Invasion History

First Non-native North American Tidal Record: 1875
First Non-native West Coast Tidal Record: 1948
First Non-native East/Gulf Coast Tidal Record: 1875

General Invasion History:

Chelura terebrans is a wood-boring amphipod first described by Philippi from Trieste, Italy in 1839, and redescribed by Allman (1847) from Ireland. Its native range is uncertain, as it has a wide global distribution being found from 18°N – 61°N in the northern hemisphere and 30ºS – 44ºS in the southern hemisphere. In the Eastern Atlantic, it ranges from Norway to Spain, and through the Mediterranean and Black Seas (Kuhne and Becker 1964). Chelura terebrans has been reported from the Northwestern Atlantic (Maine to Long Island; Wallour 1960), South Africa (Mead 2011b), the Northeastern Pacific (Washington to California; Wallour 1960; Carlton 1979), Australia and New Zealand (Kuhne and Becker 1964). It was likely transported to many locations in the hulls of wooden ships (Kuhne and Becker 1964). Chelura terebrans usually co-occurs with the wood-boring isopods of the genus Limnoria (Barnard 1955; Kuhne and Becker 1964) and is largely dependent on these borers for shelter and food, due to Limnoria's superior wood-eating ability.

North American Invasion History:

Invasion History on the West Coast:

Chelura terebrans was first collected in 1948 at the Hunters Point Naval Shipyard in San Francisco Bay, California (Cohen and Carlton 1995). It was subsequently found in several locations in the central bay, at Sausalito in 1949 (Barnard 1950); Tiburon in 1949 (Barnard 1950); and Lake Merritt, in Oakland (Carlton 1979). In 1950, C. terebrans was found at Cabrillo Beach, Los Angeles, San Pedro Bay, and in sample blocks placed in Los Angeles-Long Beach Harbors (Barnard 1950). It was also found in Long Beach Harbor in a survey in 2000 (Cohen et al. 2002). North of San Francisco Bay, C. terebrans was found in Humboldt Bay, California in 2000 (Boyd et al. 2002) and Grays Harbor, Washington (Wallour 1960, Carlton 1979).

Invasion History on the East Coast:

Chelura terebrans was first found at Woods Hole, Massachusetts (MA) in 1875 by Smith (1879): 'I have repeatedly made careful search of Chelura at many different points along our eastern coast from New Jersey to Nova Scotia, and have examined many pieces of Teredo and Limnoria-bored timber from other parts of the coast, but until 1875, I was not able to discover an individual of the genus.' (Smith 1879). Chelura terebrans was abundant at Provincetown, MA in 1879 (Smith 1879) and also found at Portland Harbor, Maine (ME), Boston Harbor, MA in 1951-52 (Brown 1953; Wallour 1960) and earlier (Atwood 1935, cited by Kuhne and Becker 1964). The southern limits are less clear. Chelura terebrans was collected in Long Island Sound around 1935 (Atwood 1935, cited by Kuhne and Becker 1964; Brown 1953; Wallour 1960). Bousfield (1973) gives the range of C. terebrans as 'south to Chesapeake Bay and northern Florida'. However, no specific records were given in the Clapp Laboratory's wood-borer surveys (Brown 1953; Wallour 1960), museum collections, or local amphipod surveys (Feeley and Wass 1971). We have not found reports of C. terebrans in adjacent estuaries to the north and south e.g. Watling and Maurer (1972) for Delaware Bay, or Fox and Bynum (1975) for North Carolina. The limited range of this species in the Northwest Atlantic and Smith's (1879) early difficulty in locating populations, support the case for introduced status.

Invasion History Elsewhere in the World:

Chelura terebrans has become widely distributed in the world, presumably, by burrowing into the hulls of wooden ships. It appears to have become established primarily in temperate waters (Kuhne and Becker 1964). It was established in South Africa by 1889 (Kuhne and Becker 1964; Robinson et al. 2005), New Zealand by 1911 (Cranfield et al. 1998), eastern Australia by 1921 (Kuhne and Becker 1964), Egypt (at the Red Sea terminus of the Suez Canal) by 1928 (Kuhne and Becker 1964), and Hong Kong by 1911 (Kuhne and Becker 1964). It is also established in Bermuda (1903, Kuhne and Becker 1964; Yale Peabody Museum of Natural History 2015). Records of C. terebrans from Hawaii and the Virgin Islands probably refer to the Indo-Pacific species Tropichelura insulae (Barnard 1959; Wallour 1960; Carlton and Eldredge 2009).


