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Index of flora
Index of fauna
Kingdom Animale | Phylum Cnidaria (=Coelenterata)
Cnidarians on this site
Order Rhizostomeae
Rhizostome Jellyfish

Order Hydroida
Stinging Hydroids

Order Madreporaria
Hard Corals

Order Alcyonacea
Soft Corals

Order Actiniaria
Sea Anemone Stoichactis
Banded Bead

Order Cerianthiaria
Snakelock or Peacock Anemone Cerianthus

Order Zoanthidae
Colonial Anemones

Order Semaeostomeae
Sea Nettle Chrysaora melanaster
Phylum Cnidaria
They generally show radial symmetry and are flower-like. The single body opening which serves as both mouth and anus is usually fringed by tentacles bearing cells (nematocysts) which can sting and paralyse prey.
They normally occur in two forms: polyps or hydroids (flower- like), which are stationary, and free-living medusae (left) (jellyfish-like). Some species occur in only one form throughout their life while others may show an alternation of generation (i.e., they occur as both hydroid and medusoid forms at different stages in their life).

Hydroid stage
(Order Hydroida)
Shore environment
From A Guide to Seashore Life by Dr Leo W H Tan and Peter K L Ng
Published by the Singapore Science Centre and sponsored by BP

@Raffles Museum of Biodiversity Research and Singapore Science Centre