Invasion History

First Non-native North American Tidal Record: 1991
First Non-native West Coast Tidal Record: 1991
First Non-native East/Gulf Coast Tidal Record:

General Invasion History:

Symplegma reptans is a colonial tunicate, native to the Indo-West Pacific, where it occurs from northern Japan to Hong Kong (Nishikawa 1991; Huang 2001), Mumbai, India (Swami and Chhapgar 2002) and Queensland, Australia (Kott 1985). It has been introduced to Southern California, being first reported from Los Angeles Harbor in 1991.

North American Invasion History:

Invasion History on the West Coast:

Symplegma reptans was first collected in the northeast Pacific in 1991, in Los Angeles Harbor, and in San Diego Bay in 1994, but was initially misidentified as S. brakenhielmi. In 1997, it was found in Mission Bay, Dana Point Harbor, and Long Beach Harbor (Lambert and Lambert 1998; Lambert and Lambert 2003). In 1997-1998, this tunicate underwent a population explosion, creating dense single-species colonies (Lambert and Lambert 2003).

Invasion History in Hawaii:

In 1996, Symplegma reptans was found in Pearl Harbor in fouling on the floating drydock USS 'Machinist', which had been towed from the Philippines (Coles et al. 1999a; Coles et al. 1999b; Carlton and Eldredge, 2009). Its establishment in the Islands is uncertain.


Description

Symplegma reptans is a colonial tunicate with flattened zooids embedded within a thin, but tough, and nearly transparent tunic. Colonies grow in a flat mat which can be up to 2-3 mm thick, and 300+ mm diameter. Individual zooids are oblong in shape and randomly arranged within the common tunic. The color of the zooids varies from pink (Australia) or grayish to pinkish purple (Japan) with large triangular white patches, around the oral apertures. When the colonies are large and the zooids very densely packed, they form lobes and the pinkish color is much more noticeable. The zooids are usually arranged more randomly than in the photo (above). Each zooid has its own oral and atrial siphon that opens at the surface of the tunic. Both siphons are short, with frilled openings (Kott 1985; Nishikawa 1991; Gretchen Lambert 2012, personal communication).


Taxonomy

Taxonomic Tree

Kingdom:   Animalia
Phylum:   Chordata
Subphylum:   Tunicata
Class:   Ascidiacea
Order:   Stolidobranchia
Family:   Styelidae
Genus:   Symplegma
Species:   reptans

Synonyms

Synstyela reptans (Oka, 1927)

Potentially Misidentified Species

Symplegma brakenhielmi
None

Symplegma rubra
None

Symplegma viride
None

Ecology

General:

A colonial (or compound) tunicate consists of many zooids, bearing most or all of the organs of a solitary tunicate, but modified to varying degrees for colonial life. Colonial ascidians of the genera Symplegma have small, flattened, ovate zooids, but these are not arranged in systems. The zooids are embedded in a mass of tunic material. Each zooid has an oral and atrial siphon. Water is pumped into the oral siphon, through finely meshed ciliated gills on the pharynx, where phytoplankton and detritus is filtered, and passed on mucus strings to the stomach and intestines. Excess waste is expelled in the outgoing atrial water (Van Name 1945; Barnes 1983).

Colonial ascidians reproduce both asexually, by budding, and sexually, from fertilized eggs developing into larvae. Buds can form from the body wall of the zooid. Colonies vary in size, and can range from small clusters of zooids to huge spreading masses. The zooids are hermaphroditic, with eggs and sperm being released to the atrial chamber. Eggs may be self-fertilized or fertilized by sperm from nearby animals, but some species have a partial block to self-fertilization. Eggs are brooded in the atrial chamber, and hatch into tadpole larvae, with a muscular tail and a notochord, eyespots, and a set of adhesive papillae. The lecithotrophic (non-feeding, yolk-dependent) larvae are expelled on hatching, and swim briefly before settlement. Swimming periods are usually less than a day, and some larvae can settle immediately after release, but the larval period can be longer at lower temperatures. On settlement, the tail is absorbed, the gill basket expands, and the tunicate begins to feed by filtering (Van Name 1945; Barnes 1983).

