Diadumene lineata is commonly known as the Orange-Striped Anemone. It is believed to be native to the Northwest Pacific including Japan and Hong Kong. It has successfully invaded coastal waters in many regions around the world, including Europe, the Mediterranean Sea, the Black Sea, the Canary Islands, Malaysia, New Zealand, Hawaii, Argentina and the East, Gulf and West Coasts of North America. It is known mostly from estuaries and sheltered waters, where it grows on oysters, rocks, seaweeds, pilings, and floats. No economic or ecological impacts have been reported for this species.
Image Credit: Melissa Frey, Royal BC Museum
|Bioregion||Region Name||Year||Invasion Status||Population Status|
|NA-ET3||Cape Cod to Cape Hatteras||1892||Def||Estab|
|NA-ET2||Bay of Fundy to Cape Cod||1899||Def||Estab|
|CAR-VII||Cape Hatteras to Mid-East Florida||1929||Def||Estab|
|CAR-I||Northern Yucatan, Gulf of Mexico, Florida Straits, to Middle Eastern Florida||1948||Def||Estab|
|NEP-III||Alaskan panhandle to N. of Puget Sound||1909||Def||Estab|
|NEP-IV||Puget Sound to Northern California||1947||Def||Estab|
|NEP-V||Northern California to Mid Channel Islands||1906||Def||Estab|
|NEP-VI||Pt. Conception to Southern Baja California||1956||Def||Estab|
|G310||Corpus Christi Bay||1948||Def||Estab|
|M060||Hudson River/Raritan Bay||1972||Def||Estab|
|M040||Long Island Sound||1892||Def||Estab|
|P050||San Pedro Bay||1973||Def||Estab|
|P020||San Diego Bay||1996||Def||Estab|
|P090||San Francisco Bay||1906||Def||Estab|
|P112||_CDA_P112 (Bodega Bay)||1956||Def||Estab|
|P292||_CDA_P292 (San Juan Islands)||1977||Def||Estab|
|P293||_CDA_P293 (Strait of Georgia)||1998||Def||Estab|
|S140||St. Catherines/Sapelo Sounds||2000||Def||Estab|
|S056||_CDA_S056 (Northeast Cape Fear)||1978||Def||Estab|
|S070||North/South Santee Rivers||1978||Def||Estab|
|S076||_CDA_S076 (South Carolina Coastal)||1978||Def||Estab|
|S090||Stono/North Edisto Rivers||1978||Def||Estab|
|S100||St. Helena Sound||1978||Def||Estab|
|N180||Cape Cod Bay||2000||Def||Estab|
|N040||Blue Hill Bay||1949||Def||Estab|
|P093||_CDA_P093 (San Pablo Bay)||1906||Def||Estab|
|NA-ET1||Gulf of St. Lawrence to Bay of Fundy||2013||Def||Estab|
Diadumene lineata has a column which is about one-third as wide as the height when extended. The largest specimens reach 31 mm in height and 22 mm width at the base (Hand 1955, California). This anemone has acontia, threadlike structures, lined with cnidocytes (cells bearing nematocysts) which extend from the middle lobes of incomplete mesenteries, which partially divide the gastrovascular cavity. The acontia can be extended into the body cavity, or extruded through pores, as a defense in response to disturbance or handling. There are 50-100 tentacles, and there is a substantial tentacle-free zone around the mouth. The tentacles are long and slender, when extended. There is considerable color variation in this anemone. The column can be dark-to-olive brown, greenish brown, olive-green, or gray-green, without stripes, or with white or orange-red stripes. The tentacles are usually translucent, but may be gray or light green (description from: Field 1949; Hand 1955; Gosner 1978; Fautin, in Carton 2007).
