Pacificincola perforata


Scientific Name: Pacificincola perforata

Phylum: Bryozoa

Class: Gymnolaemata

Order: Cheilostomatida

Family: Pacificincolidae

Genus: Pacificincola *spelled Pacificinocla in invertebrate database but most likely a typo there *first named as Mucronella perforata(Okada and Mawatari 1937, cited in Liu and Liu 1999)


perforata [Describe here as A. iricolor]

Native Distribution

Origin Realm:

Arctic, Temperate Northern Pacific, Central Indo-Pacific

Native Region:

Origin Location:

Temperate Northern Pacific [Japan] Sea of Japan; Onagaway Bay (Grischenko and Zvyagintsev 2012; De Blauwe 2006; Liu and Liu 1999) STATUS STATED [Japan] Onagawa Bay (as Mucronella perforata (Synonymized taxon). (Okada & Mawatari 1937) STATUS NOT STATED [Japan] Around the Miura Peninsula, eastern Sagami Bay (west side of Miura Peniusula) and Kaneda Bay facing Tokyo Bay (east side of Miura Peniusula). (Hirose 2010) STATUS NOT STATED [China] Shangdong Province; Zhejiang Province; Pingtan Island; Fujian Province (De Blauwe 2006; Liu and Liu 1999) STATUS NOT STATED [Russia] Amurskiy Bay (Peter the Great Gulf). (Grischenko & Zvyagintsev 2012) STATUS NOT STATED Central Indo-Pacific [China] Hong Kong; Daya Bay; Guangdong Province (De Blauwe 2006; Liu and Liu 1999) STATUS NOT STATED [China] Mirs Bay, Hong Kong (as Hoppoporina perforata (Synonymized taxon)). (Huang & Li 1990) STATUS NOT STATED Arctic Bering Sea. (Sirenko (ed.) 2013) STATUS NOT STATED

Geographic Range:

[Western Pacific] Japan; China and Hong Kong (De Blauwe 2006; Liu and Liu 1999; Grischenko and Zvyagintsev 2012) [Eastern Atlantic] Atlantic Coast of Europe (De Blauwe 2006)

General Diversity:


Non-native Distribution

Invasion History:

Yes (Blauwe 2006)

Non-native Region:

Northeast Atlantic

Invasion Propens:

Temperate Northern Atlantic [Southwestern France] Bay of Arcachon (De Blauwe 2006) *Introduced [The Netherlands] Goesse Sas; Yerseke (De Blauwe 2006; De Blauwe and Faase 2004) *Introduced Goesse Sas, Oosterschelde (eastern Sheldt), the Netherland. (De Blauwe 2006, Faasse et al. 2013) *Introduced Yerseke, Oosterschelde, the Netherland. (De Blauwe 2006) *Introduced

Status Date Non-native:

[Netherlands] In 2006, species was commonly found at the lower shore at Yerseke (The Netherlands), where it was not found during visits in 2004 and 2005 (De Blauwe 2006) Bay of Arcahon (southwestern France): August 2001. (De Blauwe 2006) Goesse Sas, Oosterschelde (eastern Scheldt), the Netherland: August 2004. (De Blauwe 2006, Faasse et al. 2013) Yerseke, Oosterschelde, the Netherland: Jun 2006. (De Blauwe 2006) CONFLICT: Recorded in the Netherlands since 2004 (De Blauwe and Faase 2004, cited in Porter et al 2015)

Vectors and Spread

Initial Vector:

Aquaculture and Fisheries, Hull fouling (recreational)

Second Vector:

Aquaculture and Fisheries

Vector Details:

Import of P. perforata with oysters is the most likely vector of primary or secondary introduction as there is no intercontinental shipping to Europe from southern Chinese seas or Japan (De Blauwe 2006) The most likely route of introduction is via importation of Pacific oysters (Crassostrea gigas) (De Blauwe 2006) and from the western Pacific (Japan, China) (Faasse et al. 2013) RELATED: Main vector of transport (into Norwegian waters) is highly likely to be leisure craft, as evidenced by the frequent observation of non-native and invasive species in recreational marinas. Some of the doorknocker species may enter Norwegian waters via the aquaculture route (Porter et al 2015)

