Invasion History

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

General Invasion History:


North American Invasion History:




Taxonomic Tree

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


Ectopleura pacifica (Thornley, 1900)

Potentially Misidentified Species

Ectopleura indica
Reported from India as E. pacifica (Mammen 1963, cited by Schuchert 2003)



Ectopleura viridis has both a sessile hydroid stage and a free-swimming medusa stage (Mayer 1910; Schuchert 2003). The appears to have an affinity for man-made structures, occurring on floats and fish traps in New Britain (Mayer 1910) and on mooring buoys in Apra Harbor (Kirkendale and Calder 2003), but it is also known from corals, sponges, and crabs (Schuchert 2003).


Zooplankton, epibenthos

Trophic Status:

Suspension Feeder



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

Tolerances and Life History Parameters

Broad Temperature RangeNoneTropical
Broad Salinity RangeNonePolyhaline-Euhaline

General Impacts

Regional Distribution Map

Bioregion Region Name Year Invasion Status Population Status
SP-II None 0 Native Estab
EAS-III None 1890 Native Estab
SP-I None 0 Native Estab
SP-XX None 0 Native Estab
CIO-VI None 0 Native Estab
SP-XII None 2000 Def Estab
SP-XXI None 1978 Def Unk

Occurrence Map

OCC_ID Author Year Date Locality Status Latitude Longitude


Calder, Dale R. (2010) Some anthoathecate hydroids and limnopolyps (Cnidaria, Hydrozoa) from the Hawaiian archipelago, Zootaxa 2590: 1-91

Kirkendale, Lisa; Calder, Dale R. (2003) Hydroids (Cnidaria: Hydrozoa) from Guam and the Commonwealth of the Northern Marianas Islands (CNMI), Micronesica 35-36: 159-188

Mayer, A. G. (1910) Medusae of the World., In: (Eds.) . , Washington, D.C.. Pp. 231, 276-278

Paulay, Gustav; Kirkendale, Lisa; Lambert, Gretchen; Meyer, Chris (2002) Anthropogenic biotic interchange in a coral reef ecosystem: a case study from Guam, Pacific Science 56(2): 403-422

Schuchert, Peter (2003) Hydroids (Cnidaria, Hydrozoa) of the Danish expedition to the Kei Islands, Steenstrupia 27(2): 137-256.