Tubularia indivisa Linnaeus, 1758 Fig. 18 Tubularia indivisa Linnaeus, 1758: 803.— Segerstedt, 1889: 11, 24.— Lönnberg, 1902: 173; 1903: 59.— Jäderholm, 1909: 42, pl. 2, figs. 4–5.— Gislén, 1930: 350.— Rees & Rowe, 1969: 7.— Jägerskiöld, 1971: 64.— Jonsson et al., 2004: 166.— Schuchert, 2010: 343, fig. 2A. Type locality. “ Habitat in Oceano Europaeo ” (Linnaeus 1758: 803). Museum material. Kosterhavet, 58°53.093’N, 11°05.668’E, 20–30 m, 09.ix.2010, biological dredge, R / V Nereus, two stems with hydranths, up to 9.5 cm high, one with incipient gonophores, ROMIZ B3908. Remarks. Details on taxonomy, nomenclature, distribution, and general biology of Tubularia indivisa Linnaeus, 1758 are provided in a recent monograph by Schuchert (2010). He noted that the identity of Tubularia divisa Osburn, 1893 is unclear, but that the name is perhaps a spelling mistake. In briefly describing the species, Osburn (1893) associated it with accounts in Seaside Studies (E.C. Agassiz & A. Agassiz 1865) of Tubularia couthouyi L. Agassiz, 1862 and in The Riverside Natural History (Clarke 1888) of Parypha crocea L. Agassiz, 1862 (= Ectopleura crocea), together with a plate of Tubularia indivisa. The name is taken here to be an incorrect subsequent spelling of T. indivisa and, as such, not an available name (ICZN Art. 33.3). The status of T. couthouyi remains unresolved, with Fraser (1944) maintaining it as valid, Petersen (1990) regarding it conspecific with T. indivisa, and Schuchert (2010) considering it questionably so. Tubularia indivisa is relatively common in southwestern Scandinavia, particularly at depths of about 10–100 m (Kramp 1935b; Rees & Rowe 1969; Jägerskiöld 1971; Christiansen 1972). Christiansen found fertile colonies from February to May in the Oslofjord. Reported distribution. West coast of Sweden.—From the border with Norway (Jägerskiöld 1971) to the Öresund (Segerstedt 1889). Elsewhere.—North Atlantic from northern seas of the Russian Federation to Ghana (Schuchert 2010) in the east, and from west Greenland (Schuchert 2001a) and the Gulf of St. Lawrence to Block Island Sound (Fraser 1944) in the west. This species has also been reported in the boreal North Pacific Ocean from the Bering Sea to northern Japan in the west, and from Alaska to Washington state in the east (Petersen 1990).

Published as part of Calder, Dale R., 2012, On a collection of hydroids (Cnidaria, Hydrozoa, Hydroidolina) from the west coast of Sweden, with a checklist of species from the region 3171, pp. 1-77 in Zootaxa 3171 (1) on page 19, DOI: 10.11646/zootaxa.3171.1.1, http://zenodo.org/record/5247704