Invasion History

First Non-native North American Tidal Record: 1859
First Non-native West Coast Tidal Record: 1859
First Non-native East/Gulf Coast Tidal Record:

General Invasion History:

Ectopleura crocea (also known as Pinauay crocea or Tubularia crocea) was first described from 'Boston Bay', Massachusetts by Louis Agassiz in 1862 (as Parypha crocea). On the Atlantic coast of North America, its presumed native region, E. crocea has been collected from the Miramichi Estuary, New Brunswick, south to Lake Worth, Florida and Port Aransas, Texas (Fraser 1944; Deevey 1950; Defenbaugh 1973; Ruiz et al. unpublished data). It has also been collected on the Caribbean shore of South America at Santa Marta, Colombia (Wedler 1975), where we consider it cryptogenic. Ectopleura crocea has a wide global distribution and was apparently introduced to non-native locations starting in or before the 19th century (Deevey 1950; Carlton 1979; Watson 1999).

North American Invasion History:

Invasion History on the West Coast:

Even before its description in Massachusetts, this hydroid was collected from San Francisco Bay, California (as Parypha microcephala, Agassiz 1859, cited by Carlton 1979). In San Francisco Bay, it occurs in the Central Bay, the South Bay, and San Pablo Bay (Carlton 1979; Cohen and Carlton 1995; Cohen et al. 2005; Ruiz et al. unpublished data).To the south, E. crocea was collected from the major ports of San Diego (in 1876, Clark 1876, cited by Carlton 1979) and Los Angeles (in 1902, Torrey 1902, cited by Carlton 1979), before it was recorded from the smaller coastal bays: Mission Bay (in 1896, USNM 43547, U.S. Museum of Natural History 2007), Newport Bay (in 1938, Carlton 1979, USNM 43543, U.S. Museum of Natural History 2007), Kings Harbor, Santa Monica Bay (Fraser 1948, cited by Carlton 1979), and Elkhorn Slough (MacGinitie 1935, cited by Carlton 1979, Wasson et al. 2001).

To the north, E. crocea was reported from Port Simpson, British Columbia (54.6 N) in 1911. Early collections were also made from the San Juan Islands (Washington), north to the Queen Charlotte Islands, and an unspecified record from 'the Gulf of Alaska' (Fraser 1937; Carlton 1979). Mills (in Cohen et al. 1998) considered the reports from San Juan Islands to be unverified, and perhaps the result of taxonomic confusion. However, this hydroid was found on fouling plates in Ketchikan, Alaska, in 2003 (Ruiz et al. 2006). We do not know if this hydroid is established in Alaska or British Columbia. Ectopleura crocea was collected in Coos Bay, Oregon starting in 1948 (Fraser 1948, cited by Carlton 1979; Carlton 1989; Ruiz et al., unpublished data), and on fouling plates in Humboldt Bay, California in 2003 (Ruiz et al., unpublished data).

Invasion History Elsewhere in the World:

Ectopleura crocea has been reported from the tropical Pacific at Jicaron Island, Panama (Fraser 1938), from fouling plates in Salinas, Ecuador (2018, Calder et al. 2021), and the southeastern Pacific at Valparaiso, Chile (1905, Deevey 1950). In the southwestern Pacific, it was first collected in Victoria, Australia, in Port Phillip Bay (as Tubularia ralphii, Bale 1884, cited by Watson 1999). It has also been collected in Sydney Harbor and Port Kembla, in New South Wales, at Fremantle, in Western Australia (Watson 1999), at Auckland, New Zealand (Cranfield et al. 1998). In the northeast Atlantic, E. crocea appears to be an introduction. It was first collected in the Azores in 1989 (Cardigos et al. 2006) and is also known from Madeira (Wirtz 2007). It was noted as a rare occurrence on ship hulls at Plymouth, England in 1895 and 1907 (Plymouth Marine Fauna, and at Ipswich, England in 1959 (Rees 1963). It is not listed as a Mediterranean invader by Galil (2009), but available references suggest that it is mostly known from harbors (e.g., Villefranche-sur-mer, France, 1895, Schuchert 2010; Bay of Naples, Italy, 1892, Bouillon et al. 2004; Israel 1946, Vervoort 1993). In the southwest Atlantic, it occurs from Uruguay to Bahia Blanca, Argentina (Genzano et al. 2005). It was first reported from this region in 1971 and is considered cryptogenic there (Orensanz et al. 2003). In South Africa, it was found in Durban and Cape Town in 1947 (Ewer 1953, cited by Millard 1975, as Tubularia warreni; Schuchert 2010; (1947, Millard 1952, cited by Mead et al. 2011). In the Northwest Pacific, Tubularia sagaminea and T. mesembryanthemum, reported from Japan (Stechow 1907; Yamada 1959; Hirohito 1988) and China (Hargitt 1927, Yamada 1959. all cited by Imazu et al. 2014), are all considered synonyms of E. crocea.