Spread Rate:

After the first record in the Netherland in 2004, currently P. p. became common in the eastern part of the Eastern Scheldt. Elsewhere in this marine embayment and in Lake Veer, P. p. has been found as well. (Faasse et al. 2023) RELATED: Could spread northwards into Norwegian waters (from Netherlands) (Porter et al 2015)

Date First Observed in Japan:

First discovered in Japan in 1937 (Okada & Mawatari 1937, cited in De Blauwe 2006; Liu and Liu 1999)

Date First Observed on West coast North America:



Impact in Japan:


Global Impact:

It is thus possible that the introduction of this species results in reduced numbers of other bryozoan species in the area. In the worst case this could result in loss of (bryozoan) species diversity. It is however unlikely that this will impact the overall functioning of the ecosystem. (Foekema et al. 2014)


Native Temperature Regime:

Cold water, Cool temperate, Warm temperate, Subtropical

Native Temperature Range:

Hong Kong: max 28.5ºC in summer and min 18.1ºC in winter. (Clark et al. 2003) Cold water, Cool temperate, Warm temperate, Subtropical (M. Otani, pers. comm.)

Non-native Temperature Regime:

Cool temperate, Mild temperate, Warm temperate

Non-native Temperature Range:

[France] Bay of Arcchon: surface water temperature fluctuates annually between 1 and 30ºC. (Deborde et al. 2008) Cool temperate, Mild temperate, Warm temperate (M. Otani, pers. comm.)

Native Salinity Regime:

Mesohaline, Polyhaline, Euhaline

Native Salinity Range:

Hong Kong: max 34.0psu in dry period and min 10.0psu in wet period. (Clark et al. 2003)

Non-native Salinity Regime:

Polyhaline, Euhaline

Temperature Regime Survival:


Temperature Range Survival:


Temperature Regime Reproduction:


Temperature Range Reproduction:


Salinity Regime Survival:


Salinity Range Survival:


Salintiy Regime Reproduction:

Polyhaline, Euhaline

Salinity Range Reproduction:


Depth Regime:

Shallow subtidal; Deep subtidal

Depth Range:

Collected at 6m depth (Grischenko and Zvyagintsev 2012) Collected from 0 to 34m depth (Liu and Liu 1999) [Japan] North of Yatarojima Island at Onagawa Bay: 34m. (Okada & Mawatari 1937) [Japan] Kaneda Bay in Sagami Bay: 14m. (Hirose 2010) [Japan] Amadaiba in Sagami Bay: 81m. (Hirose 2010) [Japan] East Sagami Bay: 13-90m. (Hirose 2010) [China ]Mirs Bay, Hong Kong: 51m. (Huang & Li 1990) [China Along the Chinese coast: 0-15m. (Liu & Liu 1999) [Russia] Amurskiy Bay (Peter the Great Gulf): 6m. (Grischenko & Zvyagintsev 2012)

Non-native Salinity Range:

Native Abundance:

Common, Few


Fertilization Mode:

See details

Reproduction Mode:


Spawning Type:


Development Mode:

See details

Asexual Reproduction:

Budding/fragmentation (Splitting into unequal parts. Buds may form on the body of the “parent”)

Reproduction Details:

