Description:
This Scyphomedusa has
a saucer-shaped bell
up to 2 m in diameter at high latitudes; more southern specimens such
as
those near Rosario are usually closer to 50 cm. The bell has
a thick
center and a thinner margin. The margin is divided into 8
pairs of
thick lobes (for a total of 16 lobes) (photo).
Has 8 clusters of up to 150 highly extensible tentacles arranged in
several
rows, arising from horseshoe shaped regions between the lobes (photo).
Has 8 rhopalia,
each of which is situated between the two lobes of a pair (photo).
Oral
arms highly
folded, forming a blocky mass only about as long as the bell is wide
(but
see this photo
for extended oral
arms). Color deep brick red to purplish, rose,
violet, or even
milky white. Yellowish-brown in small specimens, often more
red in
large individuals. The swimming medusa looks like an 8
pointed star
at the end of its power stroke. The tentacles may trail down
as far
as 9 m in large specimens, 2 m in the 50 cm individuals found in our
area.
How to Distinguish from Similar Species: Phacellophora camtschatica also has 16 large marginal lobes, but they are not in pairs and between these are 16 smaller lobes resembling fish tails on which the rhopalia are found. The tentacles are in 16 linear groups (not 8) of up to 25 tentacles per group, hanging from the subumbrella. It is usually a lighter yellow color than is Cyanea capillata. Geographical Range: Arctic and north boreal. In the Pacific it is common as far south as Washington, occasionally seen in Oregon, and probably not as far south as California. In the Atlantic it can be found as far south as Florida and Mexico. Depth Range: Pelagic Habitat: Pelagic near surface, in polar and temperate coastal waters. Biology/Natural History: Probably lives less than one year. This species can give a painful sting with blisters that lasts for several hours. It is the most likely jellyfish in our area to sting you, and may even trigger allergic shock. Feeds on small fish and crustaceans. Several symbionts may be found on the bell, including juvenile pollock and other fish, and decapod megalops larvae. The gonads of this species are 4 highly folded, ribbonlike structures that hang down under the bell and alternate with the 4 oral lobes. This is the world's largest jellyfish.
References:Dichotomous Keys:Flora and Fairbanks, 1966 Kozloff 1987, 1996 Smith and Carlton, 1975 General References:
Scientific
Articles:
Web sites:
General Notes and Observations: Locations, abundances, unusual behaviors: This is one of the most prominent and common jellyfish species seen around Rosario, especially in late summer.
Authors and Editors of Page: Dave Cowles (2007): Created original page (an older page was prepared by Christina Smith) Jonathan Cowles (2007): Updated page with CSS |