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BIO 224 Invertebrate Zoology The Protozoans Defining Characteristics: 1) All are unicellular eukaryotes lacking collagen and chitinous cell walls (simple colonies may occur in some groups); 2) All are non-photosynthetic in the primitive condition (photosynthesis has been acquired secondarily in several groups)

Figure 3.1. Current taxonomic placement of “Protozoan” groups based upon molecular and ultrastructural data. (see Box 3A pg 61, Brusca et al.) I. Alveolata (or Chromoalveolata) Phylum Ciliophora

Paramecium Stentor

Vorticella Euplotes

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Phylum Dinozoa Phylum Apicomplexa Apicomplexans have an apical complex composed of apical ring of microtubules, rhoptries (three underneath or underbrush), micronemes (thread), and longitudinal microtubules. Some apicomplexans lack mitochondria. Apicomplexans include Plasmodium vivax and P. falciparum plus two other species that cause Malaria in humans. There are about 50 species in the genus Plasmodium that infect other mammals. Toxoplasma gondii is another apicomplexan that infects cats and that can kill an unborn human fetus. Infection is usually picked up from cat feces.

Ceratium Noctiluca

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II. Excavata Phylum Euglenozoa (including Kinetoplastida) Phylum Heterolobosea Giardia lamblia Naegleria fowleri Phylum Parabasala

Euglena

Trypanosoma

Trichonympha

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III. Amoebozoa (have pseudopodia) Amoeba Difflugia Arcella

IV. Rhizaria Phylum Foraminifera (or Granuloreticulosa) Phylum Radiolaria

Globigerina Acanthometra V. Opisthokonta Proterospongia (colonial) Solitary choanoflagellate

F 2016