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Galathowenia oculata is a member of the peculiar tubeworms group Oweniidae. This is a small group of 55 benthic species worldwidespread from the continental slope to abyssal depths, mostly at soft sediments like mud or sand which particles worms use for feeding and tube construction. The phylogenetic position of the group has been changed many times. Previously they were regarded as a member of primitive basal “Archiannelida”, then they were referred to sedentary filter-feeding Sabellidae together with derived “Siboglinidae”, then were grouped only with “Siboglinidae”, then referred to spionid polychaetes Apistobranchidae, then placed as basal polychaete and recently again they were considered again as a basal group of Annelida. In spite of their evident polychaete-like appearance oweniids do not have typical spiralian embryogenesis; there is gastrulation via invagination like in Deuterostome and Lophophorates, deuterostome mouth-formation, unique mitraria larvae, catastrophic metamorphosis like in Nemertines, Phoronida, Echinodermata and “polychaete” Polygordiidae, monociliated epidermis like in Phoronida, Brachiopoda, Echinodermata, Hemichordata and also Gnathostomilida, Gastrotricha, “polychaete” Magelona, deuterostome-like nephridium, intraepidermal nervous system and muscle regulation through basal lamina like in Echinodermata, Hemichordata and Phoronida, absence of internal dissepiments etc. Thus, combination of the results of phylogenetic analysis, peculiar morphology and unique development pattern can be the reason to speculate that Oweniidae are really basal representatives among Annelida. Recently, the primitive organization of the nervous system of G. oculata was shown by the author and colleagues: absence of brain as well as any other ganglia, massive nervous plexus in body wall and numerous longitudinal nerve cords with the main ventral one. It is uncertain if the condition of nervous system is determined by catastrophic metamorphosis, either by the ecology of burrowing animal without numerous appendages and sensory structures, or by basal position within Annelida. In this regard, G. oculata is an intriguing model object for evo-devo experiments to understand mechanism of nervous system formation, including such questions like absence of ganglia, plexus development and why the nervous system retains in epidermis. This presentation is necessary for discussion and planning of a new project.