THE PSEUDOCOELOMATE BODY PLAN

BODY CAVITIES

• coelom: tube within a tube; body cavity.

Pseudocoelomates (aschelminths) - 7 phyla [Fig. 20.3]

• Learn about pseudocoelomates from the University of California Museum of Paleontology website
• body cavity between mesoderm and endoderm [fig 16.11b]
• hydrostatic skeleton, complete digestive tract in most, etc.
• eutely: Caenorhabditis elegans [Box 20.1] . The Riddle lab presents a good introduction to this species of roundworm.

PHYLUM ROTIFERA: 2,000 spp.

Learn more about rotifers from Wim von Egmond.

Or look at and learn about  rotifers from Central Texas from Jerry Evans

• Characteristics [Fig. 20.4]
  1. morphology
  2. parthenogenesis [Fig. 20.5]

PHYLUM NEMATODA - roundworms

• 16,000 named species - 500,000 possible species

Learn about roundworms from the University of Michigan Museum of Zoology website.

This site from Jim McCarter  has links to everything you could ever possibly want to know about roundworms.

• Chararacteristics
  1. morphology
  2. ecology
  3. reproduction
• free living
  • Anguillula: the vinegar eel
  Caenorhabditis: a soil nematode
• parasites
  1. Ascaris lumbricoides: giant intestinal roundworm [Fig. 20.10]
     • information from Parasites and Parasitological Resources at Ohio State
  2. Enterobius [Fig. 20.11]: pinworms
     • information from Parasites and Parasitological Resources at Ohio State
     • how to check for pinworms
  3. Necator [Fig. 20.12]: hookworms
     • information from Parasites and Parasitological Resources at Ohio State
  4. Tricinella [Fig. 20.13]: trichinosis
     • information from Parasites and Parasitological Resources at Ohio State
  5. Wuchereria: filarial worms [Fig. 20.14-20.15]
     • elephantiasis
       • information from Parasites and Parasitological Resources at Ohio State
     • information from the World Health Organization

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