Ecological correlates of Arctic Serpulidae (Annelida, Polychaeta) distributions.
Polychaetes are traditionally considered poor biogeographic indicators because of the ancient age of the phylum, world-wide geographic distribution, and taxonomic problems. Therefore, polychaetes tend to show ecological rather than geographic fidelity in their distribution. We analyzed distributions of arctic Serpulidae from ecological and historical perspective. Temperature and depth are shown to be major environmental factors controlling distributions. Substrate associations differed significantly among studied species and appeared to be determined by various sedimentation tolerance of individual species. Bathymetrically, the Arctic serpulid fauna is mostly eurybathic, mostly consisting of lower sublittoral-upper bathyal and lower-sublittoral-bathyal species. The fauna of arctic serpulids consists of North-Atlantic boreal and Mediterranean forms with complete absence of Pacific elements. Both distributional ranges and ecological characteristics suggest that the fauna of arctic serpulids consists of post-glacial Atlantic and Mediterranean migrants penetrating into the Arctic with warm Atlantic currents, with the addition of deep-water relicts of the pre-glacial fauna. The geographic distribution of arctic serpulids appears to be a complex interplay of historical and ecological factors.