Adult black jellyfish have tentacles measuring up to 30 feet (over 9 meters) in length

Jul 10, 2013 05:55 GMT  ·  By

Last week, people enjoying a quiet day at the beach in Southern California had their fun spoiled by several black jellyfish that showed up in the waters near the Thousand Steps Beach.

Eyewitnesses told the press that many swimmers were forced to get out of the water after being stung by these rare marine creatures.

They also said that the jellyfish were dark in color, and that they had very long tentacles, The Inquisitr reports. Apparently, one witness chanced to catch a glimpse of a jellyfish the size of a hula-hoop.

Wildlife researchers explain that black stinging jellyfish are typically found in the waters off the coast of Mexico and Baja California.

They have seldom been documented in Southern California, and appear to have only recently taken a liking to these regions.

Adult specimens sport very long tentacles, some of which can measure up to 30 feet (over 9 meters) in length. Despite being called black jellyfish, they usually have a reddish color.

These jellyfish deliver a very painful sting, but it rarely happens that the people stung by them develop complications.