The body of Chelura terebrans is depressed and cylindrical, and the posterior margins of its segment are lined with setae. Pleosome segment 3 is produced into a rearward-curving dorsal spine, which is especially large in males. The uropods are large, especially Uropod 3, in which the outer ramus is huge and paddle-like. In males, Uropod 3 is nearly as long as the body.

The head is broad and rounded, and a rostrum is absent. The eye is large and black, and located laterally. The antennae are short. Antenna 1 has a flagellum of 5-6 segments, with a 2-segmented accessory flagellum. Antenna 2 is longer and thicker than Antenna 1, and densely covered with setae. The flagellum consists of a single large, scale-like segment, and two minute segments.

Gnathopod 1 is not greatly enlarged in males or females, but is somewhat thicker, compared to Gnathopod 2. The 6th segment of Gnathopod 1 is longer than segment 5. Segments 2, 5 and 6 of Gnathopod 2 are lined with plume-like setae. As noted above, the rearward-projecting spine on the last pleosome segment is much larger in males than females. Each of the 3 pairs of uropods are dissimilar and also vary between males and females. Uropod 1 has a peduncle 2X the length of the rami, with the inner ramus expanded distally. In females, the peduncle and rami are stouter than in males. Uropod 2 is short, with a wing-like inner lobe on the margin of the peduncle with short rami. In males, the wing-like lobe is larger with more setae than in females. Uropod 3 has a short, broad peduncle, but a very long outer ramus, paddle-like in females, long and rudder-like in males. The telson is small and triangular. The body length is 3.5-6 mm, and the color is pale brown, mottled with pink. Description based on Allman 1847, Smith 1879, Barnard 1950, Bousfield 1973, Lincoln 1979, and Chapman 2007.


Taxonomic Tree

Kingdom:   Animalia
Phylum:   Arthropoda
Subphylum:   Crustacea
Class:   Malacostraca
Subclass:   Eumalacostraca
Superorder:   Peracarida
Order:   Amphipoda
Suborder:   Gammaridea
Family:   Cheluridae
Genus:   Chelura
Species:   terebrans


Potentially Misidentified Species

Nippochelura brevicauda
Misaki, Onagawa and Kominato, Japan (Barnard 1959)

Tropichelura insulae
Indo-Pacific Islands from Christmas Island, Indian Ocean to Honolulu; Caribbean from Costa Rica to Puerto Rico and Trinidad (Barnard 1959)



Chelura terebrans is an amphipod which usually lives within the burrows of wood-boring isopods of the genus Limnoria spp. (gribbles). Gammarid amphipods have separate sexes, brooded embryos, and direct development. Males and females mature at about 3.5 mm. Copulation takes place within burrows. Broods average about 4 embryos, but can range to up to 15, with as many as 5 broods in a lifetime. Embryo development takes ~47 days at 14C, and 18 days at 26C (Becker 1971), Juveniles develop in their parents' burrow and cannot burrow on their own. Young C. terebrans take ~70-84 days to mature at 20C (Bourdillon 1958a; Bourdillon 1958b; Kuhne and Becker 1964; Becker 1971).

Chelura terebrans tolerates a wide range of temperature (-2 to 26C), and occurs through the euhaline-polyhaline salinity range (Nair and Leivestad 1959; Kuhne and Becker 1964; Becker 1971). It has been found with L. lignorum, L. tripunctata, L. quadripunctata and Limnoria carinata (Bourdillon 1958a; Kuhne and Becker 1964; Borges 2010). The diet of C. terebrans consists largely of Limnoria fecal pellets. The feeding of C. terebrans helps keep the burrows clean, and its movements increase water circulation in the burrows. It prefers fungus-infected wood, and its boring activities mostly involve enlarging Limnoria's borrows (Kuhne and Becker 1964; Becker 1971). Green Extabe (2013) found that C. terebrans could be cultured indefinitely on Scots Pine wood, in the absence of Limnoria, and are capable of producing enzymes to digest wood, without depending on gut bacteria. Chelura terebrans disperses by swarming, usually in the spring, and also when their wooden habitat disintegrates (Bourdillon 1958a; Kuhne and Becker 1964; Becker 1971).


