Conopeum tenuissimum

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:

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General Invasion History:

Conopeum tenuissimum is an encrusting bryozoan occurring on docks, pilings, breakwaters, oysters, seagrasses, and other surfaces in estuarine habitats. It is native to the Northwestern Atlantic, where it occurs from Great Bay, New Hampshire and Boston Harbor to the Gulf of Mexico and Lake Maracaibo, Venezuela (Osburn 1944; Maturo 1958; Wass 1972; Dudley 1973; Winston 1977; Winston 1982; MIT Sea Grant 2003; Ruiz et al., unpublished data).

North American Invasion History:

Invasion History on the West Coast:

Conopeum tenuissimum was first identified from San Francisco Bay by Patricia L. Cook based on material collected in the estuarine Lake Merritt, Oakland, California (Carlton 1979; Cohen and Carlton 1995) in 1962 (J.T. Carlton, personal communication, 2013). It is likely that earlier records of brackish water Conopeum in the Bay, such as that of Filice (1959, as Conopeum commensale) are C. tenuissimum. It was probably introduced in the 19th century with oysters from the East Coast (Carlton 1979). It ranges from the central Bay (Oakland and the Presidio Yacht Club) to Carquinez Straits, at the head of San Pablo Bay, and well into brackish waters on the Petaluma River (Cohen and Chapman 2005; Cohen et al. 2005).

This bryozoan is also established in Elkhorn Slough, where it was found during a 1998 survey (Wasson et al. 2001). A bryozoan identified as ‘possibly C. tenuissimum’ was found in 'marinas around the bay' in Humboldt Bay in 2000 (Boyd et al. 2002). In Coos Bay, Oregon, C. tenuissimum was first collected in 1970, and is now common in the estuary (Carlton 1989; de Rivera et al. 2005).

Invasion History Elsewhere in the World:

Conopeum tenuissimum is established in estuaries in Nigeria and Ghana, in West Africa (Cook 1968; Cook 1985) and in Port Hacking, in Sydney Harbor, Australia (Vail and Wass 1981; Australian Museum Business Services 2002). 

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Description

Colonies of Conopeum tenuissimum form lacy white crusts on seagrasses, oysters, docks, pilings, breakwaters and other hard substrates. Sometimes colonies are pink or tan, due to food in the intestine or sediment caught in the spines. Colonies vary greatly in size and shape depending on the type of substratum. Zooids are typically 530 µm X 250 µm, and elongate-oval in shape. There is a single pair of spines at the distal end of the zooid, and 5-7 pairs of lateral spines. The polyps have ~11-15 tentacles. The budding pattern in Florida populations is that the ancestrula produces one distal primary bud, followed by proximal secondary buds, so that the colony initially develops a 'double-fan' pattern spreading from the two ends of the ancestrula. This eventually develops into a circular pattern as the colony grows. Compared to specimens from Florida identified as C. seurati, C. tenuissimum has larger zooids, and a more regular colony arrangement, heavier calcification, and more lateral spines (description from: Osburn 1944; Winston 1982; Winston and Hayward 2012). Conopeum is a difficult genus, and identifications of C. tenuissimum are frequently somewhat tentative (Cohen and Carlton 1995, Linda McCann, personal communication, 2011).

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Taxonomy

Ecology

General:

Life History- Conopeum tenuissimum is an encrusting, calcified bryozoan colony composed of many individual zooids. The zooids feed by extending the ciliated tentacles of the lophophore as a funnel, creating a current, and driving food particles into their mouths. The food is guided along the tentacles and through the pharynx by the cilia. Larger food particles can be moved or captured by flicking or contracting the tentacles (Barnes 1983). Larvae of C. tenuissimum are planktotrophic, but probably have a shorter planktonic period than Membranipora spp. (Dudley 1973; Winston and Hayward 2012). Larvae settle on a substrate and metamorphose into the first zooid of a colony, an ancestrula (Dudley 1973; Barnes 1983).

Ecology- Conopeum tenuissimum is common in brackish water (Osburn 1944) and is known from eelgrass beds, oyster beds, pilings, shells and pebbles (Osburn 1944; Dudley 1973; Winston 1982).

