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Sculptures by Phyllis Bone


The most important parasites of humans and domestic stock belong to one of three phyla:

  • Phylum Sarcomastigophora
    • Subphylum Sarcodina – amoebae move by processes or pseudopodia.
    • Subphylum Mastigophora –flagellates move by one or more whip-like processes or flagella.
  • Phylum Ciliophora – ciliates move by short hair-like processes or cilia.
  • Phylum Apicomplexa – apicomplexans move by body flexion; all are parasitic, using the apical complex to invade host cells.

These specimens represent the three phyla of parasitic protozoa:

Clockwise from top left:

Amobae of Entamoeba histolytica, the cause of amoebic dysentery in humans;

Trypanosoma brucei, a flagellate protozoan causing sleeping sickness in humans;

Balantidium coli, a usually harmless ciliate parasite of the intestine of pigs;

Symbiotic ciliates from the rumen of cattle: one species is completely covered with cilia; the other is naked except for a crown of cilia at the anterior end of the organisms;

Babesia sp., an apicomplexan parasite in the red blood cells of an African lion.