Bacteria; Protists; Decaying Wood

Trophic Status:




General HabitatCoarse Woody DebrisNone
General HabitatMarinas & DocksNone
General HabitatVessel HullNone
Salinity RangePolyhaline18-30 PSU
Salinity RangeEuhaline30-40 PSU
Tidal RangeSubtidalNone

Tolerances and Life History Parameters

Minimum Temperature (ºC)-2Experiments (Nair and Leivestad 1959)
Maximum Temperature (ºC)26Field Data (Kuhne and Becker 1964)
Minimum Salinity (‰)18Experiments (Nair and Leivestad 1959)
Maximum Salinity (‰)40Field Data (Kuhne and Becker 1964)
Minimum Reproductive Temperature15Experimental, lowest tested (Becker 1971)
Maximum Reproductive Temperature26Experimental (Becker 1971)
Minimum Length (mm)3.5Adults, Bourdillon 1958; Kuhne and Becker 1964
Maximum Length (mm)6Adults, Bourdillon 1958; Kuhne and Becker 1964
Broad Temperature RangeNoneCold temperate-Warm temperate
Broad Salinity RangeNonePolyhaline-Euhaline

General Impacts

Chelura terebrans is an amphipod which usually lives in association with wood-boring isopods of the genus Limnoria spp. (gribbles), living in the Limnoria burrows (Becker 1971). This amphipod is capable of digesting wood on its own (Green Etxabe 2015) but its impacts on natural wood and human structures appears to be small compared to shipworms and Limnoria. Most of its boring activity consists of enlarging Limnoria burrows (Atwood 1922; Brown 1953; Becker 1971).

Economic Impacts

Shipping- Chelura terebrans is regarded as an important wood-boring pest, although it is usually only a significant borer in the presence of Limnoria spp., and its damage consists mostly of enlarging Limnoria's burrows and speeding the latter's destruction of wooden pilings (Barnard 1955; Becker 1971; Kuhne and Becker 1964). As destroyers of wooden structures, crustacean borers as a group are regarded as second in importance to shipworms (Atwood 1922; Brown 1953). In the NW Atlantic, substantial populations of C. terebrans were found between Boston and Fisher's Island New York, (near New London, Connecticut), and in Hamilton Harbor, Bermuda. However, boring activity due to C. terebrans was considered minor (Brown 1953).

Chelura terebrans was first collected on the west coast of North America in 1949 in San Francisco and Los Angeles harbors (Barnard 1950). In Los Angeles-Long Beach Harbors, and harbors in San Francisco Bay, these amphipods were 'very abundant' on pilings (Barnard 1950); apparently increasing the size of burrows and the erosibility of wood (Barnard 1955).

Ecological Impacts

Herbivory, Habitat Change- Chelura terebrans together with the isopods Limnoria spp. (gribbles) play an important role in the decomposition and recycling of wood. Limnoria spp. burrow much more rapidly than C. terebrans, and the amphipod normally depends on its tunnels for shelter, which it enlarges (Barnard 1959; Kuhne and Becker 1964). The relationship between the isopods and amphipods is mutualistic in part, since C. terebrans cleans feces from the burrows and improves water circulation, but high densities can interfere with Limnoria populations (Kuhne and Becker 1964; Becker 1971).

