Invasion History

First Non-native North American Tidal Record: 1951
First Non-native West Coast Tidal Record: 1951
First Non-native East/Gulf Coast Tidal Record: 2019

General Invasion History:

Pseudopolydora paucibranchiata was described from Onomichi, Japan, on the Seto Inland Sea (Okuda 1937, cited by Radashevsky 1993). It occurs in mudflats and shallow subtidal waters from Hong Kong (Wu and Lu 2007) to southern Sakhalin Island and the southern Kuril Islands, Russia (Radashevsky 1993). Populations in the Northeast Pacific (Baja California to Puget Sound), Southwest Pacific (Australia, New Zealand), and Northeast Atlantic (Norway, Portugal, Atlantic Spain, and Greece-Turkey) are generally believed to be introduced (Read 1975; Blake and Kudenov 1978; Carlton 1979; Ramberg and Schram 1982; Cohen and Carlton 1995; Simboura et al. 2008; Cacabelos et al. 2008; Rodrigues et al. 2011; Cinar et al. 2012). Likely vectors include ballast water, possibly hull fouling, and transplants of Pacific Oysters Crassostrea gigas from Japan. Most of these oysters were the Miyagi strain, from northeastern Honshu, but the morphology of P. paucibranchiata from this region has have not been studied (James Carlton, personal communication 2014). Molecular studies of P. paucibranchiata throughout its range will be useful for understanding its taxonomy, biogeography, and invasion history.

North American Invasion History:

Invasion History on the West Coast:

Pseudopolydora paucibranchiata was first reported from North American waters in Los Angeles-Long Beach Harbor, California (CA) in 1951 and was identified as 'Polydora (?) n. sp., by Olga Hartman, for the Los Angeles Regional Water Pollution Control Board (Blake and Woodwick 1975; Carlton 1979). It was also collected in 1951 in Newport Bay, and then in San Diego Bay in 1952 (Allen Hancock Foundation, cited by Carlton 1979). In the 1970s, P. paucibranchiata was found in Tomales Bay and Elkhorn Slough (1st record 1972), San Francisco Bay (1st record 1973), and Morro Bay and Santa Barbara Harbor (by 1975) (Blake and Woodwick 1975; Light 1977; Carlton 1979; California Academy of Sciences 2015). In San Francisco Bay, it is found in the Central, South, and San Pablo Bays, and ranges inland to the western end of Carquinez Strait (Cohen and Carlton 1995). It was found in Netarts Bay, Oregon (OR) (Stout 1976, cited by Carlton 1979), and later was collected in Humboldt Bay, CA (1st record 2000, Boyd et al. 2002); Coos Bay, OR (1st record 2010, Chapman et al. 2011); and Willapa Bay, Washington (1st record 1996, Cohen et al. 2002; Ferraro and Cole 2007). It has been reported as occurring in Puget Sound (Blake and Ruff 2007; Washington Department of Ecology 2014), but we have no information on specific locations.

In southern California, it has colonized most of the smaller bays and harbors from Santa Barbara to San Diego (Talley et al. 2000; Cohen et al. 2002; Fairey et al. 2002; Ranasinghe et al. 2005). In many of the intertidal mudflats and shallow, muddy bottoms where it was collected, it was an abundant or dominant polychaete (Blake and Woodwick 1975; Levin 1984; Ranasinghe et al. 2005). This polychaete has long-lived planktonic larvae, so ballast water is a likely vector for early occurrences in San Diego Bay and Los Angeles Harbor, where oyster plantings were limited. From Morro Bay northward, transplants of Pacific Oysters are a more possible vector. This polychaete is mostly known from tidal mudflats, but Barnard reported it from harbor pilings in Los Angeles-Long Beach Harbor (Barnard 1958). It seems that hull fouling of small boats, is a likely vector in the smaller harbors of southern California.

