A review of the worldwide distribution of Marenzelleria viridis, with new records for M. viridis, M. neglecta and Marenzelleria sp. (Annelida: Spionidae) Author Radashevsky, Vasily I. A. V. Zhirmunsky National Scientific Center of Marine Biology, Far Eastern Branch of the Russian Academy of Sciences, 17 Palchevsky Street, Vladivostok 690041, Russia. Author Pankova, Victoria V. A. V. Zhirmunsky National Scientific Center of Marine Biology, Far Eastern Branch of the Russian Academy of Sciences, 17 Palchevsky Street, Vladivostok 690041, Russia. Author Malyar, Vasily V. A. V. Zhirmunsky National Scientific Center of Marine Biology, Far Eastern Branch of the Russian Academy of Sciences, 17 Palchevsky Street, Vladivostok 690041, Russia. Author Cerca, José Natural History Museum, University of Oslo, P. O. Box 1172, Blindern, NO- 0318 Oslo, Norway. Author Struck, Torsten H. Natural History Museum, University of Oslo, P. O. Box 1172, Blindern, NO- 0318 Oslo, Norway. text Zootaxa 2021 2021-12-13 5081 3 353 372 journal article 2998 10.11646/zootaxa.5081.3.3 a8980f07-e2f6-440e-a3fb-5b26636382ee 1175-5326 5775688 0173F43D-38AB-4010-8B2A-1DFD5F118A2C Marenzelleria neglecta Sikorski & Bick, 2004 ( Figs 1 & 2 ) Marenzelleria neglecta Sikorski & Bick, 2004: 264–268 , figs 2B, 3C, 5A–I, 6. Syomin et al. 2017: 977−979 , figs 2−5. Blank & Bastrop 2009: 316-318 , fig. 1 (phylogeny). Marenzelleria viridis : Maciolek 1984 ( Part .) : 51–55, fig. 2. Bick & Burckhardt 1989: 239−241 , fig. 1, pls VII−VIII. Bastrop et al. 1995 : Baltic Sea population. Bochert & Bick 1995: 764−772 , figs 2−12 (larval morphology). Bochert 1996a: 58−68 , figs 1−31 (oogenesis); 1996b: 192−198, figs 1−27 (spermatogenesis). Röhner et al. 1996a : Baltic Sea population. Ysebaert et al. 1996: 178−179 . Sikorski & Buzhinskaya 1998: 1118−1119, fig. 4. Fide Sikorski & Bick 2004 ( Part .): 264. Not Verrill 1873 . ? Marenzelleria viridis : Cohen & Carlton 1995 : A4-1. Thompson et al . 2000: 15 ; 2013: 2290 . Cohen et al. 2005: 11 . Ranasinghe et al . 2012: 646 . Marenzelleria cf. viridis : Bick & Zettler 1997: 141−142 , figs 3, 4. Fide Sikorski & Bick 2004: 264 . Marenzelleria type II: Röhner et al. 1996b: 281−283 . Bastrop et al. 1997: 125−127 ; 1998: 98−102 . Fide Sikorski & Bick 2004: 264 . Remarks. Bastrop et al. ’s (1997, 1998) Marenzelleria Type II was found on the both sides of the North Atlantic and not formally named until Sikorski & Bick (2004) described it as a new species, M. neglecta . As noted above, Darss- Zingst-Boddenchain, Baltic Sea, Germany , was designated as the type locality of the species, although M. neglecta was recognized as alien in Europe, being introduced with ballast water from the Atlantic coast of USA ( Bastrop et al. 1997 , 1998 ). Based on genetic data (allozyme electrophoresis and/or 16S sequences), Bastrop et al. (1997 , 1998 ) documented the presence of M. neglecta (as M. Type II) in the United States (Durham, New Hampshire ; Chesapeake Bay, Maryland ; Currituck Sound, North Carolina ; Ogeechee River estuary, Georgia ) and in Canada (Tuktoyaktuk Harbor, Northwest Territories ) ( Fig. 2 ). Notably, specimens of the only sample from New Hampshire (Durham, USNM 80485) were morphologically assigned to M. viridis by Maciolek (1984 *), Sikorski & Bick (2004) , as well as one of us (VIR, May 2000 ). Bastrop et al . (1997: 128) sequenced the 16S mitochondrial fragments of three specimens from this sample and noticed that “Contradictions between the results of morphological and genetic species determination still exist … DNA sequence analysis has shown beyond doubt that these animals [USNM 80485] belong to Marenzelleria Type II [ M. neglecta ].” Based on the morphology, Sikorski & Bick (2004) identified M. neglecta from San Francisco Bay ( California , USA ). After the description of M. neglecta , Leslie H. Harris ( in litt . 2 June, 5 July 2021 ) re-identified as M. neglecta specimens initially reported as M. viridis from California , USA (see below Remarks for M. viridis ). Moreover, Leslie H. Harris ( in litt . 5 July 2021 ) identified M. neglecta collected during the 2020 National Coastal Condition Assessment from Ilwaco marina, Columbia River mouth, Washington , USA (see VIR ID 24756 in Table S4). Following these identifications, reports of M. viridis from San Francisco Bay by Thompson et al. (2000 , 2013 ) are also referred herein to M. neglecta . Complete information about records of M. neglecta from North America is given in Table S4. Distribution in North America. Atlantic coast: from New Hampshire south to Georgia , USA . Pacific coast: Washington and Northern California , USA . Arctic coast: Northwest Territories , Canada ( Fig. 2 ). * Maciolek (1984: 52) mistakenly exchanged the catalogue numbers for two specimens collected by Jones, M. L. in Gloucester ( Massachusetts ) on 16 May 1959 ( USNM 80483 ), and nine specimens collected by Long, C. D. at Fox Point ( Durham , New Hampshire ) on 24 Jul 1962 ( USNM 80485 ) .