Regional Impacts

P050San Pedro BayEconomic ImpactShipping/Boating
'Very abundant' in pilings (Barnard 1950); apparently increasing the size of burrows made by gribbles (Limnoria spp.) and the erosibility of wood (Barnard 1955)
P090San Francisco BayEconomic ImpactShipping/Boating
'Very abundant' in pilings (Barnard 1950); apparently increasing the size of burrows made by gribbles (Limnoria spp.) and the erosibility of wood (Barnard 1955)
NEP-VNorthern California to Mid Channel IslandsEconomic ImpactShipping/Boating
'Very abundant' in pilings (Barnard 1950); apparently increasing the size of burrows made by gribbles (Limnoria spp.) and the erosibility of wood (Barnard 1955)
NEP-VIPt. Conception to Southern Baja CaliforniaEconomic ImpactShipping/Boating
'Very abundant' in pilings (Barnard 1950); apparently increasing the size of burrows made by gribbles (Limnoria spp.) and the erosibility of wood (Barnard 1955)
CACaliforniaEconomic ImpactShipping/Boating
'Very abundant' in pilings (Barnard 1950); apparently increasing the size of burrows made by gribbles (Limnoria spp.) and the erosibility of wood (Barnard 1955), 'Very abundant' in pilings (Barnard 1950); apparently increasing the size of burrows made by gribbles (Limnoria spp.) and the erosibility of wood (Barnard 1955), 'Very abundant' in pilings (Barnard 1950); apparently increasing the size of burrows made by gribbles (Limnoria spp.) and the erosibility of wood (Barnard 1955)

Regional Distribution Map

Bioregion Region Name Year Invasion Status Population Status
AR-V None 0 Native Estab
NEA-II None 0 Native Estab
NEA-III None 0 Native Estab
NEA-IV None 0 Native Estab
NEA-V None 0 Native Estab
MED-I None 0 Native Estab
MED-II None 0 Native Estab
MED-III None 0 Native Estab
MED-IV None 0 Native Estab
MED-VII None 0 Native Estab
MED-VI None 0 Native Estab
MED-V None 0 Native Estab
MED-IX None 0 Native Estab
MED-VIII None 0 Native Estab
NA-ET3 Cape Cod to Cape Hatteras 1875 Def Estab
NA-ET2 Bay of Fundy to Cape Cod 1879 Def Estab
NA-ET4 Bermuda 1903 Def Estab
WA-V None 1889 Def Estab
WA-IV None 1921 Def Estab
RS-3 None 1928 Def Estab
NWP-2 None 1911 Def Estab
AUS-X None 1921 Def Estab
NZ-IV None 1914 Def Estab
NEP-V Northern California to Mid Channel Islands 1948 Def Estab
NEP-IV Puget Sound to Northern California 1960 Def Estab
NEP-VI Pt. Conception to Southern Baja California 1950 Def Estab
M040 Long Island Sound 1935 Def Estab
P050 San Pedro Bay 1950 Def Estab
M020 Narragansett Bay 1949 Def Estab
M010 Buzzards Bay 1875 Def Estab
P130 Humboldt Bay 2000 Def Estab
M130 Chesapeake Bay 1973 Def Unk
P090 San Francisco Bay 1948 Def Estab
P280 Grays Harbor 1960 Def Estab
N195 _CDA_N195 (Cape Cod) 1953 Def Estab
N180 Cape Cod Bay 1879 Def Estab
N170 Massachusetts Bay 1953 Def Estab
N100 Casco Bay 1953 Def Estab
AUS-XII None 1936 Def Estab
CAR-VII Cape Hatteras to Mid-East Florida 0 Def Unk
AUS-IV None 1971 Def Estab
AUS-VIII None 1986 Def Estab

Occurrence Map

OCC_ID Author Year Date Locality Status Latitude Longitude


Allman, George J. (1847) On Chelura terebrans Philippi, an amphipodous crustacean destructive to submarine timber-works, Annals and Magazine of Natural History 19: 361-370

Atwood, W. G. (1922) Marine borers, Proceedings of the American Society of Civil Engineers 48(6): 1408-1424

Bakir, Ahmet Kerem; Katagan, Tuncer (2014) Distribution of littoral benthic amphipods off the Levantine coast of Turkey with new records, Turkish Journal of Zoology 38: 23-34

Bakir, Kerem (2012) Contributions to the knowledge of crustaceans on soft bottoms in the Sea of Marmara, with a checklist, Crustaceana 85(2): 219-236

Bakir, Kerem; Katagan, Tuncer (2011) On the occurrence of Caprella scaura, Templeton, 1836 (Crustacea: Amphipoda) in Turkish waters, Zoology in the Middle East 52: 125-126