Ectopleura crocea, also commonly known as Pinauay or Tubularia crocea, is a hydrozoan which lacks a medusa stage. Its colonies grow from branching stolons, in tangled masses up to 100–120 mm in height, and consist of up to several hundred unbranched stems, with one hydranth per stalk. The perisarc is wrinkled with a few annulations, but there are no joints in the stalk. The hydranth is vase-shaped with a long hypostome. The tentacles are threadlike, in two whorls of 20–24 each. The proximal-whorl tentacles are larger and longer than those in the distal whorl. The female gonophores are carried on 12–16 blastostyles, hanging below the tentacles. The female gonophores produce eggs, which develop into planktonic actinula larvae resembling miniature hydranths, usually with four tentacles. Production of these larvae may vary regionally; being rare (West Coast, Fraser 1937) or frequent (Chesapeake Bay, Calder 1971). The male gonophores are oval or spherical, without apical processes. The body of the hydranth is pink (description from: Fraser 1937; Calder 1971; Watson 1999; Schuchert 2010).

The correct genus name for this hydroid is disputed. Marques and Migotto (2000) published a cladistic analysis of the genus Ectopleura which supported the monophyly of the genus, but found that genus consisted of two subclades, and put several widespread species including E. larynxE. crocea, and E. marina into a new genus, Pinauay. Schuchert (2010) considers the split to be unjustified. Imazu et al. (2014) review the taxonomy and distribution of this hydroid, using the name E. crocea. They tentatively support the synonymy of Western Atlantic E. crocea with E. ralphi, as described from Australia and based on Brazilian specimens, but suggest that worldwide morphological and genetic comparisons are needed.


Taxonomic Tree

Kingdom:   Animalia
Phylum:   Cnidaria
Class:   Hydrozoa
Subclass:   Hydroidolina
Order:   Anthoathecatae
Suborder:   Filifera
Family:   Tubulariidae
Genus:   Ectopleura
Species:   crocea


Parypha microcephala (L. Agassiz, 1859)
Paryphya crocea (L. Agassiz, 1862)
Pinauay crocea (Marques and Migotto, 2000)
Tubularia crocea (Allman, 1872)
Tubularia mesembryanthemum (Allman, 1871)
Tubularia polycarpa (Allman, 1872)
Tubularia ralphi (Bale, 1884)
Tubularia gracilis (von Lendenfeld, 1885)
Tubularia australis (Stechow, 1924)
Tubularia warreni (Ewer, 1953)
Tubularia sagamina (Stechow, 1907)
Ectopleura media (Fraser, 1938)

Potentially Misidentified Species

Ectopleura integra
Native to the Galapgos, releases medusae (Calder et al. 2019)

Ectopleura marina
West Coast on open shores (Mills et al., in Carlton 2007)



The hydroid Ectopleura crocea lacks a free-living medusa. It does have a short-lived (~24 hours) planktonic lecithotrophic larval form, known as an actinula, resembling a small sea-anemone. It grows on a solid substrate, with polyps arising from branching, creeping stolons. The polyps grow as single stalks, each bearing a hydranth, whose tentacles capture zooplankton. The polyps produce bunches of gonophores, which produce either eggs or sperm. Colonies are diecious (single-sexed). Female gonophores produce multiple eggs, typically 2–4, which are brooded and fertilized by sperm in the water column. The egg develops in the gonophore through the planula stage into an actinula (Barnes 1983; Bouillon et al. 2004; Schuchert 2010). Larvae spend about 24 hours in the water column (as Ectopleura mesembryanthemum; Yamashita et al. 2003).

This hydroid occurs on a variety of substrates, including rocks, shells, concrete, pilings, buoys, jetties, pipes, and ships’ hulls (Fraser 1944; Woods Hole Oceanographic Institution 1952; Calder 1971; Gosner 1978). It is characteristic of harbors and polluted waters (Bouillon et al. 2004; Schuchert 2010). In South Carolina, it was found at a salinity range of 23–34 PSU (Calder 1976). The occurrences of Ectopleura crocea in Salinas, Ecuador, with mean water temperature of 24 °C, increases the known temperature tolerance of this hydroid (Calder et al. 2021).


