For shear impressiveness, it's hard to surpass the Lion's mane jelly.  Just imagine encountering a gelatinous beast that can reach a bell diameter of 2 meters (that's over 6 feet folks!).  Individuals off the West Coast are usually far more modest, however, with bells no wider than 50 cm.  Cyanea resembles the egg-yolk jelly (Phacellophora), but has a bell margin divided into 8 lobes (rather than 16), with 8 rhopalia and 8 clusters of up to 150 tentacles each.   The seemingly tangled oral arms are short and compact, with the tentacles extending much longer.   The tentacles are very sticky, a useful trait for a jelly that preys on other gelatinous creatures.   Body color can range from deep red to reddish-purple, with younger individuals having a yellowish-brown hue.  As seen in the photo, the bell has an 8-pointed star shape at the end of the contraction while swimming.  The Lion's mane jelly is generally a summertime visitor to nearshore waters.  It ranges from Arctic and North Pacific Ocean areas to Alaska, British Columbia and Washington, but is rarely seen as far south as California.  The truly massive giants are more likely to be seen in the northern part of the range. 

All photographs © David Wrobel and may not be used or copied without permission!