Barnard, J. Laurens (1950) The occurrence of Chelura terebrans Philippi in Los Angeles and San Francisco Harbors, Bulletin of the Southern California Academy of Sciences 49(2): 90-96

Barnard, J. Laurens (1955) The wood boring habits of Chelura terebrans Philippi in Los Angeles harbor, In: (Eds.) Essays in the Natural Sciences in Honor of Captain Allan Hancock. , Los Angeles. Pp. 87-95

Barnard, J. Laurens (1958) Amphipod crustaceans as fouling organisms in Los Angeles-Long Beach Harbors, with reference to the influence of seawater turbidity, California Fish and Game 44(2): 161-170

Barnard, J. Laurens (1959) Generic partition in the amphipod family Cheluridae, marine wood borers, Pacific Naturalist 1(3-4): 3-12

Becker, Gunther (1971) On the biology, physiology, and ecology of marine wood-boring crustaceans., In: Gareth Jones, E. B.//Eltringham, S. K.(Eds.) Marine borers, fungi, and fouling organisms of wood.. , Brussels. Pp. 303-326

Borges, L. M. S.; Valente, A. A.; Palma, P.; Nunes, L. (2010) Changes in the wood boring community in the Tagus Estuary: a case study, Marine Biodiversity Records 3: e41

Bourdillon, Andre (1958a) Biologie des crustaces marins xylophage, In: (Eds.) . , Paris. Pp. <missing location>

Bourdillon, Andre (1958b) La dissemination des crustaces xylophages Limnoria tripunctata Menzies et Chelura terebrans Philippi, Annee Biologique 34(11-12): 437-463

Bousfield, E.L. (1973) <missing title>, Comstock Publishing Associates, Ithaca, NY. Pp. <missing location>

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

Brown, Dorothy J. (1953) <missing title>, Report No. 8511 William F. Clapp Laboratories, Inc., Duxbury, Massachusetts. Pp. <missing location>

California Academy of Sciences 2005-2015 Invertebrate Zoology Collection Database. <missing URL>

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.; Eldredge, Lucius (2009) Marine bioinvasions of Hawaii: The introduced and cryptogenic marine and estuarine animals and plants of the Hawaiian archipelago., Bishop Museum Bulletin in Cultural and Environmental Studies 4: 1-202

Chapman, John W. (2007) The Light and Smith Manual: Intertidal invertebrates from Central California to Oregon (4th edition), University of California Press, Berkeley CA. Pp. 545-611

Christodoulou, Magdalini; Paraskevopoulou, Sofia; Syranidou, Evdokia; Koukouras, Athanasios (2013) The amphipod (Crustacea: Peracarida) fauna of the Aegean Sea, and comparison with those of the neighbouring seas, Journal of the Marine Biological Association of the United Kingdom 93(5): 1303-1327

Cohen, Andrew N. and 12 authors (2002) Project report for the Southern California exotics expedition 2000: a rapid assessment survey of exotic species in sheltered coastal waters., In: (Eds.) . , Sacramento CA. Pp. 1-23

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>

Coughlan, J. (1977) Marine borers in Southampton Water, Proceedings of the Hampshire Field Club and Archaeological Society 33: 5-15

Cranfield, H.J.; Gordon, D.P.; Willan, R.C.; Marshall, B.A; Battershill, C.N.; Francis, M.P.; Nelson, W.A.; Glasby, C.J.; Read, G.B. (1998) <missing title>, The National Institute of Water and Atmospheric Research, New Zealand. Pp. <missing location>

Feeley, James B.; Wass, Marvin L. (1971) The distribution and ecology of the Gammaridea (Crustacea: Amphipoda) of the lower Chesapeake estuaries., Special Papers in Marine Science 2: 1-58

Fox, Richard S.; Bynum, Kenneth H. (1975) The amphipod crustaceans of North Carolina estuarine waters, Chesapeake Science 16(4): 223-237

Green Etxabe, Amaia (2013) <missing title>, University of Portsmouth, <missing place>. Pp. 1-232

Haderlie, E. C. (1974) Wood-boring marine animals form the Gulf of Elat, Israel Journal of Zoology 23: 57-59