RELATED: [Order: Cheilostomata] Free spawning species produce the characteristic triangular cyphonautes larva. These larvae are long-lived and planktotrophic. The larval body is enclosed in a membranous shell; the size can be up to little over 1 mm. Cyphonautes larvae are not keyed out - if possible at all. (van Couwelaar 2003) [Gymnolaemates] Internal fertilization, whether intracoelomic or intraovarian, is obligatory (Temkin 1994 and 1996, cited in Ostrovsky 2013) [Gymnolaemates] Differ from most organisms in that sperm-egg fusion does not stimulate egg activation. Egg activation may not occur until "spawned" outside of maternal zooid (Temkin 1991) [Bryozoans] While sperm is spawned through pores in lophophore tentacles, eggs are usually harbored inside the body wall, and are internally fertilized by sperm, coming in on lophophore feeding currents (Brusca and Brusca 2003, cited in Rouse 2011; Kozloff 1990, cited in Rouse 2011) [Bryozoans] Colonial hermaphrodites, with testes (spermatogenic tissue) and ovaries developing either within the same zooid (zooidal hermaphroditism) or in different zooids within the same colony (zooidal gonochorism) (Ostrovsky 2013) Members of the phylum Bryozoa are hermaphroditic. Both fertilization and egg brooding may either be internal or external (Ruppert et al. 2004) [Bryozoa] All bryozoan colonies are hermaphroditic. Autozooids may be dioecious; or monoecious, and protandrous or protogynous. (Hayward & Ryland 1999) [Bryozoa] Reproduces asexually by budding. (Mawatari 1976)

Adult Mobility:


Adult Mobility Details:

Encrusting (Liu and Liu 1999) RELATED: [Bryozoa] The abundance and taxonomic diversity of benthic bryozoan faunas are directly related to substratum. (Hayward & Ryland 1999) [Bryozoa] Bryozoan colonies are sessile (Hayami 1975) [Bryozoa] Bryozoans are a phylum of sessile, colonial suspension feeders found throughout the world in both marine and freshwater environments. (Tilbrook 2012)

Maturity Size:

Zooids: 0.62x0.28mm (De Blauwe 2006)

Maturity Age:


Reproduction Lifespan:

Settlement seasons are March to December in China. (Liu & Liu 1999)


Attachment seasons are March to December (Liu and Liu 1999)

Broods per Year:

Two; Peak attachments in May and November (Liu and Liu 1999)

Reproduction Cues:

RELATED: [Bryozoans] Experiments often used light as a cue to collect embryos/larvae (Woollacott and Zimmer 1977) [Bryozoa] In coastal species light is an important stimulus to larval release, and many cheilostomates shed larvae during the first few hours of daylight. (Hayward & Ryland 1999) [Bryozoa] In various degrees of intensity according to the species temperature also stimulates sexual reproduction. (Winston 1977)

Reproduction Time:

Peak attachments in May and November (Liu and Liu 1999) Settlement seasons are March to December in China. (Liu & Liu 1999)



Egg Size:

RELATED: [Gymnolaemata] About 200µm (Woollacott and Zimmer 1977)

Egg Duration:


Early Life Growth Rate:

RELATED: [Gymnolaemata] Two phases of larvae metamorphosis: first stage about 20mins; second stage 1-6 days (Woollacott and Zimmer 1977)

Adult Growth Rate:


Population Growth Rate:


Population Variablity:




Rocky subtidal, Oyster reef, Mussel reef, Macroalgal beds, Flotsam, Fouling

Habitat Type:

Epibenthic, Epiphytic, Epizoic, Under rock


Rock, Cobbles, Biogenic, Artificial Substrate


Semi-exposed, Protected, Very protected

Habitat Expansion:


Habitat Details:

Encrusts a wide variety of substrates, including seaweeds, hydroids, rocks, stones, shells, buoys, fishing nets and synthetic materials (bottom plates and bottom planks, fixed fishing nets, floating cages for fish culture, shrimp culture and shell culture and shells of the cultured pearl Pinctata martenseni (De Blauwe 2006; Liu and Liu 1999) [Europe] Found on empty shells of Crassostrea gigas and Mytilus edulis (shellfish cultures) (De Blauwe 2006) Underside of boulders (CABI 2016) [Japan] Attached to sea-weed at Onagawa Bay. (Okada & Mawatari 1937) [China] On the fixed concrete piers. (Huang & Li 1990) P. p. it incrusts on a wide variety of substrata including sea-weeds, hydroids, rocks, stones, shells, and other underwater objects such as buoys, bottom plates and bottom planks, fixed fishing nets, floating cages for fishculture, shrimp culture and shell culture and shells of the cultured peal Pinctada martenseni. (Liu & Liu 1999) [France] Found on the empty shell of the oyster Crassostrea gigas (De Blauwe 2006) Semi-exposed, Protected (M. Otani, pers. comm.)