Invasion History Elsewhere in the World:

Globally, the distribution of this species complex may be underestimated due to misidentification. In Europe, Pseudopolydora paucibranchiata was first collected in the inner Oslofjord, Norway in 1962 (Ramberg and Schram 1982; Olsgard 1999). Holte (1998) reported it from the Holandsfjord (66°N), a 'pristine' fjord. Radashevsky (2012) lists it as a species occurring in the waters around Great Britain, and the United Kingdom's National Biodiversity Network lists 19 records on the west and east coasts of Scotland (NBN Gateway 2015). The fjord and offshore records seem inconsistent with this worm's preference for shallow, comparatively warm waters (Radashevsky 1993; Blake and Woodwick 1975). Records from estuaries in northeast Spain (Ria de Vigo in 1999, Cacabelos et al. 2008); Portugal (Ria de Aveiro, Rodrigues et al. 2011), and the Mediterranean, are less surprising. In the Mediterranean, P. paucibranchiata has been found on the Greek (in 2005, Simboura et al. 2008) and Turkish (in 2009, Cinar et al. 2012) sides of the Aegean Sea; the Sea of Marmara (in 2009, Cinar et al. 2012); and in the Venice Lagoon (since 2002, Erica Keppel, personal communication; Maggiore and Keppel 2007).

The earliest record of Pseudopolydora paucibranchiata from the Southwest Pacific was by Read (1975) from Wellington Harbour, South Island, New Zealand in 1971. Inglis et al. (2006e) reported this worm from Whangarei Harbour, on the North Island. In Australia, P. paucibranchiata was first reported from Botany Bay, New South Wales in 1973 (Blake and Kudenov 1978). It was subsequently found in Port Phillip and Westernport Bays, Victoria (1st record 1975, Blake and Kudenov 1978); South Australia (1st record 1979, Hutchings and Turvey 1984), and Queensland (Saenger 1988, cited by Walker 2009; Atlas of Living Australia 2015).


Adults of Pseudopolydora paucibranchiata have 45-70 segments. The prostomium has a rounded anterior edge and extends back to chaetiger 3 as a caruncle. The prostomium bears four black eyes in a trapezoidal arrangement and an occipital tentacle is present. Some individuals have one ot wo lateral eyes. The palps are transparent and extend backwards for 20-40 chaetigers, about half of the body length. Chaetiger 1 has small notopodial lobes near the midline, but a bundle of notochaetae is absent, while the neuropodial lobes, with a small bundle of capillary setae, lie adjacent to the palps. Low parapodial lobes are present on chaetigers 2-4, but the lobes are rudimentary on chaetiger 5. This segment is otherwise unmodified, having the same size as adjacent segments. However, the notochaetae and neurochaetae of this segment are modified. An outer row of 12-14 curved major spines, with enlarged and bent tips is arranged in a J-shaped line, which is characteristic of the genus. They are accompanied by an equal number of simple spines, with unusual constrictions near their tips, forming an inner row. From chaetiger 7 rearward, to aboutchaetiger 28, , the segments bears up to 22 dorsal branchiae. From chaetiger 8 rearward, the neuropodial chaetae are hooded hooks, with up to 20 per bundle. The pygidium bears a small, ventral, cup-like disk, with a dorsal gap. The maximum reported length is 18 mm, and 0.5 mm wide (Russia, Radashevsky 1993; Radashevsky et al. 2020), but West Coast specimens are usually about 4-6 mm (Blake and Ruff 2007). Younger worms may retain larval melanophores on their dorsal surface, but these are absent in larger worms. Living worms have branching yellow chromatophores on the palps, but these disappear in preserved specimens. Larval development has been described for populations in the Sea of Japan (Myohara 1980) and California (Blake and Woodwick 1975). Description based on: Read 1975, Blake and Woodwick 1975, Blake and Kudenov 1978, Light 1978, Radashevsky 1993, Wilson 1999, Radashevsky and Hsieh 2000, Sato-Okoshi 2000, and Blake and Ruff 2007; Radashevsky et al. 2020).

