Dismantling the (Busk, 1852) species complex (Bryozoa, Cheilostomata): two new species from European waters.

New research on bryozoans has determined that formerly widespread species are in many cases complexes of similar, but distinct, species with more restricted distributions. Notwithstanding, the limits of distribution are still unresolved for many taxa, and occasionally a wide distribution is confirmed. has been considered a widespread species, distributed throughout the Southern Hemisphere, parts of northern Pacific and Atlantic Oceans and the Mediterranean Sea. This study examines the Magellanic-type material, together with other historic samples and new specimens collected in the western Mediterranean and Adriatic, and for the first time, presents specimens from the European North Atlantic. Morphological comparisons and biometric analysis show the existence of three different species among the specimens studied. A redescription of based on the type specimen is presented, and two new species are described: sp. nov. from the Northeast Atlantic and sp. nov. from the Mediterranean Sea. These results indicate that s.l. is a large complex of species and that most specimens from different parts of the world must be revised.