Invasion History

First Non-native North American Tidal Record: 1961
First Non-native West Coast Tidal Record:
First Non-native East/Gulf Coast Tidal Record: 1961

General Invasion History:

Ecteinascidia turbinata is found in Bermuda, the reefs off the Carolinas, the coast of Florida, the Caribbean, the Gulf of Mexico (Bingham and Young 1987; Calder et al. 1966; Van Name 1945), the Mediterranean, and the tropical East Atlantic (Senegal, Cape Verde Islands) (Monniot and Monniot 1994; Carballo 2000). The genetic similarity of populations on both sides of the Atlantic raises the possibility that populations may have been transported across the Atlantic by ship. However, it is not clear to which side of the Atlantic it is native (Monniot and Monniot 1994; Lopez-Legentil and Turon 2007). Ecteinascidia turbinata was introduced north of Cape Hatteras, North Carolina in 1960 at Wachapreague, Virginia (US National Museum of Natural History 2008) and the York River near Gloucester Point (Calder et al. 1966).

North American Invasion History:

Invasion History on the East Coast:

Ecteinascidia turbinata was collected by dredge in the channel at the mouth of the York River, Virginia in August 1966 (Calder et al. 1966) and again in 1967 and 1971 (Calder, in Wass 1972). There have been no more recent reports of this species in Chesapeake Bay proper, however, it was collected in Wachapreague, VA in 1961 (1961, USNM 17042, US National Museum of Natural History 2008) and is established there (Joao Canning-Clode, personal communication). It is also established in Chincoteague Bay (collected in 1996-1998, Prezant et al. 2002). Calder et al. (1966) considered this species to be a probable introduction to the Chesapeake Bay because 'Existing currents are not conducive to the transport of southern species into Chesapeake Bay'. Waters adjacent to the Virginia coast (Virginia Coastal Current) move southward (Ford and Miller 1952) and the Gulf Stream moves northeastward and away from Chesapeake Bay. Because it is known to foul floats and test surfaces in the Florida region (Woods Hole Oceanographic Institution; 1952) it could attach to ships, and may have been introduced into Chesapeake Bay in this fashion (Calder et al. 1966).


Ecteinascidia turbinata is a colonial tunicate that typically grows as a dense cluster of elongate, somewhat club-shaped zooids, each with its own separate test. The zooids are connected at their tapering bases by a network of stolons that adhere to the surface of the substrate (mangroves, seagrass) on which the colony grows. Colonies often surround mangrove roots or seagrass blades (Van Name 1945).

Zooids are oblong and truncate at the anterior end where the two apertures are located and taper at the other end to a narrow pedicel containing the vessel that connects to the rest of the colony. The zooids are about 20 mm long or less, occasionally larger. The apertures are located on short siphons or slight elevations, which often do not project beyond the surface of the test. The apertures have thin margins, varying from smooth to sinuous. The oral aperture is larger and a little further anterior than the atrial. The oral tentacles are threadlike and quite numerous. Large individuals (~20 mm) have about 30-40 tentacles that are arranged with considerable regularity. The branchial sac is long, and barrel shaped, with about 27-30 rows of about 60 small, oval, or elongate stigmata. The stomach is elliptical and joins an intestinal loop which ends dorsally around the 10th row of stigmata. The reproductive organs are located in the bend of the intestinal loop. The test is transparent and colorless, thicker on the ends of the body. The mantle and internal organs are also very transparent, but in the living and fresh specimens, the translucency shades into yellow, orange, or pink on the anterior part of the body. The intestinal loop is colored yellow or orange (Van Name 1945).


Taxonomic Tree

Kingdom:   Animalia
Phylum:   Chordata
Subphylum:   Tunicata
Class:   Ascidiacea
Order:   Phlebobranchia
Family:   Perophoridae
Genus:   Ecteinascidia
Species:   turbinata


Ascidia claviformis (Leseur, 1823)
Ecteinascidia moorei (Herdman, 1891)

Potentially Misidentified Species



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).



