radiate phyla ii chapter 7. class cubozoa: sea wasps and box jellyfish about 3 dozen species almost...
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Radiate Phyla II
Chapter 7
Class Cubozoa: Sea wasps and box jellyfishAbout 3 dozen species almost all are tropical.
medusa & polyp body forms thick mesoglea
Unfrilled bell margin drawn inward to form a velum-like structure.
Cubozoan Sensory Structures
Sensory structures called rhopalia.
Cubozoan Sensory Structures
cubozoans have eyes.
The larger regions actually contain lenses, corneas, and retinas.
Nematocysts are concentrated in rings on the tentacles of cubozoans.
Predominantly two species responsible
• The Box Jelly Chironex fleckeri
• Irukandji Carukia barnesi
The Box Jelly Chironex fleckeri
The Box Jelly Chironex fleckeri
Box Jelly Chironex fleckeri
• Box jellies or sea wasps are thought to be responsible for about 65-100 deaths over the past 50 years in Australia.
• The tentacles can be up to 10 feet long.
• In Australia twice as many people die annually from box jellies as from sharks.
• The toxin of most cubomedusan jellies is more potent than cobra venom.
Irukandji Carukia barnesi
Stings have been recorded from Australia, and a similar syndrome has been described elsewhere in the Pacific.
Every summer, more than sixty people are hospitalized with this potentially fatal syndrome.
Cubozoan Life Cycle
• Similar to jellyfish.
Class Anthozoa
• polyp body form ONLY • all marine
Class Anthozoa
• some are colonial colonies are formed of individual zooids
• some are solitary
Class Anthozoa- life cycle
eggsperm
larva
Sexual reproduction
Class Anthozoa- life cycle
asexual reproduction
fission
pedal laceration
fission
Class Anthozoa
Sea anemones
Class Anthozoa
Soft Corals
Sea pen
Sea pansy
Class Anthozoa
Stony Corals
The Corals
• Make up the largest group of Anthozoa
• Colonial
• Secrete skeleton of calcium carbonate– Cup shaped– Polyp is fixed to this
Theca
Sclerosepta
Ctenophorescomb jellies
• Solitary
• All marine
• Sexual reproduction
Ctenes of comb row
Feeding
• Feed with specialized cells called colloblasts or lasso cells.
• A few species have cnidocytes.
Colloblasts on ctenophore tentacles
colloblasts
Kleptocnidae
Ph. Ctenophora
Coeloplana sp. Cestus sp.
Cl. Nuda
Pleurobrachia sp.
Deiopea kaloktenota
ctene row
Cl. Tentaculata
Bioluminescence
• Produce light using photocytes
• Located in the walls of the digestive system
• Appears that light is coming from comb rows
• NOT all produce luminescence
Big Picture
• The radiate phyla are the first (i.e. basal) Metazoans
• Most have a dimorphic life cycle
• Specialized structures the Cnidocytes
• Some such as corals secrete a calcium carbonate base
• Ctenophores produce bioluminescence
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