Diadumene lineata is believed to be native to the Northwest Pacific including Japan and Hong Kong (where it was described by Verrill in 1870, as Sagartia lineata) (Uchida 1932; Stephenson 1935). In 1892, it was found in Long Island Sound at New Haven, Connecticut, where Verrill described it again, as S. luciae (Verrill 1898). This anemone has successfully invaded coastal waters in many regions, including the Atlantic, Mediterranean, and Black Sea coasts of Europe (Stephenson 1935; Preda et al. 2012); the Canary Islands (Ocaña and den Hartog 2002); Malaysia (Dunn 1982); New Zealand (Cranfield et al. 1998); Hawaii (Zabin et al. 2004); the West Coast of North America (Vancouver Island to San Diego; Carlton 1979); and the coast of Argentina (Molina et al. 2008). Introduced populations of this anemone primarily reproduce asexually (Shick et al. 1979; Ting and Geller 2000), so the most likely vectors are hull fouling or oyster shipments (Visscher 1927; Shick et al. 1979; Gollasch and Riemann-Zurneck 1996), but not as larvae in ballast water. The clonal nature of its reproduction, resulting in low genetic diversity, may contribute to a pattern of sudden mass disappearances in response to severe weather or other disturbances, and rapid recolonization, often several years later (Parker 1919; Stephenson 1935; Shick and Lamb 1977; Carlton 1979).
On the West Coast, the earliest records of D. lineata are from San Francisco Bay in 1906, and the east coast of Vancouver Island (Hargitt 1914, McMurrich 1921, both cited by Carlton 1979). Multiple introductions by shipping and oysters (both Atlantic and Pacific are likely; Carlton 1979; Ting and Geller 2000). This anemone has been found in most West Coast embayments receiving commercial shipping: Puget Sound, Washington (WA) (date unspecified, Ricketts and Calvin 1939, cited by Carlton 1979); Coos Bay, Oregon (in 1947, Carlgren 1953, cited by Carlton 1979); Humboldt Bay, California (CA) (in 1974, Carlton 1979); San Francisco Bay, CA (in 1906, Hargitt 1914, cited by Carlton 1979); San Diego Bay, CA (in 1927, no further records until 1979, Cohen 2005; Crooks 1998). It is also found in many smaller embayments where oysters have been planted and cultured, as well as those receiving only recreational and fishing boat traffic , including: Padilla Bay, WA (in 1998, Cohen et al. 1998); Willapa Bay, WA (Long 1967, cited by Carlton 1979); Bodega Harbor, CA (Hand 1956, cited by Carlton 1979); Tomales Bay, CA (Hand 1956, cited by Carlton 1979); Elkhorn Slough, CA (Ricketts and Calvin 1938, cited by Carlton 1979); Huntington Harbor-Anaheim Bay, CA (Williams 1973, cited by Carlton 1979); Newport Bay, CA (Hand 1956, cited by Carlton 1979); Mission Bay, CA (in 1996, Crooks 1998). In southern California, D. lineata's status is a little uncertain. In the 1970s, it was reported from Huntington Harbor-Anaheim Bay in one survey (Williams 1973, cited by Carlton 1979), but was not found in other collections at the same location. It was reported from San Diego Bay in 1927, but was not seen again for about 50 years (Crooks 1998; Cohen 2005), suggesting possible extinction and recolonization. In San Francisco Bay, D. lineata occurs in a wide range of habitats, including fouling communities and brackish marsh channels in San Pablo, Central, and South San Francisco Bay, but is not found in the more saline and colder waters near the mouth of the Bay (Carlton 1979; Cohen and Carlton 1995; Cohen 2005; Cohen et al. 2005).
