Parauronema cf. longum Song, 1995

The morphological characters of parasitic Parauronema cf. longum correspond well with free-living P. longum except the body size (60–85 × 25–35 μm in vivo in parasitic forms vs 30–55 × 12–25 μm in in free-living forms), proportion of buccal field length to body length (35–40% in parasitic forms vs almost 50% in free-living forms) and extrusomes (present in parasitic forms vs absent in free-living forms) (Song 1995). Characters of larger body size and smaller cytostome may be consistent with its parasitic life-style.