Johnson, Frederick, Stetson, Henry C., Parker, Frances L., Clench, William J., Nelson, Thurlow C., Linder, David H., Bailey, Irving W., Barghoorn, Els (1942) The Boylston Street fishweir, Papers of the Robert S. Peabody Foundation for Archaeology 2: 1-212

Kuhne, Helmut (1971) The identification of wood-boring crustaceans., In: Gareth Jones, E. B., and Eltringham. S.K.(Eds.) Marine Borers, Fungi, and Fouling Organisms of Wood.. , Paris. Pp. 65-88

Kuhne, Helmut; Becker, Gunther (1964) Der holz-flohkrebs Chelura terebrans Philippi (Amphipoda, Cheluridae), Beihefte Zeitschrift Angewandte Zoologie 1: 1-141

LeCroy, Sara E. (2004) <missing title>, 3 Florida Department of Environmental Protection, <missing place>. Pp. 411-500

Lincoln, Roger J. (1979) British Marine Amphipoda: Gammaridea., In: (Eds.) . , London. Pp. <missing location>

Mead, A.; Carlton, J. T.; Griffiths, C. L. Rius, M. (2011b) Introduced and cryptogenic marine and estuarine species of South Africa, Journal of Natural History 39-40: 2463-2524

Nair, N. Balakrishnan (1959) The marine timber-boring molluscs and crustaceans of western Norway, Arbok Universitet i Bergen 25: 1-23

Nair, N. Balakrishnan; Leivestad, Helge (1959) On the limiting factors in the distribution of two wood-boring crustaceans in Norway., Publications from the Biological Station, Espegrend 27: 1-12

Pillai, N. Krishna (1967) Proceedings of the symposium on Crustacea, Pt. V Marine Biological Association of India, <missing place>. Pp. 1274-1283

Robinson, T. B.; Griffiths, C. L.; McQuaid, C. D.; Rius, M. (2005) Marine alien species of South Africa-- status and impacts, African Journal of Marine Science 27(1): 297-306

Ruiz, Gregory M.; Geller, Jonathan (2018) Spatial and temporal analysis of marine invasions in California, Part II: Humboldt Bay, Marina del Re, Port Hueneme, and San Francisco Bay, Smithsonian Environmental Research Center & Moss Landing Laboratories, Edgewater MD, Moss Landing CA. Pp. <missing location>

Selin, N. V. Selin, N. I. (2015) Features of the spatial distribution of the Japanese Mud Shrimp Upogebia major (De Haan, 1841) (Decapoda: Upogebiidae) in the Vostok Bay, Sea of Japan, Russian Journal of Marine Biology 41: 219-222

Smith, S. I. (1879) The stalk-eyed crustaceans of the Atlantic coast of North American North of Cape Cod, Transactions of the Connecticut Academy of Arts and Sciences 5(1): 27-138

Smith, Sidney I. (1879) Occurrence of Chelura terebrans, a crustacean destructive to the timber of submarine structures, on the coast of the United States., Proceedings of the United States National Museum 2: 232-235

Sumner, Francis B.; Osburn, Raymond C.; Cole, Leon J.; Davis, Bradley M. (1913b) A biological survey of the waters of Woods Hole and vicinity Part II. Section III. A catalogue of the marine fauna Part II. Section IV. A catalogue of the marine flora, Bulletin of the Bureau of Fisheries 31: 539-860

U.S. National Museum of Natural History 2002-2021 Invertebrate Zoology Collections Database.

Wallour, Dorothy Brown (1960) Thirteenth progress report on marine borer activity in test boards operated during 1959, William F. Clapp Laboratories, Duxbury, Massachusetts. Pp. 1-41

Watling, Les (1979) Zoogeographic affinities of northeastern North American gammaridean amphipoda, Bulletin of the Biological Society of Washington <missing volume>(3): 256-282

Watling, Les; Maurer, Don (1972) Marine shallow water amphipods of the Delaware Bay area, U.S.A., Crustaceana <missing volume>: 251-266

Yale Peabody Museum of Natural History 2008-2016 YPM Invertebrate Zoology - Online Catalog. <missing URL>