Table 1.

Giardia species

Species nameHostsMorphology by:Molecular data
Light microscopyElectron microscopy
G. agilisAmphibiansLong and slender; teardrop-shaped median bodyNAa
G. murisRodentsShort and rounded; small rounded median bodyDistant from G. lamblia
G. lambliaNumerous mammals, including humansPear shaped; one or two transverse, claw-shaped median bodiesClade with multiple genotypes
G. ardeaeHeronsSame as G. lambliaVentral disk and caudal flagellum similar toG. murisCloser to G. lamblia than toG. muris
G. psittaciPsittacine birdsSame as G. lambliaIncomplete ventrolateral flange, no marginal grooveNA
G. microtiVoles and muskratsSame as G. lambliaCysts contain two trophozoites with mature ventral disksSimilar to G. lamblia genotypes
  • a NA, not available.