The genus Pseudopolydora appears to be a complex of 'pseudocryptic' speciies with relatively small morphological differences. Occurences of 'P. paucibranchiata' from Norwegian fjords, deep waters, and sites remote from known vectors, appear to refer to cryptic native species (Radashevsky et al. 2021b).


Taxonomic Tree

Kingdom:   Animalia
Phylum:   Annelida
Class:   Polychaeta
Subclass:   Palpata
Order:   Canalipalpata
Suborder:   Spionida
Family:   Spionidae
Genus:   Pseudopolydora
Species:   paucibranchiata


Polydora paucibranchiata (Okuda, 1937)
Polydora (Carazzia) derjugini (?) (Zachs, 1944)
Polydora ( Carazzia) orientalis (Annenkova, 1937)
Pseudopolydora paucibranchiata (Imajima & Hartman, 1964)

Potentially Misidentified Species

n. sp.

Pseudopolydora A
Northern Territory/Australia/Indo-Pacific (Radashevsky et al. 2020)

Pseudopolydora B
Kuwait/Arabian Gulf (Radashevsky et al.2020)

Pseudopolydora nordica
n. sp, Radashwvsky 2021b., described from nothern Norway (roms og Finnmark, Grøtsund Fjord, 69.795° N, 19.317° E, 92 m) and found from Portugal to Iceland (Radshevsky 2021b).

Pseudopolydora vexillosa
Pseudopolydora vexillosa (Radashevsky and Hsieh, 2000) from Vietnam.

Pseudopolydora antennata
Pseudopolydora antennata (Claparède, 1869) this species was described form Naples, Italy, and has been redescribed by Radashevsky (2021). It has been idienified from the Mediterreanean and Black Seas, and possibly from the Black Sea and Baltic (Radashevsky 2021b).

Pseudopolydora bassarginensis
Pseudopolydora bassarginensis (Zachs 1933) was described from the Sea of Japan. It is incompletely known, but has been reported from Willapa Bay, Washington and Coos Bay, Oregon (Cohen et al. 2002; Chapman et al. 2011).

Pseudopolydora floridensis
Pseudopolydora floridensis (Delgado-Blas, 2008) was described from Lake Worth Florida.

Pseudopolydora kempi japonica
Pseudopolydora cf. kempi is another species complex, which shows, morphological and developmental differences from P. paucibranchiata and also differences in habitat, by extending further into brackish estuaries, though overlapping with P. paucibranchiata in some areas (Southern 1921; Blake and Wodwick 1975). P. K. japonica (Imajima and Hartman 1966) is known from Pacific Russia, Japan and Korea (Radashvsky et al. 2020).

Pseudopolydora pulchra
Pseudopolydora pulchra (Carazzi 18183) was described from Naples, Italy, and is widely distibuted in the Mediterranean Sea, the North and Nowegian Seas (Radashevsky 2021b).

Pseudopolydora rosebelae
Pseudopoldora rosebelae is known only fron Brazil and the Indian River Lagoon, Florida Bogantes et al. 2021).



Pseudopolydora paucibranchiata is an estuarine spionid polychaete, which dwells in mud and mucus tubes in sediment, and in fouling communities on hard surfaces. The sexes are separate. Males and females mature at about 30-35 mm (Radashevsky et al. 2020). Eggs are laid in capsules, linked in strings attached to the interior of the tubes. Capsules in California and Japanese estuaries contained up to 35-50 eggs, with 7-10 capsules on a string. Larvae are released from the capsules at the 3-chaetiger stage, and feed in the plankton (Blake and Woodwick 1975; Myohara 1980). California larvae settle and metamorphose at about 13-17 chaetigers (Blake and Woodwick 1975), while Japanese larvae were reported to settle at 23-33 chaetigers, and a length of 1.5-2.8 mm, about 2 weeks after hatching at 23C (Myohara 1980). Blake and Woodwick (1975) do not give the development time, but indicate that the pattern of development was planktotrophic and longer than the short lecithotrophic larval period which they observed in P. kempi. The Japanese larvae matured 24-31 days after hatching, at 5-10 mm length and 45-50 chaetigers (Myohara 1980). Pseudopolydora paucibranchiata reaches a maximum size of 18 mm (Radashevsky 1993).