Zooplankton, small epibenthos




Trophic Status:




General HabitatOyster ReefNone
General HabitatCoarse Woody DebrisNone
General HabitatMarinas & DocksNone
General HabitatRockyNone
General HabitatVessel HullNone
Salinity RangePolyhaline18-30 PSU
Salinity RangeEuhaline30-40 PSU
Tidal RangeSubtidalNone
Vertical HabitatEpibenthicNone

Life History

Tolerances and Life History Parameters

Minimum Temperature (ºC)0Based on geographical range
Maximum Temperature (ºC)30Charleston Harbor SC (Calder 1992)
Minimum Salinity (‰)23Field distribution, SC (Calder1976)
Maximum Salinity (‰)34Field distribution, SC (Calder1976)
Maximum Duration1Yamashita et al. 2003, for Ectopleura mesembryanthemum
Broad Temperature RangeNoneCold temperate-Tropical
Broad Salinity RangeNonePolyhaline-Euhaline

General Impacts

Ectopleura crocea is frequently an abundant fouling organism in its native and introduced ranges. It seems to prefer man-made structures and is tolerant of polluted waters (Schuchert 2010). It is also occurs on mussel shells and around mussel beds, and is a potential competitor with mussels and a possible predator on their larvae (Okamura 1986; Fitridge 2011).

Economic impacts

Ectopleura crocea has been reported from pilings, buoys, jetties, pipes, and ship hulls (Fraser 1944; Woods Hole Oceanographic Institution 1952; Calder 1971; Gosner 1978). It is probably an important contributor to fouling communities because of its size and frequent abundance. However, specific impacts on shipping have not been reported.

Fisheries- Ectopleura crocea fouls cultured mussels (Mytilus galloprovincialis) in Port Phillip Bay, Australia, with adverse effects on their growth and condition, possibly due to competition for food, and on the recruitment of larvae due to predation (Fitridge 2011).

Ecological Impacts

Competition-Ectopleura crocea was a dominant form on fouling plates in San Francisco Bay (Okamura 1986).

Habitat Change- The degenerating stalks of Ectopleura crocea provided a filamentous surface for metamorphosing larvae of Mytilus spp. on fouling plates in San Francisco Bay (Okamura 1986), and in Port Phillip Bay, Australia (Fitridge 2011).

Impacts in the Galapagos Islands

Impacts are unknown in the Galapagos Islands.

Regional Impacts

NEP-VNorthern California to Mid Channel IslandsEcological ImpactCompetition
Ectopleura crocea was a dominant form on fouling plates in San Francisco Bay in late summer and fall, occupying up to 60% of the plates' surface, reaching a peak in October (Okamura 1986).
NEP-VNorthern California to Mid Channel IslandsEcological ImpactHabitat Change
The degenerating stalks of Ectopleura crocea provided a filamentous surface for metamorphosing larvae of Mytilus spp. on fouling plates in San Francisco Bay in winter, facilitating the establishment of dense populations in spring (Okamura 1986).
P090San Francisco BayEcological ImpactCompetition
Ectopleura crocea was a dominant form on fouling plates in San Francisco Bay in late summer and fall, occupying up to 60% of the plates' surface, reaching a peak in October (Okamura 1986).
P090San Francisco BayEcological ImpactHabitat Change
The degenerating stalks of Ectopleura crocea provided a filamentous surface for metamorphosing larvae of Mytilus spp. on fouling plates in San Francisco Bay in winter, facilitating the establishment of dense populations in spring (Okamura 1986).
AUS-VIIINoneEconomic ImpactFisheries
Fisheries- Ectopleura crocea was fouling cultured mussels (Mytilus galloprovincialis) in Port Phillip Bay, Australia, reducing their condition index, particularly for younger mussels. Competition for food may be affecting mussel growth. The hydroid's predation on larval mussels, especially settling larvae, may be reducing recruitment. However, the stalks of the hydroids, especially when degenerating, provide a surface for the settlement of mussel larvae (Fitridge 2011; Fitridge and Keough 2013).
CACaliforniaEcological ImpactCompetition
Ectopleura crocea was a dominant form on fouling plates in San Francisco Bay in late summer and fall, occupying up to 60% of the plates' surface, reaching a peak in October (Okamura 1986)., Ectopleura crocea was a dominant form on fouling plates in San Francisco Bay in late summer and fall, occupying up to 60% of the plates' surface, reaching a peak in October (Okamura 1986).
CACaliforniaEcological ImpactHabitat Change
The degenerating stalks of Ectopleura crocea provided a filamentous surface for metamorphosing larvae of Mytilus spp. on fouling plates in San Francisco Bay in winter, facilitating the establishment of dense populations in spring (Okamura 1986)., The degenerating stalks of Ectopleura crocea provided a filamentous surface for metamorphosing larvae of Mytilus spp. on fouling plates in San Francisco Bay in winter, facilitating the establishment of dense populations in spring (Okamura 1986).

