Perophora japonica

Invasion History

First Non-native North American Tidal Record: 2003
First Non-native West Coast Tidal Record: 2003
First Non-native East/Gulf Coast Tidal Record:

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General Invasion History:

Perophora japonica is native to Japan, Korea, and Peter the Great Bay, near Vladivostok, Russia (Nishikawa 1991, Sanamyan 1998). It is introduced to Humboldt Bay and San Diego Bay, California and parts of Europe. Ship hull fouling is the probable vector for this tunicate.

North American Invasion History:

Invasion History on the West Coast:

Perophora japonica was found on oyster rafts in the North Slough of Humboldt Bay, California (CA) in August 2003. This appeared to be an established population (Lambert 2005). In 2011, P. japonica was identified from San Diego Bay, CA (Gretchen Lambert 2012, personal communication). In 2012, specimens were found on fouling plates in Bodega Harbor, CA, apparently established (Ruiz et al. unpublished data). Fouling on recreational boats and commercial ships or with aquaculture species are possible vectors for this tunicate.

Invasion History Elsewhere in the World:

Perophora japonica was found in Lezardrieux on the north coast of Brittany, France, in 1982 (Monniot and Monniot 1985, cited by Nishikawa et al. 2000). Subsequently, it appeared at other European coastal sites including Guernsey, in the Channel Islands (in 2003, MarLin 2007), Plymouth, England (in 1999, Nishikawa et al. 2000; MarLin 2000), St. Vaast, Normandy, France (Goulletquer et al. 2002), and the Oosterschelde in the Netherlands (in 2000, Gittenberger 2007). From 2008 to 2009, two colonies were found in Baiona, Spain and are the first records on the Iberian peninsula (El Nagar et al. 2010).

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Description

Perophora japonica is a colonial tunicate. Colonies consist of small (4-6 mm), translucent, yellow-green ellipsoidal zooids growing from stolons at the base of the tunic. The longitudinal vessels of the branchial sac are incomplete. The mantle musculature is delicate and connected to the anterior region around and between the siphons. The mantle surface is reticulated with pale greenish corpuscles with about 20 mantle muscles on each side; 25-40 stigmata, in rows on both sides of the mantle surface, and 7-8 branchial papillae, in rows. There are about 20 tentacles around the oral aperature. A unique feature of this species is the occurrence of terminal buds, bright yellow star-shaped plaques at the tip of the stolon which break off, float away, and grow into new colonies (Nishikawa 1991; Nishikawa et al. 2000; Lambert 2005).

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Taxonomy

Ecology

General:

Life History- A colonial (or compound) tunicate consists of many zooids, bearing most or all of the organs of a solitary tunicate, but modified to varying degrees for colonial life. Colonial tunicates of the family Perophoridae have zooids resembling solitary tunicates, rounded or oval in shape, but connected by stolons. Zooids can be crowded together, but do not coalesce. Each zooid has an oral and atrial siphon. Water is pumped into the oral siphon, through finely meshed ciliated gills on the pharynx, where phytoplankton and detritus is filtered, and passed on mucus strings to the stomach and intestines. Excess waste is expelled in the outgoing atrial water (Van Name 1945; Barnes 1983).

Colonial tunicates reproduce both asexually, by budding, and sexually, from fertilized eggs developing into larvae. Buds form from the stolons. Colonies vary in size, and can range from small clusters of zooids to huge spreading masses. The zooids are hermaphroditic, with eggs and sperm being released to the atrial chamber. Eggs may be self-fertilized or fertilized by sperm from nearby animals, but some species have a partial block to self-fertilization. Embryos are incubated within the atrial chamber, and hatch into tadpole larvae, with a muscular tail and a notochord, eyespots, and a set of adhesive papillae. The lecithotrophic (non-feeding, yolk-dependent) larvae are expelled on hatching, and swim briefly before settlement. Swimming periods are usually less than a day, and some larvae can settle immediately after release, but the larval period can be longer at lower temperatures. On settlement, the tail is absorbed, the gill basket expands, and the tunicate begins to feed by filtering (Van Name 1945; Barnes 1983).

Food:

Phytoplankton, detritus

Trophic Status:

Suspension Feeder

SusFed

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Habitats

General Habitat	Marinas & Docks	None
General Habitat	Coarse Woody Debris	None
General Habitat	Rocky	None
Salinity Range	Polyhaline	18-30 PSU
Salinity Range	Euhaline	30-40 PSU
Tidal Range	Subtidal	None
Vertical Habitat	Epibenthic	None

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Tolerances and Life History Parameters

Maximum Length (mm)	None	4 mm (zooids)
Broad Temperature Range	None	Cold temperate-Warm temperate
Broad Salinity Range	None	Polyhaline-Euhaline

General Impacts

In Japan, where Perophora japonica is native, it has been reported to foul cultured oysters (Arakawa 1990, cited by da Rocha et al. 2009); however, no impacts have been reported from introduced populations.

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Regional Impacts

NEA-III	None		Economic Impact	Fisheries
Fouling of cultured mussels by a variety of non-native tunicates was reported beginning in 2013, and was a serious problem by 2016 (Palanisamy et al. 2018).