Pseudopolydora paucibranchiata is known from cold-temperate to subtropical estuarine-marine habitats from the tropics to cold-temperate waters. Its habitats include subtidal and intertidal soft substrates of sand or mud, where it oncstructs tubes up to 45 mm long, extending up to 10 mm above the surface (Radshevsky et al. 2020).. It is also known from salt marshes, and fouling communities in marinas and harbors (Barnard 1958; Blake and Woodwick 1975; Myohara 1980; Ferraro and Cole 2007). This polychaete does not seem to extend very far into brackish or hypersaline conditions, compared to some other spionids. We found reports over a range of about 15-37 PSU (Ferraro and Cole 2007; Simboura et al. 2010). It was found, with P. cornuta, in the polluted portions of Hong Kong (Lu and Wu 2007) and Izmir Bay, Turkey (Dagli et al. 2011; Cinar et al. 2012), and in harbors contaminated with copper (Neira et al. 2013). However, in the Oslofjord, Norway, abundance of P. paucibranchiata was negatively correlated with copper content (Olsgard 1999). Adults of P. paucibranchiata are capable of shifting between deposit-feeding detritus and surface-microalgae to suspension-feeding (phytoplankton and suspended particles). Their ciliated palps can either stretch over the sediment surface to pick up sediment particles, or wave in the current to pick up phytoplankton (Shimeta 1996). Pseudopolydora paucibranchiata can reach high abundances, and is probably important prey for fishes and benthic invertebrates.


Phytoplankton, benthic microalgae, detritus


Fish, crabs, shrimps

Trophic Status:

Deposit Suspension Feeder



General HabitatUnstructured BottomNone
General HabitatSalt-brackish marshNone
General HabitatMarinas & DocksNone
Salinity RangePolyhaline18-30 PSU
Salinity RangeEuhaline30-40 PSU
Tidal RangeSubtidalNone
Tidal RangeLow IntertidalNone
Vertical HabitatEndobenthicNone
Vertical HabitatEpibenthicNone

Tolerances and Life History Parameters

Minimum Salinity (‰)15Field, minimum salinity for Willapa Bay sediment (Ferraro and Cole 1996)
Maximum Salinity (‰)37Typical Aegean Sea Salinity
Minimum Reproductive Temperature11Start of spawning, Peter the Great Bay (Radashevsky et al. 2020).
Minimum Duration10Laboratory, Japan, 23 C (Myohara 1980)
Maximum Duration24Laboratory, Japan, 23 C (Myohara 1980)
Minimum Length (mm)5Minimum size at maturity (Blake and Woodiwick 1975; Myohara 1980)
Maximum Length (mm)18Russia (Radashevsky 1993; Radashevsky et al. 2020)
Broad Temperature RangeNoneCold temperate-Subtropical
Broad Salinity RangeNonePolyhaline-Euhaline

General Impacts

Ecological Impacts

Pseudopolydora paucibranchiata can be abundant in soft sediments and fouling communities, and has been found in some polluted habitats in San Diego Bay (California), Izmire Bay (Turkey) and Hong Kong (Lu and Wu 2007; Dagli et al. 2011; Cinar et al. 2012; Neira et al. 2013). It may have some ability to displace native species in stressful environments, but it is not regarded as a strong 'pollution indicator' to the same extent as Polydora cornuta.

