Genus: Cigar- or foot-shaped; a single macronucleus and 1 to several vesicular or compact microuclei (Kudo, 1966).
Species: 180-300 μm long; a compact micronucleus; two contractile vacuoles (Kudo, 1966). Cylindrical or cigar-shaped; rounded anteriorly, pointed posteriorly; one large compact micronucleus ("caudatum" group) approximately 8 μm diam.; two contractile vacuoles; 170-290 μm long (Wichterman, 1986). Elongate, rounded anteriorly, pointed posteriorly; caudal cilia present; 180-280 μm long; a single macronucleus with a single micronucleus; two contractile vacuoles (Carey, 1992).

Vegetative cells
intact cells by H. Horikami by Y. Tsukii	intact cells by A. Yanagi by K. Mikami	Food-vacuole formation	Food-vacuole formation
Azure C staining	Azure C staining	Cell division	Silver-stained
Sexual reproduction
mating reaction	holdfast union	paroral union	meiosis
nuclear events by K. Mikami	micronuclear process by A. Yanagi	behavior of micronuclei by A. Yanagi	nuclear exchange by A. Yanagi
Conjugating pair 2n x 0	heat shock by M. Takahashi	Schemes of conjugation	Autogamy induced by methyl urea by A. Yanagi
Organelle / Inclusions
trichocysts	mitochondria	inclusion bodies
DNAs
mtDNA trees/protocol	mtDNA RFLP	mt Plasmids Gel	mt Plasmids RAPD
RAPD patterns of macronuclear genomes
Series Old RFLP	Series New RFLP	Series II RFLP	Series III RFLP