obliquely arranged rows of basal bodies. Scutica Y-shaped, with several pairs of kinetosomes ( Fig. 6I ). Silverline system in quadrangular mesh-pattern ( Fig. 6H ). Contractile vacuole pore located near posterior end of kinety 2.

Ecological features

Salinity 21‰, pH 7.3 and water temperature 26 °C.

Figures

Fig. 4. Comparisons among different buccal apparatus patterns of Paramesanophrys gen. nov. and some related genera; arrows in A–J show different positions to which PM extends anteriorly and highlighted structures in A–J mark M2. A. Paramesanophrys typica gen. et sp. nov. (from the present work). B. Mesanophrys carcini (Grolière & Léglise, 1977) Small & Lynn in Aescht, 2001 (from Song & Wilbert 2000). C. Uronema marinum Dujardin, 1841 (from Song et al. 2009). D. Uronemella filificum (Kahl, 1931) Song & Wilbert, 2002 (from Song & Wilbert 2002). E. Metanophrys sinensis Song & Wilbert, 2000 (from Song & Wilbert 2000). F. Anophryoides haemophila Cawthorn et al., 1996 (from Cawthorn et al. 1996). G. Philasterides armatalis Song, 2000 (from Song 2000). H. Paranophrys marina Thompson & Berger, 1965 (from Song et al. 2002). I. Paralembus digitiformis Kahl, 1931 (from Song & Wilbert 2000). J. Cohnilembus verminus (Müller, 1786) Kahl, 1933 (from Song 2000). Abbreviations: M1–3 = membranelles 1, 2 and 3; PM = paroral membrane; Sc = scutica.

Fig. 6. Metanophrys sinensis Song & Wilbert, 2000, in vivo (A–D, G) and after protargol (E–F, I–J) or silver nitrate (H) staining. A. Ventral view of a typical individual. B. Ventral view of another individual; arrowheads mark somatic cilia. C. Ventral view; arrowhead exhibits buccal field. D. Notched pellicle (arrowhead). E. Detailed structure of buccal area. F. Individual in morphogenesis, to show buccal apparatus. G. Ventral view, showing bar-shaped crystal (arrowhead). H. Detail of somatic kinetids. I. Dikinetids of scutica (arrowheads). J. Posterior region; arrowheads show monokinetids of somatic kineties. Abbreviations: M1–3 = membranelles 1, 2 and 3; PM = paroral membrane. Scale bars: A–B = 15 μm.