Food:

Phytoplankton, detritus

Trophic Status:

Suspension Feeder

SusFed

Habitats

General HabitatMarinas & DocksNone
General HabitatVessel HullNone
General HabitatRockyNone
Salinity RangePolyhaline18-30 PSU
Salinity RangeEuhaline30-40 PSU
Tidal RangeSubtidalNone
Vertical HabitatEpibenthicNone


Tolerances and Life History Parameters

Broad Temperature RangeNoneWarm temperate-Tropical
Broad Salinity RangeNonePolyhaline-Euhaline

General Impacts

Ecological Impacts-

Competition- Symplegma reptans created extensive areas of 100% cover at sites in San Diego and Mission Bays in 1998, suggestive of competition (Lambert and Lambert 2003).

Regional Impacts

P020San Diego BayEcological ImpactCompetition
Symplegma reptans created extensive areas of 100% cover at sites in San Diego and Mission Bays in 1998, suggestive of competition (Lambert and Lambert 2003).
P030Mission BayEcological ImpactCompetition
Symplegma reptans created extensive areas of 100% cover at sites in San Diego and Mission Bays in 1998, suggestive of competition (Lambert and Lambert 2003).
NEP-VIPt. Conception to Southern Baja CaliforniaEcological ImpactCompetition
Symplegma reptans created extensive areas of 100% cover at sites in San Diego and Mission Bays in 1998, suggestive of competition (Lambert and Lambert 2003).
CACaliforniaEcological ImpactCompetition

Symplegma reptans created extensive areas of 100% cover at sites in San Diego and Mission Bays in 1998, suggestive of competition (Lambert and Lambert 2003).

Regional Distribution Map

Bioregion Region Name Year Invasion Status Population Status
P030 Mission Bay 1997 Def Estab
P027 _CDA_P027 (Aliso-San Onofre) 1997 Def Estab
NEP-VI Pt. Conception to Southern Baja California 1995 Def Estab
P020 San Diego Bay 1995 Def Estab
P050 San Pedro Bay 1991 Def Estab