References

Abbott, Donald P.; Lambert, Charles C.; Lambert, Gretchen; Newberry, A. Todd (2007) The Light and Smith Manual: Intertidal Invertebrates from Central California to Oregon (4th Edtion), University of California Press, Berkeley, CA. Pp. 949-964

Bancila. Raluca I.; Skolka, Marius; Ivanova, Petya; Surugiu, Victor; Stefanova, Kremena; Todorova. Valentina; Zenetos, Argyro (2022) Alien species of the Romanian and Bulgarian Black Sea coast: state of knowledge, uncertainties, and needs for future research, Aquatic Invasions 17: Published online

Barnes, Robert D. (1983) Invertebrate Zoology, Saunders, Philadelphia. Pp. 883

Bishop, John D. D.; Wood, Christine A.; Lévêque, Laurent; Yunnie, Anna L. E.; Viard, Frédérique (2015b) Repeated rapid assessment surveys reveal contrasting trends in occupancy of marinas by non-indigenous species on opposite sides of the western English Channel, Marine Pollution Bulletin 95: 699-706

Bishop, John D.D.; Wood, Christine A.; Yunnie, Anna L. E.; Griffiths, Carly A. (2015a) Unheralded arrivals: non-native sessile invertebrates in marinas on the English coast, Aquatic Invasions 10: 249-264

California Department of Fish and Wildlife (2014) Introduced Aquatic Species in California Bays and Harbors, 2011 Survey, California Department of Fish and Wildlife, Sacramento CA. Pp. 1-36

da Rocha, Rosana M.; Kremer, Laura P.; Baptista, Mariah S.; Metri, Rafael (2009) Bivalve cultures provide habitat for exotic tunicates in southern Brazil., Aquatic Invasions 4(1): 195-205

El Nagar, Aliya; Huys, Rony; Bishop, John D. D. (2010) Widespread occurrence of the Southern Hemisphere ascidian Corella eumyota Traustedt, 1882 on the Atlantic coast of Iberia, Aquatic Invasions 5(2): 169-173

Gittenberger, Adriaan (2007) Recent population expansions of non-native ascidians in the Netherlands., Journal of Experimental Marine Biology and Ecology 342: 122-126

Gittenberger, Adriaan (2009) Invasive tunicates on Zeeland and Prince Edward Island mussels, and management practices in The Netherlands., Aquatic Invasions 4(1): 279-281

Goulletquer, Philippe; Bachelet, Guy; Sauriau, Pierre; Noel, Pierre (2002) Invasive aquatic species of Europe: Distribution, impacts, and management, Kluwer Academic Publishers, Dordrecht. Pp. 276-290

Hedge, Luke H.; Johnston, Emma L. (2012) Propagule pressure determines recruitment from a commercial shipping pier, Biofouling 28(1): 73-85

Lambert, Gretchen (2005) First North American record of the ascidian Perophora japonica., Journal of the Marine Biological Association of the United Kingdom 85(4): 1011-1012

Liu, Wenliang; Liang, Xiaoli ; Zhu, Xiaojing (2015) A new record and mitochondrial identification of Synidotea laticauda Benedict, 1897 (Crustacea: Isopoda: Valvifera: Idoteidae) from the Yangtze Estuary, China, Zootaxa 4294: 371-380

Locke, Andrea (2009) A screening procedure for potential tunicate invaders of Atlantic Canada., Aquatic Invasions 4(1): 71-79



Nichols, Claire L.; Lambert, Gretchen; Nydam, Marie L. (2023) Continued persistence of non-native ascidians in Southern California harbors and marinas, Aquatic Invasions 18(1): 1-22
https://doi.org/10.3391/ ai.2023.18.1.101962

Nishikawa, Teruaki; Bishop, John D. D.; Sommerfeldt, A. Dorothes (2000) Occurrence of the alien ascidian, Perophora japonica at Plymouth., Journal of the Marine Biological Association 80(5): 955-956

Nishikawa, Teruki (1991) The Ascidians of the Japan Sea., Publication of the Seto Marine Biological Laboratory 35(1/3): 25-170

Nunn, Julia; Minchin, Dan 2013 Marine non-native invasive species in Northern Ireland. <missing URL>



Pérez-Portela, R.; Turon, X.; Bishop, J. D. (2012) Bottlenecks and loss of genetic diversity: spatio-temporal patterns of genetic structure in an ascidian recently introduced in Europe, Marine Ecology Progress Series 451: 93-105

Rho, Boon Jo (1995) The Ascidians (Tunicata) from Chindo Islands, Korea, Korean Journal of Systematic Zoology 11(1): 125-145

Rho, Boon Jo; Lee, Ji-Eun (1991) A systematic study of the Ascidians in Korea, Korean Journal of Systematic Zoology 7(2): 195-220

Ribeiro, Romeu S.; Mata, Ana M. T. ; Salgado, Ricardo; Gandra, Vasco; Afonso, Inês; Galhanas, Dina; Dionísio, Maria Ana; Chainho, Paula (2023) Undetected non-indigenous species in the Sado estuary (Portugal), a coastal system under the pressure of multiple vectors of introduction, Journal of Coastal Conservation 27(53): Published online
https://doi.org/10.1007/s11852-023-00979-3

Ruiz, Gregory M.; Geller, Jonathan (2018) Spatial and temporal analysis of marine invasions in California, Part II: Humboldt Bay, Marina del Re, Port Hueneme, and San Francisco Bay, Smithsonian Environmental Research Center & Moss Landing Laboratories, Edgewater MD, Moss Landing CA. Pp. <missing location>

Sanamyan, Karen (1998) Ascidians from the North-Western Pacific region. 5. Phlebobranchia, Ophelia 49(2): 97-116

Simkanin, Christina; Fofonoff, Paul W.; Larson, Kriste; Lambert, Gretchen; Dijkstra, Jennifer A.; Ruiz, Gregory M. (2016) Spatial and temporal dynamics of ascidian invasions in the continental United States and Alaska, Marine Biology 163: Published online

Van Name, Willard G. (1945) The North and South American ascidians, Bulletin of the American Museum of Natural History 84: 1-462

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