Trophic Status:

Suspension Feeder



General HabitatGrass BedNone
General HabitatCoarse Woody DebrisNone
General HabitatUnstructured BottomNone
General HabitatMarinas & DocksNone
General HabitatMangrovesNone
General HabitatCoral reefNone
Salinity RangePolyhaline18-30 PSU
Salinity RangeEuhaline30-40 PSU
Tidal RangeSubtidalNone
Tidal RangeLow IntertidalNone
Vertical HabitatEpibenthicNone

Tolerances and Life History Parameters

Maximum Temperature (ºC)32Field temperature, Indian River Lagoon FL (Vazquez and Young 2000).
Minimum Salinity (‰)22Field data, York River VA (Calder et al. 1966); Experimental, larval metamorphosis and juvenile survival (Vazquez and Young 2000).
Maximum Salinity (‰)40Field data, Isla de Formentura, Mediterranean, Spain (Carballo 2000)
Minimum Reproductive Salinity22Experimental, larval metamorphosis and juvenile survival (Vazquez and Young 2000).
Minimum Duration0Field data, larval time from release to settlement, FL (Bingham and Young 1991).
Maximum Duration0Field data, larval time from release to settlement, FL (Bingham and Young 1991).
Broad Temperature RangeNoneWarm temeprate-Tropical
Broad Salinity RangeNonePolyhaline-Euhaline

General Impacts

Ecteinascidia turbinata is an abundant and important organism in tropical and subtropical Atlantic mangrove and seagrass habitats. However, impacts of its invasion in the Chesapeake and Chincoteague Bays have not been reported.

Regional Distribution Map

Bioregion Region Name Year Invasion Status Population Status
NA-ET4 Bermuda 1880 Crypto Estab
CAR-I Northern Yucatan, Gulf of Mexico, Florida Straits, to Middle Eastern Florida 1902 Crypto Estab
CAR-V None 1921 Crypto Estab
MED-IV None 1973 Crypto Estab
CAR-II None 1897 Crypto Estab
CAR-VII Cape Hatteras to Mid-East Florida 0 Crypto Estab
NA-ET3 Cape Cod to Cape Hatteras 1961 Def Estab
CAR-IV None 1884 Crypto Estab
MED-II None 0 Crypto Estab
MED-III None 1973 Crypto Estab
WA-I None 1949 Crypto Estab
WA-VI None 1906 Crypto Estab
CAR-III None 0 Crypto Estab
CAR-VI None 1958 Crypto Estab
MED-V None 0 Crypto Estab
MED-VI None 2011 Crypto Estab
M130 Chesapeake Bay 1966 Def Unk
NEA-V None 0 Crypto Estab
M120 Chincoteague Bay 1996 Def Estab
M128 _CDA_M128 (Eastern Lower Delmarva) 1961 Def Estab
CIO-II None 2015 Def Unk

Occurrence Map

OCC_ID Author Year Date Locality Status Latitude Longitude


Abdelsalam, Khaled Mahmood (2018) First record of the exotic lysmatid shrimp Lysmata vittata (Stimpson, 1860) (Decapoda: Caridea: Lysmatidae) from the Egyptian Mediterranean coast, Mediterranean Marine Science 19(1): 124-131

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

Bingham, Brian L.; Young, Craig M. (1991) Larval behavior of the ascidian Ecteinascidia turbinata Herdman; an in situ experimental study of the effects of swimming on dispersal, Journal of Experimental Marine Biology and Ecology 145: 189-204

Calder, Dale R.; Thornborough, John R.; Lowry, James K. (1966) Record of Ecteinascidia turbinata (Ascidiacea, Perphoridae) in the York River., Chesapeake Science 7: 223-224

Canning-Clode, João; Fofonoff, Paul; Riedel, Gerhardt F.; Torchin, Mark; Ruiz, Gregory M. (2011) The effects of copper pollution on fouling assemblage diversity: A tropical-temperate comparison, PLOS ONE 6(3): e18026