Food:

Phytoplankton

Trophic Status:

Suspension Feeder

SusFed

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Habitats

General Habitat	Coarse Woody Debris	None
General Habitat	Grass Bed	None
General Habitat	Oyster Reef	None
General Habitat	Marinas & Docks	None
General Habitat	Rocky	None
Salinity Range	Mesohaline	5-18 PSU
Salinity Range	Polyhaline	18-30 PSU
Salinity Range	Euhaline	30-40 PSU
Tidal Range	Subtidal	None
Tidal Range	Low Intertidal	None
Vertical Habitat	Epibenthic	None

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Tolerances and Life History Parameters

Minimum Salinity (‰)	6	Field data (Osburn 1944)
Maximum Salinity (‰)	37	Field data (Cook 1985)
Broad Temperature Range	None	Cold temperate-Tropical
Broad Salinity Range	None	Mesohaline-Euhaline

General Impacts

Conopeum tenuissimum is a common fouling organism in its introduced range, including San Francisco Bay, Coos Bay, and Sydney Harbor (Vail and Wass 1981; Carlton 1989; Cohen and Carlton 1995), but specific economic or ecological impacts have not been reported.

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References

Australian Museum Business Services (2002) <missing title>, Australian Museum Business Services, for Sydney Ports Corporation, Sydney. Pp. <missing location>

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

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

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

Carlton, James T. (1979) History, biogeography, and ecology of the introduced marine and estuarine invertebrates of the Pacific Coast of North America., Ph.D. dissertation, University of California, Davis. Pp. 1-904

Carlton, James T. (1989) <missing title>, <missing publisher>, <missing place>. Pp. <missing location>

Cohen, Andrew N. and 10 authors (2005) <missing title>, San Francisco Estuary Institute, Oakland CA. Pp. <missing location>

Cohen, Andrew N.; Carlton, James T. (1995) Nonindigenous aquatic species in a United States estuary: a case study of the biological invasions of the San Francisco Bay and Delta, U.S. Fish and Wildlife Service and National Sea Grant College Program (Connecticut Sea Grant), Washington DC, Silver Spring MD.. Pp. <missing location>

Cohen, Andrew N.; Chapman, John T. (2005) <missing title>, San Francisco Estuary Institute, San Francisco. Pp. <missing location>

Cook, P. L. (1985) Bryozoa from Ghana, Zoologische Wetenschappen 238: <missing location>

Cook, Patricia L. (1968) Bryozoa (Polyzoa) from the coasts of tropical West Africa, Atlantide - Report 10: 115-262

de Rivera, Catherine, and 27 authors (2005) Broad-scale non-indigenous species monitoring along the West Coast in National Marine Sanctuaries and National Estuarine Research Reserves report to National Fish and Wildlife Foundation, National Fish and Wildlife Foundation, Washington, D.C.. Pp. <missing location>

Dudley, J. E. (1973) A note on the taxonomy of three membraniporine ectoprocts from Chesapeake Bay, Chesapeake Science 14: <missing location>

Dudley, Judith E. (1973) Observations on the reproduction, early larval development, and colony astogeny of Conopeum tenuissimum (Canu), Chesapeake Science 14(4): 270-278

Green, Stephanie J. and 7 authors (2021) Broad-scale acoustic telemetry reveals long-distance movements and large home ranges for invasive lionfish on Atlantic coral reefs, Marine Ecology Progress Series 673: 117-134

Maturo, Frank J. S., Jr. (1957) A study of the Bryozoa of Beaufort, North Carolina and vicinity, Journal of the Elisha Mitchell Scientific Society 72(1): 11-68

MIT Sea Grant 2003-2008 Introduced and cryptogenic species of the North Atlantic. <missing URL>



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Vail, Lyle L.; Wass, Robin E. (1981) Experimental studies on the settlement and growth of Bryozoa in the natural environment., Australian Journal of Marine and Freshwater Research 32: 639-656

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Wasson, Kerstin; Zabin, C. J.; Bedinger, L.; Diaz, M. C.; Pearse J. S. (2001) Biological invasions of estuaries without international shipping: the importance of intraregional transport, Biological Conservation 102: 143-153

Winston, Judith E. (1977) Distribution and ecology of estuarine ectoprocts: a critical review., Chesapeake Science 18(1): 34-57

Winston, Judith E. (1982) Marine bryozoans (Ectoprocta) of the Indian River area (Florida)., Bulletin of the American Museum of Natural History 173: 99-176

Winston, Judith E. (1995) Ectoproct diversity of the Indian River coastal lagoon, Bulletin of Marine Science 57(1): 84-93

Winston, Judith E.; Hayward, Peter J. (2012) The marine bryozoans of the northeast coast of the United States: Maine to Virginia, Virginia Museum of Natural History Memoir 11: 1-180

Wonham, Marjorie J.; Carlton, James T. (2005) Trends in marine biological invasions at local and regional scales: the Northeast Pacific Ocean as a model system, Biological Invasions 7: 369-392

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