Diadumene lineata was first collected in New Haven, Connecticut in 1892 and described as 'Sagartia luciae'. It had become much more abundant by 1898 (Verrill 1898). It spread rapidly northward, reaching Narragansett Bay in 1895, Woods Hole in 1898, and Massachusetts Bay, at Nahant, Massachusetts in 1899 (Parker 1902). Shick reported it as occurring on the 'entire Maine Coast' before 1975. However, a population at Blue Hill Falls, ME, on the basis of morphological features, appears to be a separate introduction, possibly brought with an unsuccessful planting of Japanese oysters in 1949. Northern records include Cobscook Bay, Maine (Trott 2004); Sam Orr's Pond, Passamaquoddy Bay, New Brunswick (2009, Saunders et al. 2013, extinct in 2017-2018, Ma et al. 2020); and Halifax Harbour, Nova Scotia (Moore et al. 2014, Ma et al. 2020). Information on its southward spread is a little spottier. It was found at the mouth of Chesapeake Bay and near Beaufort, North Carolina by 1929 (Richards 1929; Pearse 1936), but wasn't reported from the Hudson estuary until 1972 (Ristich et al. 1977). In Chesapeake Bay, and presumably other estuaries, it occurs primarily in the lower, more saline, portion, just reaching Maryland waters at the mouth of the Patuxent River (Merrill and Boss 1966). It is common 'in most inshore areas' in South Carolina (Calder and Hester 1978), and has been found in St. Catherines Sound, Georgia, and near Cape Canaveral, Florida at Mosquito Lagoon (Boudreaux et al. 2006).
Diadumene lineata was first collected at Port Arkansas, Texas in 1948 (Carlgren and Hedgepeth 1952) and subsequently found at Turkey Point, Florida (Minasian and Mariscal 1979) and Tampa Bay (Baker et al. 2004).
Diadumene lineata was first collected in Hawaii in 1972 by Daphne Fautin (Carlton and Eldredge 2015). Later, it was found in 1999 in Kaneohe Bay, Oahu on pilings among Pacific Oysters (Crassostrea gigas). Additional colonies were found in another location in Kaneohe Bay. Later, more anemones were found in 2000, on the remnants of a fishing net at at Pearl and Hermes Reef, Northwestern Hawaiian Islands (Zabin et al. 2004; Carlton and Eldredge 2009).
Diadumene lineata was first found in European waters at Millbay Docks, Plymouth, England in 1896 (Stephenson 1935). Other early records include occurrences on the Atlantic coast of France around 1900 (Goulletquer et al. 2002); Naples, Italy, in 1911 (USNM 42658, U.S. National Museum of Natural History 2007); Den Helder, Netherlands, in 1913 (Braber and Borghouts 1977; Wolff 2005); and the Lagoon of Venice in 1925 (Stephenson 1935). Populations appear to be scattered and subject to extinction and recolonization (Stephenson 1935). Known populations in the Atlantic extend through the Netherlands (Braber and Borghouts 1977; Wolff 1999), England (Stephenson 1935; Gollasch and Reimann-Zurneck 1996), and Ireland (Minchin 2007). A population was briefly established in German waters, near the mouth of the Elbe River, from 1920 to 1924, but may have been extinguished by fluctuating salinity (Gollasch and Reimann-Zurneck 1996). A single specimen was found in the Shetland Islands, Scotland, in 2003, but none have been found there since (Collin et al. 2015). In the Mediterranean, this anemone has been reported from harbors and lagoons in France and Italy, including those receiving commercial shipping like Naples (USNM 42658, U.S.National Museum of Natural History 2007) and Venice (Stephenson 1935). It has also been reported from smaller lagoons used for oyster culture, including Etang de Berre and Canet-St.Aigulf, France; and Etang de Biguglia, Corsica (Zibrowius 1991). It was found in the Black Sea, in Romania, beginning in 1960 (Bacescu et al. 1971, cited by Preda et al. 2012).
Outside of Europe, scattered populations of D. lineata are known from many parts of the world, including the Canary Islands (in 1994, Ocaña and den Hartog 2002); Malaysia and Singapore (in 1980, Dunn 1982; Fautin et al. 2009); New Zealand (in 1983, Cranfield et al. 1998); and Argentina (in 2005, Molina et al. 2008). Specimens in ship fouling, or other sporadic occurrences have been reported from Germany (in 1993, Gollasch and Reimann-Zurneck 1996); the Suez Canal (in 1924, Stephenson 1935); and Brazil (Farrapeira et al. 2011). A small colony was discovered in Chile in 2012 (Häussermann et al. 2015).