Regional Distribution Map

Bioregion Region Name Year Invasion Status Population Status
NWP-3a None 0 Native Estab
NWP-4a None 1993 Native Estab
NWP-3b None 0 Native Estab
NWP-5 None 0 Native Estab
IP-1 None 0 Crypto Estab
NEP-V Northern California to Mid Channel Islands 1972 Def Estab
NEP-VI Pt. Conception to Southern Baja California 1951 Def Estab
NEP-IV Puget Sound to Northern California 1976 Def Estab
AUS-VIII None 1975 Def Estab
AUS-X None 1973 Def Estab
NZ-IV None 1971 Def Estab
NEA-V None 1999 Def Estab
MED-VIII None 2006 Def Estab
P170 Coos Bay 2010 Def Estab
P110 Tomales Bay 1972 Def Estab
P080 Monterey Bay 1972 Def Estab
P230 Netarts Bay 1976 Def Estab
P270 Willapa Bay 1996 Def Estab
P130 Humboldt Bay 2000 Def Estab
P062 _CDA_P062 (Calleguas) 2000 Def Estab
P070 Morro Bay 1975 Def Estab
P060 Santa Monica Bay 2000 Def Estab
P023 _CDA_P023 (San Louis Rey-Escondido) 2000 Def Estab
P030 Mission Bay 1996 Def Estab
P050 San Pedro Bay 1951 Def Estab
P065 _CDA_P065 (Santa Barbara Channel) 1975 Def Estab
P090 San Francisco Bay 1973 Def Estab
MED-VI None 2005 Def Estab
P040 Newport Bay 1961 Def Estab
P027 _CDA_P027 (Aliso-San Onofre) 1998 Def Estab
P020 San Diego Bay 1952 Def Estab
NWP-2 None 0 Native Estab
AUS-XII None 1989 Def Estab
P290 Puget Sound 2007 Def Estab
NEP-III Alaskan panhandle to N. of Puget Sound 2007 Def Estab
P112 _CDA_P112 (Bodega Bay) 1994 Def Estab
NEA-II None 2015 Def Estab
AUS-VII None 1997 Def Estab
MED-V None 2017 Def Estab
SA-II None 1999 Crypto Unk
NWP-4b None 0 Native Estab
MED-III None 2014 Def Estab
MED-IV None 2014 Prb Estab
CAR-I Northern Yucatan, Gulf of Mexico, Florida Straits, to Middle Eastern Florida 2019 Def Estab
S190 Indian River 2019 Def Estab

Occurrence Map

OCC_ID Author Year Date Locality Status Latitude Longitude


Atlas of Living Australia 2013-2016 Atlas of Living Australia. <missing URL>

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Barnard, J. Laurens; Reish, Donald J. (1959) Ecology of Amphipoda and Polychaeta of Newport Bay, California, Allen Hancock Foundation Occasional Publications 21: 1-106

Bastida-Zavala, Rolando; de León-González, Jesús Ángel; Carballo Cenizo, José Luis; Moreno-Dávila, Betzabé (2014) [Aquatic Invasive Species in Mexico], Comisión Nacional para el Conocimiento y Uso de la Biodiversidad, <missing place>. Pp. 317-336

Blake, James A.; Woodwick, Keith H. (1975) Reproduction and larval development of Pseudopolydora paucibranchiata (Okuda) and Pseudopolydora kempi (Southern) (Polychaeta: Spionidae), Biological Bulletin 149: 109-127

Blake, James A.; Kudenov, Jerry D. (1978) Spionidae (Polychaeta) from southeastern Australia and adjacent areas with a revision of the genera, Memoirs of the National Museum in Victoria 39: 171-280

Blake, James A.; Ruff, R. Eugene (2007) The Light and Smith Manual: Intertidal invertebrates from Central California to Oregon (4th edition), University of California, Berkeley CA. Pp. 309-410

Bogantes, Viktoria E.; Boyle, Michael J.; Halanych, Kenneth M. (2021) New reports on Pseudopolydora (Annelida: Spionidae) from the East Coast of Florida, including the non-native species P. paucibranchiata, BioInvasions Records 10: 577-588

