Assemblages of intertidal bryozoans are proving to be more species‐rich than generally previously appreciated. This study found 31 species of cheilostome bryozoans at three rocky‐intertidal sites at Ketchikan, Alaska, USA. Species richness varied considerably among the three collecting sites: 28 at East Tongass Narrows, 18 at Higgins Point, 10 at Settlers Cove. Each site had species not occurring at the other sites (12, two, and one species, respectively). The number of species per site was within the range of values previously observed in a more extensive study at Kodiak, Alaska, suggesting both similar intertidal species richness at the two localities, and that sampling of other intertidal sites at Ketchikan would detect additional species. Descriptions and scanning electron microscopy (SEM) illustrations are provided for the species found at Ketchikan, and SEM illustrations are included for the holotypes of Porella acutirostris Smitt, 1867 and Schizoporella japonica Ortmann, 1890; a paralectotype of Porella columbiana O'Donoghue and O'Donoghue, 1923; and a specimen of Cauloramphus pseudospinifer Androsova, 1958. Fenestrulina delicia Winston, Hayward, and Craig, 2000 is illustrated and described from subtidal specimens from Sitka, Alaska. Eight species (26% of total species) are described as new (Cauloramphus multiavicularia n. sp., Cauloramphus tortilis n. sp., Puellina caesia n. sp., Celleporella nodasakae n. sp., Porella donoghueorum n. sp., Microporella ketchikanensis n. sp., Fenestruloides tongassorum n. sp., and Rhynchozoon glabrum n. sp.). Membranipora serrilamella Osburn, 1950 and nominal Membranipora membranacea (L., 1767) from the north‐east Pacific Ocean are considered to be junior synonyms of Membranipora villosa Hincks, 1880. Schizoporella unicornis var. japonica Ortmann, 1890 is elevated to species status as Schizoporella japonica Ortmann, 1890; many of the previous records of Schizoporella unicornis (Johnston, 1844) from the northern Pacific Ocean are likely attributable to S. japonica. Examination of type specimens of Porella columbiana O'Donoghue and O'Donoghue, 1923 show that Osburn's (1952) concept of this species was in error; the taxon treated by Osburn and subsequent authors as P. columbiana is described herein as Porella donoghueorum n. sp. Although Porella acutirostris Smitt, 1867 has been previously considered a circumpolar, arctic‐boreal species, it is questionable whether this species occurs in the boreal North Pacific. Nominal P. acutirostris probably comprises a complex of morphologically similar, closely related species in the northern hemisphere that includes Porella major Hincks, 1884 and Porella columbiana O'Donoghue and O'Donoghue, 1923. Of the 31 cheilostomes detected intertidally at Ketchikan, only Schizoporella japonica and Fenestrulina delicia are considered as actually or potentially introduced species. The introduction of S. japonica (previously reported as S. unicornis) to the north‐eastern Pacific on Pacific oysters from Japan has been well documented in the literature. Fenestrulina delicia, originally described from Maine in 2000, is reported for the first time from the north‐eastern Pacific Ocean.
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