Ritterella rubra Abbott & Trason, 1968

Figure 8 D–G

RHAK 2 BHAK 0601, 0602 UF 2460. Goose Island Group, Duck Island, low rocky intertidal.

One colony with two large heads and many smaller ones but only the large heads collected; largest one 1.8 cm wide at widest part and slightly flattened with short thick stalk, 3.9 cm long but had been cut off above the base. Sandy leathery tunic reddish-orange, lightly encrusted with sand and shell debris but none in the internal tunic which is translucent, somewhat tough and gel-like. Siphons are close together, bright red. Zooids orange, about 14 mm long, with about 14 rows of stigmata; the zooids were somewhat contracted making counts difficult. Stomach globular, very obscurely and irregularly lobed. Atrial chamber full of bright pinkish-red embryos in various stages of development, the most mature with three adhesive papillae in a row and numerous very short ampullae in several rows on each side as described by Abbott & Trason (1968); it was not possible to count them. Postabdomen extends into the stalk, with the ovary at the anterior end and containing a dozen or more orange or pinkish ova; testes follow with some testes covering the posterior portion of the ovary. All the morphological characters agree with the description given by Abbott & Trason (1968) except for the presence of one or two additional rows of stigmata; Abbott & Trason give the number as varying from 10–13 in colonies from the type locality in Monterey County, central California. A colony from SE Alaska (O’Clair & O’Clair 1998) collected 5/25/1994 and identified by me also had 14 rows of stigmata. A name change was proposed by Brunetti (2007) based on his transferring the species to the genus Synoicum Phipps, 1774, but this change is rejected because the distinguishing morphological characters for R. rubra place it in the genus Ritterella Harant, 1931, not Synoicum .

This species is known from British Columbia to central California (Abbott & Trason 1968, Abbott & Newberry 1980, O’Clair & O’Clair 1998, Lamb & Hanby 2005; Abbott et al. 2007).