Regional Distribution Map

Bioregion Region Name Year Invasion Status Population Status
NA-ET3 Cape Cod to Cape Hatteras 0 Native Estab
NA-ET2 Bay of Fundy to Cape Cod 0 Native Estab
CAR-VII Cape Hatteras to Mid-East Florida 0 Native Estab
NA-ET1 Gulf of St. Lawrence to Bay of Fundy 0 Native Estab
NA-S3 None 0 Native Estab
CAR-I Northern Yucatan, Gulf of Mexico, Florida Straits, to Middle Eastern Florida 0 Native Estab
NEP-VI Pt. Conception to Southern Baja California 1876 Def Estab
NEP-V Northern California to Mid Channel Islands 1859 Def Estab
NEP-IV Puget Sound to Northern California 1948 Def Estab
SA-II None 1966 Crypto Estab
SEP-B None 1905 Def Unk
MED-V None 1946 Def Estab
MED-VII None 1988 Def Estab
AUS-VIII None 1884 Def Estab
AUS-IV None 1998 Def Estab
AUS-X None 1885 Def Estab
NZ-IV None 1994 Def Estab
NEA-IV None 1910 Def Estab
NEA-III None 1907 Def Unk
MED-II None 1871 Def Estab
MED-III None 1892 Def Estab
NEA-VI None 1989 Def Estab
NEP-III Alaskan panhandle to N. of Puget Sound 1911 Def Estab
NEP-II Alaska south of the Aleutians to the Alaskan panhandle 1937 Def Unk
P020 San Diego Bay 1876 Def Estab
P050 San Pedro Bay 1902 Def Estab
P170 Coos Bay 1948 Def Estab
P090 San Francisco Bay 1859 Def Estab
P040 Newport Bay 1938 Def Estab
P060 Santa Monica Bay 1948 Def Estab
P080 Monterey Bay 1935 Def Estab
P030 Mission Bay 1896 Def Estab
CAR-III None 0 Crypto Estab
NEA-II None 1959 Def Unk
SEP-H None 1934 Def Unk
P093 _CDA_P093 (San Pablo Bay) 1865 Def Estab
P130 Humboldt Bay 2003 Def Estab
WA-I None 1995 Def Estab
SA-I None 0 Crypto Estab
RS-3 None 1951 Def Estab
WA-IV None 1947 Def Estab
WA-V None 1953 Def Estab
P292 _CDA_P292 (San Juan Islands) 1932 Def Unk
P070 Morro Bay 1986 Def Estab
NWP-3b None 1907 Def Estab
NWP-2 None 1927 Def Estab
NWP-3a None 1959 Def Estab
MED-VI None 1972 Def Estab
PAN_PAC Panama Pacific Coast 1934 Def Unk
SA-III None 2008 Crypto Estab
AUS-IX None 1952 Def Estab
AUS-XII None 1955 Def Estab
AUS-XI None 2003 Def Estab
SEP-I None 2018 Def Estab
SEP-H None 1934 Def Estab
SEP-I None 2018 Def Estab
SEP-Z None 1934 Def Estab