Trophic Level:

Suspension feeder

Trophic Details:

RELATED: [Bryozoans] Suspension feeder...filter phytoplankton less than 0.045mm in size from the water column. (Hill 2001) [Bryozoa] Many phytoplankton species are cleary unsuitable as food for bryozoans. (Hayward & Ryland 1999) [Cheilostomata] Main food is diatom, protozoans and etc. and unappropriate sized particles are ejected (Mawatari 1976)

Forage Mode:


Forage Details:

RELATED: [Bryozoans] Suspension feeder...filter phytoplankton less than 0.045mm in size from the water column. (Hill 2001) [Bryozoa] Many phytoplankton species are cleary unsuitable as food for bryozoans. (Hayward & Ryland 1999) [Cheilostomata] Main food is diatom, protozoans and etc. and unappropriate sized particles are ejected (Mawatari 1976)

Natural Control:

RELATED: PREDATION [Predation] [Bryozoa] Browsers and grazers, including sea urchins, fish, crabs and some prosobranchs, are known to include bryozoans in their diet. (Hayward & Ryland 1998) [Predation] [Bryozoa] Bryozoans are also the prey of very many small, selective predators, some of which may be adapted to a very narrow spectrum of prey species. Among them opisthobranch predators of bryozoans are well known. (Hayward & Ryland 1999) [Predation] [Bryozoa] Other than opisthobranchs as a predator, amphipods, isopods, mites and pycnogonids have all been recorded preying on bryozoan colonies. (Hayward & Ryland 1998) EPIBIONTS [Epibionts] [Cheilostomata] It is frequently observed in Japan that several species of hydroids flourish on Cheilostomata cause damages to them. (Mawatari 1976)

Associated Species:


References and Notes


Bock, P. (2015). Pacificincola perforata (Okada & Mawatari, 1937). In: P. Bock, & D. Gordon (Eds.). World List of Bryozoa. Retrieved from CABI. (2016). Urosalpinx cinerea (American oyster drill) [original text by Marco Faasse]. In: Invasive Species Compendium. Retrieved from De Blauwe, H. (2006). On the taxonomy and distribution of the family Pacificinocolidae Liu & Liu, 1999 (Bryozoa, Cheiostomata), with the description of a new genus. Biologie, 76, 139-145. (?) De Blauwe, H., & Faasse, M. (2004). Smittoidea prolifica Osburn, 1952 (Bryozoa, Cheilostomatida), a Pacific bryozoan introduced to The Netherlands (Northeast Atlantic). Biologie, 74, 33-39. Deborde J, Anschutz P, Auby I, Glé C, Commarieu MV, Maurer D, Lecroart P, Abril G (2008) Role of tidal pumping on nutrient cycling in a temperate lagoon (Arcachon Bay, France). Marine Chemistry 109: 98–114. Faasse M, van Moorsel G, Tempelman D (2013) Moss animals of the Dutch part of the North Sea and coastal waters of the Netherlands (Bryozoa). Nederlandse Faunistische Mededelingen 41: 1-14. Foekema EM, Cuperus J, van der Weide B (2014) Risk assessment of alien species found in and around the oyster basins of Yerseke. IMARES (Rapport / IMARES Wageningen UR C014/14) : 1-38pp. Grischenko, A. V., & Zvyagintsev, A. Y. (2012). On the State of Inventory of the Bryozoan Fauna in Peter the Great Bay of the Sea of Japan in Light of Detection of the Cheilostome Bryozoans Callopora sarae and Microporella trigonellata. Russian Journal of Biological Invasions, 3(3), 172-179.сhenko_12_2.pdf Hayami T (1975) Neogene Bryozoa from northern Japan. Science Reports of the Tohoku University, Ser. 2 (Geology) 45: 83-126. Hayward PF & Ryland JS (1999) Cheilostomatous Bryozoa part 2. Hippothooidea - Celleporoidea. Synopses of the British Fauna (New Series). Barnes RSK & Crothers JH (eds.) No. 14 (Second Edition). The Linnean Society of London and The Estuarine and Coastal Sciences Association by Field Studies Council: 416pp. Hill, K. (2001) Smithsonian Marine Station at Fort Pierce. Retrieved from Hirose M (2010) Cheilostomatus Bryozoa (Gymnolaemata) from Sagami Bay, with notes on bryozoan diversity and faunal changes over papst 130 years. Doctoral thesis in Hokkaido University : 1-177pp. Huang Z & Li C (1990) The bryozoan foulers of Hong Kong and neighbouring waters. Proceedings of the Second International Marine Biological Workshop: The Marine flora and Fauna of Hong Kong and Southern China, Hong Kong, 1986. Morton B (ed.). Hong Kong University Press: 737-781. Liu, X. X., & Liu, H. L. (1999). Systematic position of Mucronella perforata Okada et Mawatari 1937. Chin. J. Oceanol. Limnol., 17(4), 338-342. Mawatari S (1976) Bryozoa (Ectoprocta). In: Animal systematics. Uchida T (ed.) Nakayama-shoten Co. Ltd., Tokyo: 35-229. (in Japanese) OBIS. Ocean Biogeographic Information System. Access date: 15-09-2016 *Note: genus level data Okada Y & Mawatari S (1937) On the collection of Bryozoa along the coast of Onagawa Bay and its vicinity, the northern part of Honshu, Japan. Science Reports of the Tohoku Imperial University, Ser. 4 (Biology) 3: 433-445. Ostrovsky, A. N. (2013). Evolution of Sexual Reproduction in Marine Invertebrates – Example of gymnolaemate bryozoans. Dordrectht: Springer Netherlands. Doi: 10.1007/978-94-007-7146-8 Porter, J. S., Jones, M. E. S., Kuklinski, P., & Rouse, S. (2015). First records of marine invasive non-native Bryozoa in Norwegian coastal waters from Bergen to Trondheim. BioInvasions Records, 4(3), 157-169. Rouse, S. (2011). Aetea anguina. Bryozoa of the British Isles. Retrieved from Ruppert, E.E., Fox, R.S., and Barnes, R.D. (2004). Invertebrate Zoology: A functional evolutionary approach. Ann Arbor, MN: Thomson Brooks/Cole. Sirenko BI (ed.) (2013) Check-list of species of free-living invertebrate of the Russian Far Eastern Seas. Russian Academy of Science Zoological Institute Explorations of the Fauna of the Seas 75: 1-256. Temkin, M. H. (1991). Fertilization in the Gymnolaemate Bryozoa (Doctoral dissertation). Retrieved from ProQuest Dissertations and Theses database. (DP23819). Tilbrook KJ (2012) Cheilostomata: first records of two invasive species in Australia and the northerly range extension for a third. Check List 8: 181-183. Van Couwelaar, M. (2003). Zooplankton and Micronekton of the North Sea. Retrieved from Winston JE (1977). Distribution and ecology of estuarine ectoprocts: A critical review. Chesapeake Science, 18: 34‐57. doi:10.2307/1350363. Woollacott, R. M., & Zimmer, R. L. (Eds.). (1977). Biology of Bryozoans. New York, NY: Academic Press


Limited information; expert opinion based on observational information or circumstantial evidence


*spelled Pacificinocla in invertebrate database but should be misspelled