Hydroids

Tubularian Hydroid  

Tubularian Hydroid (Tubularia crocea) - Most common hydroid. Looks like a cluster of beautiful tiny flowers with short tentacles. Can be difficult to identify from other hydroids when flowers are not present. Flowers (hydranths) can be red, pink, or white in color. Grows sub-tidally on hard substrate to 5" high and colony sizes up to12" wide.

   

Zig-Zag Wine Glass Hydroid  

Zig-Zag Wine Glass Hydroid (Obelia geniculanta) - Short Hydroid grows to about 1" high and up to 12" wide. Hydranth's (reproductive flowers) are conical and grow in a zig-zag pattern up the 1" stem. Whitish color. Found in shallow water on rocks, kelp and other algae.

   

Stick Hydroid  

Stick Hydroid (Eudendrium ramosum) - Medium height hydroid grows to 6" high, with single small, tulip-shaped flower at end of each stick. Can be difficult to identify if flowers not present. Pink in color. Grows on solid substrate.

   

Many-Armed Hydromedusa  

Many-Armed Hydromedusa (Laodicae undulata) - Flattened, transparent saucer shape to 1 3/8" in diameter with white ribbons not joining in the center. Resembles White Cross Hydromedusa whose white ribbons connect in the center. Found near the surface in coastal waters.

   

Eight-Ribbed Hydromedusa  

Eight-Ribbed Hydromedusa (Melicemtum octocostatum) - Bell shaped to ¾ inch in diameter. Eight rows of canals that are gold or white in color. Swims near the surface. Found from spring to summer.

   

Siphonaphore  

Siphonaphore (Stephanomia) - Colony of pelagic Hydrozoa. Each section performs separate functions such as reproduction, locomotion, flotation, or feeding. Floats close to shore. Lengths up to 4'.

     
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