Boyd, Milton J.; Mulligan, Tim J; Shaughnessy, Frank J. (2002) <missing title>, California Department of Fish and Game, Sacramento. Pp. 1-118

Britayev, T. A.; Rzavsky, A. V. (1985) [On the polydorid fauna (Polychaeta, Spionidae) of the Sea of Japan], Byulleten Moskovskogo Obshchestva Ispytatelei Prirody Otdel Biologicheskii 90: 45-49

Cacabelos, E.; Gestoso, l.; Troncoso, J. (2008) Macrobenthic fauna in the Ensenada de San Simon (Galicia, north-western Spain), Journal of the Marine Biological Association of the United Kingdom 88(2): 237-245

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Chapman, John W.; Therriault, Thomas; Harris, Leslie; Breitenstein, Ralph (2011) The 2010 PICES Rapid Assessment Survey of shallow water nonindigenous, native and cryptogenic marine species of central Oregon, Oregon State University, Hatfield Marine Center, Newport OR. Pp. 48

Cinar, Melih Ertan and 7 authors (2012) Spatio-temporal distributions of zoobenthos in soft substratum of Izmir Bay (Aegean Sea, beastern Mediterranean), with special emphasis on alien species and ecological quality status, Journal of the Marine Biological Association of the United Kingdom 92(7): 1457-1477

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Crooks, Jeffrey A.; Khim, Hugh S. (1999) Architectural vs. biological effects of a habitat-altering, exotic mussel, Musculista senhousia, Journal of Experimental Marine Biology and Ecology 240: 53-75

Dagli, E.; Çinar, M. E.; Ergen, Z. (2011) Spionidae (Annelida: Polychaeta) from the Aegean Sea (eastern Mediterranean), Italian Journal of Zoology 78(S1): 49-64

Fairey, Russell; Dunn, Roslyn; Sigala, Marco; Oliver, John (2002) Introduced aquatic species in California's coastal waters: Final Report, California Department of Fish and Game, Sacramento. Pp. <missing location>

Ferraro, Steven P.; Cole, Faith A. (2007) Benthic macrofauna-habitat associations in Willapa Bay, Washington, USA, Estuarine, Coastal and Shelf Science 71: 491-507

Henricksen, Summer; Bollens, Stephen M. (2021) Abundance and growth of the invasive Asian clam, Corbicula fluminea, in the lower Columbia River, USA, Aquatic Invasions 17: In press

Holte, Børge (1998) The macrofauna and main functional interactions in the sill basin sediments of the pristine Holandsfjord, Northern Norway, with autecological reviews for some key-species, Sarsia 83: 55-68

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Levin, Lisa A.; Talley, Theresa Sinicrope; Hewitt, Judi (1998) Macrobenthos of Spartina foliosa (Pacific cordgrass) salt marshes in southern California: Community structure and comparison to a Pacific mudflat and a Spartina alterniflora (Atlantic smooth cordgrass) marsh., Estuaries 21: 1

Levin, Lisa; Neira, Carlos; Grosholz, Edwin D. (2006) Invasive cordgrass modifies wetland trophic function., Ecology 87(2): 419-432

Light, William J. (1977) Spionidae (Annelida: Polychaeta) from San Francisco Bay, California: a revised list with nomenclatural changes, new records and comments on related species from the Northeastern Pacific Ocean., Proceedings of the Biological Society of Washington 90(1): 66-88

Light, William J. (1978) <missing title>, Boswood Press, Pacific Grove CA. Pp. <missing location>

Lu, L.; Wu, R.S.S. (2007) A field experimental study on recolonization and succession of subtidal macrobenthic community in sediment contaminated with industrial wastes, Marine Pollution Bulletin 52: 195-205