Most sea anemones of the genus Diadumene can reproduce sexually, by releasing eggs and sperm into the water, and asexually by longitudinal fission, or by a method called pedal laceration. In pedal laceration, as the anemone moves, a portion of its base is left behind and grows into a new anemone (Barnes 1983). However, in D. lineata, sexual reproduction has only been observed in Japan (Fukui 1991); while all of the introduced populations that have been studied, apparently reproduce only asexually (Stephenson 1935; Davis 1937; Minasian 1976). A population at Blue Hill Falls, Maine, occupying 2000 m2, consisted of a single all-male clone (Shick et al.1977). This population is the only one, outside Japan, known to reproduce by pedal laceration. Most populations consist of multiple clones, although one genotype often dominates (Ting and Geller 2000). In 2013, a population consisting both of males and females was found in Coos Bay, Oregon, although the occurrence and imporatnace of sexual reproduction has not yet been confirmed (Newcomer et al. 2019).
Diadumene lineata is known mostly from estuaries and sheltered waters, where it grows on oysters, rocks, seaweeds, roots of Spartina sp., pilings, and floats (Gosner 1978; Carlton 1979; Cohen and Carlton 1995; Casey 1999; Cohen 2005). This anemone is tolerant of variable salinity and temperature (Miyawaki 1951; Shick 1976). It can survive for two weeks in a contracted state at salinities of 2.5 to 5 PSU (Shick 1976), though the lower limit for feeding and prolonged survival is around 12 PSU (Miyawaki 1951). Diadumene lineata tolerated 4-hour exposures to 40°C (Sassaman and Mangum 1970), and no mortality at 1 to 27.5°C at 5-35 PSU (Shick 1976). It responds to low salinities and other stresses by contracting and secreting dense layers of mucus (Miyawaki 1951). Under some conditions of stress, it will form a cyst with a hard coating (Carlton 1979). However, because of the clonal nature of its populations, and low genetic diversity, a severe stress will often wipe out whole populations (Shick et al. 1979). Like other anemones, it feeds by trapping zooplankton and small epibenthic animals on its tentacles (Hausman 1919; Barnes 1983).
Zooplankton; small epibenthos
|General Habitat||Salt-brackish marsh|
|General Habitat||Grass Bed|
|General Habitat||Coarse Woody Debris|
|General Habitat||Oyster Reef|
|General Habitat||Marinas & Docks|
|General Habitat||Vessel Hull|
|Salinity Range||Polyhaline||18-30 PSU|
|Salinity Range||Euhaline||30-40 PSU|
|Salinity Range||Mesohaline||5-18 PSU|
|Tidal Range||Low Intertidal|
|Minimum Temperature (ºC)||0||Short-term field temperatures on intertidal rocks in Blue Hill Bay ME (Shick 1976).|
|Maximum Temperature (ºC)||40||Short-term field temperatures on intertidal rocks in Blue Hill Bay ME (Shick 1976).|
|Minimum Salinity (‰)||12||Exerimental- The minimum for volume regulation, feeding, and long-term survival was 12 PSU. However, <em>D. lineata</em> survives up to 2 weeks at 5 ppt in a contracted, mucus-covered state (Miyawaki 1951; Shick 1976). Podbielski et al. (2016) also found prolonged survival at at 7 PSU, but with greatly reduced feeding rates, and no asexual reproduction. At 14 PSU, asexual reproduction occurred, but at lower rates than at 24 and 32 PSU. <em>Diadumene lineata</em> has become established in the Kiel Bight, Baltic Sea, at 11-14 PSU (Podbielski et al. 2016).|
|Maximum Salinity (‰)||74||Experimental (Kiener 1971)|
|Broad Temperature Range||Cold temperate-Tropical|
|Broad Salinity Range||Mesohaline-Euhaline|