Carballo, Jose Luis (2000) Larval ecology of an ascidian tropical population in a Mediterrean enclosed ecosystem., Marine Ecology Progress Series 195: 159-167

da Rocha, Rosa Morales and 13 authors (2010) Inventory of ascidians (Tunicata, Ascidiacea) from the National Park La Restinga, Isla Margarita, Venezuela, Biota Neotropica 10: published online

Goodbody, Ivan; Cole, Linda (2006) The tropical Western Atlantic Perophoridae (Ascidiacea) II. The Genus Ecteinascidia, Bulletin of Marine Science 79(1): 49-70

Gravili, Cinzia; Ambrosio, Paolo D.; di Camillo, Cristina, Renna, Giuseppina; Bouillon, Jean; Boero, Ferdinando (2008) Clytia hummelincki (Hydroidomedusae: Leptomedusae) in the Mediterranean Sea, Journal of the Marine Biological Association of the United Kingdom 88(8): 1547–1553

Hernandez-Zanuy, Aida; Carballo, Jose Luis; Garcia-Cadige, Alida; Naranjo, Santiago; Esquivel, Maecario (2007) [Distribution and abundance of Ecteinascida turbinata (Ascidiacea: Perophoridae) in Cuba], Revista de Biologia Tropical 55(1): 247-254

Kaplan, Eugene H. (1988) A Field Gude to Southeastern and Caribbean Seashores, In: (Eds.) . , Boston. Pp. <missing location>

Koukouras, Athanasios; Voultisiado-Koukoura, Eleni; Kevrekidis, Theodoros; Vafidis, Dimitri (1995) Ascidian fauna of the Aegean Sea with a checklist of the Mediterranean and Black Sea species, Annales de l Institut Oceanographique, Paris 71(1): 19-34

Lopez-Legentil, Susanna: Turon, Xavier (2007) Lack of genetic variation in mtDNA sequences over the amphiatlantic distribution range of the ascidian Ecteinascidia turbinata., Molecular Phylogenetics and Evolution 45: 405-408

Millar, R.H. (1978) Ascidians from the Guyana shelf., Journal of Sea Research 32(1): 99-106

Monniot, Claude; Monniot, Francoise (1994) Additions to the inventory of Eastern tropical Atlantic Ascidians: arrival of cosmopolitan species., Bulletin of Marine Science 54(1): 71-93

Moura, Carlos J.; Collins, Allen G.; Santos, Ricardo S.; Lessios, Harilaos (2019) Predominant east to west colonizations across major oceanic barriers: Insights into the phylogeographic history of the hydroid superfamily Plumularioidea, suggested by a mitochondrial DNA barcoding marker, Ecology and Evolution 9: :13001–13016.
DOI: 10.1002/ece3.5608

Prezant, Robert; Counts, Clement L.; Chapman, Eric J. (2002) Mollusca of Assateague Island, Maryland and Virginia: additions to the fauna, range extensions, and gigantism., Veliger 45: 337-355

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

Thessalou-Legaki, M. and 38 authors (2012) New Mediterranean biodiversity records (December 2012), Mediterranean Marine Science 13(2): 312-327

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

Van Name, Willard G. (1921) Ascidians of the West Indian region and southeastern United States., Bulletin of the American Museum of Natural History 44: 283-494

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

Vazquez, Elsa; Young, Craig M. (2000) Effects of low salinity on metamorphosis in estuarine colonial ascidians, Invertebrate Biology 119(4): 433-444

Wass, Melvin L. (1972) A checklist of the biota of lower Chesapeake Bay, Special Scientific Report, Virginia Institute of Marine Science 65: 1-290

Young, C. M.; Bingham, B. L. (1987) Chemical defense and aposematic coloration in larvae of the ascidian Ecteinascidia turbinata, Marine Biology 96: 539-544