Cribrimorph and Other Cauloramphus Species (Bryozoa: Cheilostomata) from the Northwestern Pacific

We provide original descriptions for nine new species in the cheilostome bryozoan genus Cauloramphus (C. gracilis, C. Ordinarius, C. amphidisjunctus, C. cheliferoides, C. oshurkovi, C. infensus, C. parvus, C. peltatus, and C. ascofer) and a redescription of C. disjunctus Canu and Bassler, 1929. We delineate a group of eight species, here termed the ‘C. disjunctus clade,’ that have the opesial spine joints calcified to a greater or lesser extent in mature zooids; most also have paired, hypertrophied avicularia. This group includes C. amphidisjunctus, C. cheliferoides, C. infensus, C. parvus, C. peltatus, and C. ascofer in the Aleutian Islands, Alaska; C. oshurkovi in the Commander Islands; and C. disjunctus in Japan. High levels of apparent endemism in two unrelated bryozoan genera (Cauloramphus and Monoporella), and geographical population differentiation in C. ascofer indicating ongoing allopatric speciation, suggest high speciation rates for deep benthic bryozoans in the western Aleutians. A phylogeneti...