Occurrence Map

OCC_ID Author Year Date Locality Status Latitude Longitude
697763 ISS 2000-2002 Survey Data 2001 2001-10-09 San Diego Bay Commercial Fishing Fleet Def 32.7109 -117.1739
698680 ISS 2000-2002 Survey Data 2001 2001-10-09 Marine Terminal (Paco) Def 32.6584 -117.1191
698681 Introduced Species Study 2011 2011-05-03 Marine Terminal (Paco) Def 32.6584 -117.1191
698682 Maloney et al. 2007 2005 2005-04-27 Marine Terminal (Paco) Def 32.6584 -117.1191
698965 Introduced Species Study 2011 2011-05-04 Dana Inn Marina Def 32.7671 -117.2362
699804 Maloney et al. 2007 2005 2005-04-27 Coronado Wharf Def 32.6992 -117.1684
699807 ISS 2000-2002 Survey Data 2001 2001-10-09 Coronado Wharf Def 32.6992 -117.1684
700614 MEC Analytical Systems, Inc. et al. 2002 (Los Angeles/Long Beach Baseline Study of 2000) 2000 Los Angeles/Long Beach Harbor Complex Def 33.7632 -118.2526
700644 Introduced Species Study 2006 2006-09-12 Santa Barbara Cove Def 32.7774 -117.2484
702473 Lambert and Lambert 2003 1994 San Diego Bay Def 32.6717 -117.1439
702548 Lambert and Lambert 2003 1991 Los Angeles Harbor Def 33.7269 -118.2623
702745 Cohen et al. 2002 (So Cal Exotics RAS) 2000 2000-08-24 Cabrillo Beach Boat Ramp Def 33.7134 -118.2839
702870 Cohen et al. 2002 (So Cal Exotics RAS); Lambert and Lambert 2003 2000 2000-08-26 Fiddler's Cove Def 32.6519 -117.1494
703068 Introduced Species Study 2011 2011-05-03 San Diego Bay Cruise Ship Terminal Def 32.7168 -117.1759
703107 Maloney et al. 2007 2005 2005-04-26 Switzer Creek Def 32.7043 -117.1615
703198 Maloney et al. 2007 2005 2005-06-28 Ballast Point Def 32.6861 -117.2348
703525 Cohen et al. 2002 (So Cal Exotics RAS); Lambert and Lambert 2003 2000 2000-08-26 Shelter Island Def 32.7100 -117.2342
704647 Maloney et al. 2007 2005 2005-06-28 Navy - Carrier Base Def 32.7062 -117.1886
757668 Lambert and Lambert 1998; Lambert and Lambert 2003 1997 1997-04-05 Impound Marina, Long Beach Def 33.7639 -118.2444
757669 Lambert and Lambert 2003 1997 Impound Marina, Long Beach Def 33.7639 -118.2444
757670 Lambert and Lambert 2003 1998 Impound Marina, Long Beach Def 33.7639 -118.2444
757671 Lambert and Lambert 2003 1997 Dana Point Harbor Def 33.4598 -117.6956
757672 Lambert and Lambert 2003 1998 Dana Point Harbor Def 33.4598 -117.6956
757673 Lambert and Lambert 2003 1997 Santa Clara Point Boat Launch, Mission Bay Def 32.7824 -117.2499
757674 Lambert and Lambert 2003 1998 Santa Clara Point Boat Launch, Mission Bay Def 32.7824 -117.2499
757675 Lambert and Lambert 1998; Lambert and Lambert 2003 1997 1997-04-06 Mission Bay Yacht Club Def 32.7790 -117.2469
757676 Lambert and Lambert 2003 1997 Mission Bay Yacht Club Def 32.7790 -117.2469
757677 Lambert and Lambert 2003 1998 Mission Bay Yacht Club Def 32.7790 -117.2469
757678 Lambert and Lambert 1998; Lambert and Lambert 2003 1997 1997-04-06 Bahia Point, Mission Bay Def 32.7761 -117.2468
757679 Lambert and Lambert 2003 1997 Bahia Point, Mission Bay Def 32.7761 -117.2468
757680 Lambert and Lambert 2003 1998 Bahia Point, Mission Bay Def 32.7761 -117.2468
757681 Lambert and Lambert 1998; Lambert and Lambert 2003 1997 1997-04-06 South Shores Boat Ramp, Mission Bay Def 32.7644 -117.2168
757682 Lambert and Lambert 2003 1997 South Shores Boat Ramp, Mission Bay Def 32.7644 -117.2168
757683 Lambert and Lambert 2003 1998 Dana Landing, Mission Bay Def 32.7674 -117.2357
757684 Lambert and Lambert 2003 1997 Seaforth Landing Def 32.7644 -117.2381
757685 Lambert and Lambert 2003 1998 Seaforth Landing Def 32.7644 -117.2381
757686 Lambert and Lambert 1998; Lambert and Lambert 2003 1995 1995-03-26 Fiddler's Cove, San Diego Bay Def 32.6519 -117.2342
757687 Lambert and Lambert 2003 1997 Fiddler's Cove, San Diego Bay Def 32.6519 -117.2342
757688 Lambert and Lambert 2003 1998 Fiddler's Cove, San Diego Bay Def 32.6519 -117.2342
757689 Lambert and Lambert 1998; Lambert and Lambert 2003 1994 1994-10-09 24th Street Boat Launch, San Diego Bay Def 32.6495 -117.1108
757690 de Rivera et al. 2005a 2003 Dana Marina Def 32.7675 -117.2365
767429 Ruiz et al., 2015 2013 2013-07-19 SeaWorld Marina, Mission Bay, CA, California, USA Def 32.7676 -117.2314
767465 Ruiz et al., 2015 2013 2013-07-29 Mission Bay Yacht Club, Mission Bay, CA, California, USA Def 32.7778 -117.2485
767485 Ruiz et al., 2015 2013 2013-08-04 Bahia Resort Marina, Mission Bay, CA, California, USA Def 32.7731 -117.2478
767532 Ruiz et al., 2015 2013 2013-08-03 Mission Bay Sport Center, Mission Bay, CA, California, USA Def 32.7857 -117.2495
767559 Ruiz et al., 2015 2013 2013-08-02 The Dana Marina, Mission Bay, CA, California, USA Def 32.7671 -117.2363
767571 Ruiz et al., 2015 2013 2013-08-05 Paradise Point Resort, Mission Bay, CA, California, USA Def 32.7730 -117.2406
767686 Ruiz et al., 2015 2013 2013-07-17 Naval Station San Diego, San Diego Bay, CA, California, USA Def 32.6867 -117.1333
767712 Ruiz et al., 2015 2013 2013-07-25 Navy Ammo Dock, Pier Bravo, San Diego Bay, CA, California, USA Def 32.6939 -117.2276
767723 Ruiz et al., 2015 2013 2013-07-21 Cabrillo Isle Marina, San Diego Bay, CA, California, USA Def 32.7272 -117.1995
767753 Ruiz et al., 2015 2013 2013-07-18 NAB Fiddlers Cove, San Diego Bay, CA, California, USA Def 32.6524 -117.1486
769443 Ruiz et al., 2021b 2018 2018-08-10 Alamitos Bay Marina, San Pedro Bay, California, USA Def 33.7494 -118.1154

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