Topic #2: Cnidarian Phylogeny Based on rRNA

• Cnidarian Phylogeny Based on rRNA:

  A) Protostomia

  B) Deuterostomia

  C) Hexacorallia

  D) Octocorallia

  E) Hydrozoa

  F) Cubozoa

  G) Scyphozoa

  H) Staurozoa

  I) Bilateria

  J) Anthozoa

  K) Medusozoa

  
• Class Anthozoa

  • Includes Subclass Hexacorallia and Subclass Octocorallia in which their prefixes indicate the number of Mesenteries
• Mesentery

  • coelom the divides gastrovascular cavity into compartments
• Number of Mesentery:

  Hexacorallia = 6 mesenteries

  Octocorallia = 8 mesenteries
• Class Medusozoa

  • Includes Subclasses: Hydrozoa, Cubozoa, Scyphozoa, Staurozoa
• Subclass Staurozoa used to be an Order under Scyphozoa
• Cubozoa, Scyphozoa, and Staurozoa are the true jellyfishes