Intro to Cnidarians Flashcards
Cnidarian Chacteristics
Have Cnidae(nematocyst). Tend to form colonies, alternation of generations. Also have a gastrovascular cavity. Myoepithelial cells, radial symmetry, and are diploblastic with simple nerve net and planula larvae
special cells of cnidarians
Have myoepithelial cells,amoeboid cells, and Cnidocytes
Chatcteristics of Subphylum Anthozoa
are only polyps, cnidae are in the epi or endodermis, have tenticles in multiples of 8, or 6, all are marine.
Characteristics of Subclass Hexacorallia
simple tentacles, paired mesenteries, have skeleton of calcareous, or chitinous.
Order Actiniaria
Solitary polyps, with no solid skeleton, typically have 2 Siphonoglyphs also have zooxanthellae(dinoflagelllates)
Order Ceriantharia
Sand anemones
Order Zoanthidea
Colonial Anemones
Order Antipatharia
Black Coral
Order Scleractinian
Hard Corals, are mostly colonial, half of them associate with zooxanthelae. Lack Siphonoglyphs, and have Calcareous exoskeletons. Polyps sit in pits called calices.
Lophelia pertusa
Deep sea coral in the Atlantic and Caribbean. Threatened.
Subclass Octocorallia
Polyps with 8 Pinnate tentacles. Have polyps with 8 complete mesenteries, and each have a single siphonoglyph. They can be free or fused calcareous sclerites in mesenchyme
Order Alcyonacea
soft gorgonians, sclerites free in the coenchyme.
Suborder Stolonifera
Polyps arise from a ribon like stolon
Subclass Octocorallia
Have tall branching colonies of alternating terminal and daughter polyps.
Order Pennatulacea
Have adapted to live in soft sediments, with polymorphic polyps. Axial polyps with peduncle buds other than pollps
