Trididemnum orbiculatum

Invasion History

First Non-native Panama (Pacific) Tidal Record: 2009

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Panama Invasion History:

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Invasion history elsewhere in the world:

None

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Description

Trididemnum orbiculatum grows in thin, flat colonies, up to 25-30 mm across, and less than 2 mm thick. In fresh specimens, the surface of the colony issmooth, with the zooids covered by dense layer of spicules, with a more transparent circular area over each zooid, and more spicules in between. The spicukes are about 0.04 mm in diameter, with multiple conical points. Thr zooids are about 1 mm in diameter. The branchial orifice has 6 lobes, while the atiail opening is plain, and located further down the thorax . The middle portion of the thorax is quite constricted, with a long muscular process extending tow the common test of the colony. The openings have strong sphincters, and lomgitudinal muscles, which can contract the thorax

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Taxonomy

Ecology

Food:

Phytoplankton, detritus

Trophic Status:

Suspension Feeder

SusFed

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Habitats

General Habitat	Marinas & Docks	None
General Habitat	Coral reef	None
General Habitat	Rocky	None
General Habitat	Oyster Reef	None
Tidal Range	Subtidal	None
Vertical Habitat	Epibenthic	None

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Tolerances and Life History Parameters

Broad Temperature Range	None	Subtropical-Tropical
Broad Salinity Range	None	Polyhaline-Euhaline

General Impacts

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References

Berrill, N. J. (1932) Ascidians of the Bermudas, Biological Bulletin 62(1): 77-88

Carman, Mary R. and 7 authors 2010 Ascidians at the Pacific and Atlantic entrances to the Panama Canal. <missing URL>



Carman, Mary, and 8 authors (2011) Ascidians at the Pacific and Atlantic entrances to the Panama Canal, Aquatic Invasions 6(4): 371-380

da Rocha, Rosana M.; Faria, Suzana B.; Moreno, Tatiane R. (2005) Ascidians from Bocas del Toro, Panama, Caribbean Journal of Science 41(3): 600-612

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

da Rocha, Rosana M.; Moreno, Tatiane M.; Metri, Rafael (2005) [Ascidians of the Marine Biological Reserve of Avoredro, Santa Catarina, Brazil)., Revista Brasileira de Zoologia 22(2): 461-476

Dias, Gustavo Muniz; Abreu, Aluana Gonçalves; Morais e Silva, Fábio de Oliveira; Solferini, Vera Nisaka (2009) Microgeographical differentiation between morphotypes of Trididemnum orbiculatum (Tunicata: Ascidiacea) in southeastern Brazil, Aquatic Biology 4: 243-252

Millar, R. H. (1962) Some Ascidians from the Caribbean, Studies of the Fauna of Curacao and other Caribbean Islands 59: 61-77

Monniot, C.; Monniot, F. (1985) [Littoral ascidians of Guadeloupe Island: IX. Characteristics of populations, ecology, relationships with the world fauna] (French), Tethys 11(3-4): 203-213

Monniot, Françoise (1983) [littoral ascidians of guadeloupe. i. didemnidae] (french), Bulletin du Museum National d'Histoire Naturelle. 4e Serie. Section A. Zoologie, Biologie et Ecologie Animales 5(1): 5-49

U.S. National Museum of Natural History 2002-2021 Invertebrate Zoology Collections Database. http://collections.nmnh.si.edu/search/iz/



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

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