Occurrence Map

OCC_ID Author Year Date Locality Status Latitude Longitude
2924 Ruiz et al., unpublished data (DOD) 2003 2003-01-01 Cabrillo Isle Marina, San Diego Def 32.7265 -117.2009
2928 Carlton 1979, citing MacGinitie 1939 1939 1939-01-01 Newport Bay Def 33.6083 -117.9083
2929 Carlton 1979, citing Riesh 1972 1972 1972-01-01 Long beach Def 33.7497 -118.1172
2931 Carlton 1979, citing Campbell 1922 1922 1922-01-01 Long Beach Def 33.7669 -118.1883
2932 Carlton 1979, citing Fraser 1948 1948 1948-01-01 Redondo Beach Def 33.9350 -118.4658
2933 Carlton 1979, citing MacGinitie 1935 1935 1935-01-01 Elkhorn Slough Def 36.8058 -121.7902
2934 Carlton 1979, citing Agassiz 1865 1865 1865-01-01 San Francisco Bay Def 37.7083 -122.2792
2947 Ruiz et al., unpublished data (DOD) 2000 2000-09-01 Dumbarton Swing (Railway) Bridge Def 37.5003 -122.1168
2952 Carlton 1979, citing Fraser 1948 1948 1948-01-01 Coos Bay Def 43.3988 -124.2222
2953 Ruiz et al., unpublished data (DOD) 2000 2000-09-01 None Def 43.3772 -124.2964
2954 Ruiz et al., unpublished data (DOD) 2000 2000-09-01 Coos Bay City Dock, Coos Bay Def 43.3674 -124.2118
2955 Ruiz et al., unpublished data (DOD) 2000 2000-09-01 ICW Dock, Coos Bay Def 43.4009 -124.2828
2956 Ruiz et al., unpublished data (DOD) 2000 2000-09-01 Citrus,Army corps, and Central Docks, Coos Bay Def 43.3799 -124.2160
2960 Ruiz et al., unpublished data (DOD) 2000 2000-09-01 Jarvis Range Markers, Coos Bay Def 43.4172 -124.2767
2964 Ruiz et al., unpublished data (DOD) 2000 2000-09-01 Romberg Tiburon Center, Tiburon Def 37.8909 -122.4463
2972 Ruiz et al., unpublished data (DOD) 2000 9999-01-01 Port of San Francisco Pier 23 Def 37.8045 -122.3985
6076 US National Museum of Natural History 2009 1878 1878-07-23 Off Thatcher's Island Light And Eastern Point Native 42.5807 -70.6642
6077 US National Museum of Natural History 2009 1884 1884-08-25 Off Menemsha, Martha's Vineyard Native 41.3529 -70.7786
6078 US National Museum of Natural History 2009 1872 1872-01-01 None Native 45.0000 -66.0000
6079 US National Museum of Natural History 2009 1877 1877-01-01 Halifax Native 44.6501 -63.5993
6080 US National Museum of Natural History None 9999-01-01 Off Noank Native 41.3279 -71.9906
6081 US National Museum of Natural History 2009 1911 1911-08-01 None Native 43.6334 -70.0495
6082 US National Museum of Natural History 2009 1891 1891-02-12 Port Royal, Naval Station Def 32.3791 -80.6926
6083 US National Museum of Natural History 2009) 1938 1938-03-01 Lake Worth, Native 26.6159 -80.0570
6084 Ruiz et al., unpublished data 2003 2003-09-01 Humboldt Bay Def 40.7499 -124.2095
6085 Fraser 1944 1944 1944-01-01 None Native 47.1167 -65.1667
6086 Deevey 1950 1947 1947-03-20 Port Aransas Native 27.8339 -97.0611
6087 Calder 1971 1971 1971-01-01 Chesapeake Bay Bridge Tunnel Native 37.0335 -76.0830
6088 Defenbaugh 1973 1973 1973-01-01 Seaside Beach, Galveston Native 29.2758 -94.8774
6089 Defenbaugh 1973 1968 1968-01-01 Panama City Native 30.1588 -85.6602
6090 Prezant et al. 2005 None 9999-01-01 Main Dock, St. Catherines Island Native 31.6569 -81.1515
6091 Hidu 1978 1966 1966-08-30 Cape May Native 38.9593 -74.9274
6092 Dean and Hurd 1980 1975 1975-11-01 University of Delaware Marine Station, Lewes Native 38.7848 -75.1607
6093 Pearse 1928 1928 1928-01-01 Pivers Island, Beaufort Native 34.7177 -76.6722
6094 US National Museum of Natural History 2009 1935 1935-01-29 Charleston Native 32.7638 -79.8973
6097 Wedler 1975 1975 1975-01-01 Santa Marta Crypto 11.2500 -74.2167
767666 Ruiz et al., 2015 2013 2013-07-16 Naval Base Point Loma, San Diego Bay, CA, California, USA Def 32.6886 -117.2343
768035 Ruiz et al., 2015 2012 2012-08-27 Port of San Francisco Pier 31, San Francisco Bay, CA, California, USA Def 37.8078 -122.4060
768168 Ruiz et al., 2015 2012 2012-09-05 Port of Oakland, San Francisco Bay, CA, California, USA Def 37.7987 -122.3228


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