Pegea confoederata (Forskal, 1775), top; P. socia (Bosc, 1802), bottom 
Phylum Chordata / Subphylum Urochordata / Class Thaliacea / Order Salpida / Family Salpidae

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.

FacebookTwitterGoogle+PinterestLinkedInGoogle BookmarksStumbleUponRedditShare

Comments are closed