Myohara, Maroko (1980) Reproduction and development of Pseudopolydora paucibranchiata (Polychaeta: Spionidae) under laboratory conditions, with special regard to the polar lobe formation, Journal of the Faculty of Science, Hokkaido University, Series VI 22(2): 145-155

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Neira, Carlos; Levin, Lisa A.; Mendoza, Guillermo; Zirino, Alberto (2014) Alteration of benthic communities associated with copper contamination linked to boat moorings, Marine Ecology 35: 46-66

Olsgard, Frode (1999) Effects of copper contamination on recolonisation of subtidal marine soft sediments- An experimental field study, Marine Pollution Bulletin 38(6): 448-462

Omelyanenko, V. A.; Kulikova, V. A. (2011) Pelagic larvae of benthic invertebrates of the Vostok Bay, Peter the Great Bay, Sea of Japan: Composition, phenology, and population dynamics, Russian Journal of Marine Biology 37(1): 7-22

Radashevsky, Vasily I. (1993) Revision of the genus Polydora and related genera from the North West Pacific (Polychaeta: Spionidae), Publications of the Seto Marine Biological Laboratory 36(1/2): 1-60

Radashevsky, Vasily I. (2012b) Spionidae (Annelida) from shallow waters around the British Islands: an identification guide for the NMBAQC Scheme with an overview of spionid morphology and biology, Zootaxa 3152: 1-35

Radashevsky, Vasily I. (2021a) Pseudopolydora (Annelida: Spionidae) from European and adjacent waters with a key to identification and description of a new species, Marine Biodiversity 51(31): Published online

Radashevsky, Vasily I. and 8 authors (2020) Disentangling invasions in the sea: molecular analysis of a global polychaete species complex (Annelida: Spionidae:Pseudopolydora paucibranchiata), Biological Invasions 22: 3621-3644

Radashevsky, Vasily I.; Hsieh, Hwey-Lian (2000) Pseudopolydora (Polychaeta: Spionidae) species from Taiwan., Zoological Studies 39(3): 218-235

Ramberg, Jens Petter; Schram, Thomas (1982) A systematic review of the Oslofjord species of Polydora Bosc and Pseudopolydora Czerniavsky, with some new biological and ecological data (Polychaeta: Spionidae), Sarsia 68: 233-247

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Ranasinghe, J. Ananda and 6 authors. (2005) The prevalence of non-indigenous species in southern California embayments and their effects on benthic macroinvertebrate communities, Biological Invasions 7: 679-686

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Rodrigues, Ana Maria; Quintino, Victor; Sampaio, Leandro; Freitas, Rosa; Neves, Ramiro (2011) Benthic biodiversity patterns in Ria de Aveiro, Western Portugal: Environmental-biological relationships, Estuarine, Coastal and Shelf Science 95: 338-348

Ruiz, Gregory; Geller, Jonathan (2021) Spatial and temporal analysis of marine invasions: supplemental studies to evaluate detection through quantitative and molecular methodologies, Marine Invasive Species Program, California Department of Fish and Wildlife, Sacramento CA. Pp. 153 ppl.

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Soors, Jan; Faasse, Marco; Stevens, Maarten; Verbessem, Ingrid; De Regge, Nico;Van den Bergh, Ericia (2010) New crustacean invaders in the Schelde estuary (Belgium), Belgian Journal of Zoology 140: 3-10

Talley, Theresa Sinicrope; Dayton, Paul K.; Ibarra-Obando, Silvia E. (2000) Tidal flat macrofaunal communities and their associated environments in estuaries of southern California and northern Baja California, Mexico, Estuaries 23(1): 97-114

Tamaki, Akio (1985) Inhibition of larval recruitment of Armandia sp. (Polychaeta:Opheliidae) by established adults of Pseudoplydora paucibranchiata (Okuda) (Polychaeta: Spionidae) on an intertidal sand flat, Journal of Experimental Marine Biology and Ecology 87: 67-82

U.S. National Museum of Natural History 2002-2021 Invertebrate Zoology Collections Database.

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