
When in the aggregate phase, salps in the genus
Pegea can
be distinguished from other West Coast species by the pattern of zooid linkage : the
axes of individuals are at right angles to the axis of the chain, like cans in a six-pack
of soda. Aggregates form double-row chains in the form of a tight spiral coil.
Since the direction of swimming is at a right angle to the axis of the chain,
Pegea swims
slower than species of
Salpa, in which the chain axis and direction of swimming
are aligned. Zooids have distinctly cylindrical bodies with soft tests, length from
6 to 12 cm. Of the two species of
Pegea that can be found on the West
Coast,
P. socia is more likely to be seen north of central California. It
is distinguished from
P. confoederata by its gold-colored
pigmentation. Solitary individuals of both species have more plump bodies,
with lengths up to 14 cm. The gut forms a tight nucleus. The developing stolon
is very distinctive, forming two complete loops around the gut, with a chain of up to 200
zooids.
All photographs © David
Wrobel and may not be used or copied without permission!
[ Cyclosalpa affinis ] [ Cyclosalpa bakeri ] [ Dolioletta ] [ Helicosalpa ] [ Iasis ] [ Oikopleura ] [ Pegea ] [ Pyrosoma ] [ Salpa ] [ Thalia ] [ Thetys ] [ Weelia ]