.JPG)
Invasion History
First Non-native North American Tidal Record: 1894First Non-native West Coast Tidal Record: 1894
First Non-native East/Gulf Coast Tidal Record:
General Invasion History:
The native range of Geukensia demissa spans from the southern Gulf of St. Lawrence to Palm Beach, Florida (Bousfield 1960; Abbott 1974; Morris 1975; Gosner 1978; Krisberg 2009). The Gulf Ribbed Mussel (Geukensia granossisima), formerly considered a subspecies of G. demissa occurs from northwest Florida to Texas (Sarver et al. 1992). Specimens introduced to the West Coast have been identified as G. demissa by molecular methods (Sarver et al. 1992).
North American Invasion History:
Invasion History on the West Coast:
Geukensia demissa was first collected on the West Coast in South San Francisco Bay in 1894 (Carlton 1979). It was introduced with plantings of Eastern Oysters (Miller 2007). It is now one of the most abundant bivalves in San Francisco Bay, from San Pablo Bay to South Bay, where it lines the edges of salt-marsh creeks, channel banks, and retaining walls, attached to the substrate or plant roots by byssus threads (Carlton 1979; Cohen and Carlton 1995). One specimen was collected in Tomales Bay, California (CA) in 1952, and there are other unverified records, for instance, it was reported from Tomales Bay by Fairey et al. (2002), based on a 2001 survey. This mussel was found in 1986 in Morro Bay, CA but was not reported during subsequent surveys in 2001 (Needles 2007). In Southern California, G. demissa was found in Newport Bay in 1955, Alamitos Bay in 1968 (Reish 1968, cited by Carlton 1979; 2000, Cohen et al. 2002; Burnaford et al. 2011), Anaheim Bay in 1972 (Reish 1972, cited by Carlton 1979), and the adjacent Bolsa Chica Lagoon in 1992 (Carlton 1992). Occurrences in southern California could be associated with Eastern Oyster transfers, but the documented transfers were few and small. Introductions with ballast water or fouling are possible. Further south, it is established and very abundant in Estero de Punta Banda, Baja California Norte, Mexico, where it was introduced by the early 1980s (Torchin et al. 2005).
Invasion History Elsewhere in the World:
Geukensia 'demissa' has been reported and studied in Lake Maracaibo, Venezuela, where it was introduced by 1994, and is now established (Romero et al. 2003; Baez et al. 2005). However, these records could refer to G. granossisima (Gulf Ribbed Mussel), which was formerly considered conspecific with G. demissa.
Description
Geukensia demissa has a moderately thin, oblong-oval shell. The outer surface is marked by numerous strong radial ribs with widely spaced growth lines. The beak of the shell is subterminal, located somewhat above the hinge of the shell. Hinge teeth are absent. The ventral portion of the shell is slightly curved inward. The exterior color is yellowish-green to bluish brown, while the interior is silvery white, and often iridescent. Adult mussels range from 20 to 1400 mm (Abbott 1974; Brousseau 1984; Coan et al. 2000; Coan and Vantich-Scott 2007). Larvae are described and illustrated by Chanley and Andrews (1971). The larvae are planktotrophic, and settle at 215-305 µm (Chanley and Andrews 1971).
Taxonomy
Taxonomic Tree
| Kingdom: | Animalia | |
| Phylum: | Mollusca | |
| Class: | Bivalvia | |
| Subclass: | Pteriomorphia | |
| Order: | Mytiloida | |
| Family: | Mytilidae | |
| Genus: | Geukensia | |
| Species: | demissa |
Synonyms
Arcuatula demissa (None, None)
Brachidontes demissus (None, None)
Ischadium demissum (None, None)
Modioulus plicatulus (Lamarck, 1819)
Volsella demissus (None, None)
Brachidontes demissus (None, None)
Ischadium demissum (None, None)
Modioulus plicatulus (Lamarck, 1819)
Volsella demissus (None, None)
Potentially Misidentified Species
Geukensia granossisima
(Sowerby 1914). Gulf Ribbed Mussel- this species had been regarded as a subspecies of G. demissa, but molecular analysis (enzyme electrophoresis) indicates that G. granossisimma and G. demissa are separate species (Sarver et al. 1992; Lee and O'Foighil 2004). Photographs posted by Krisberg (2009) show strong morphological differences between the forms, with a more hooked shape in G. granosissima, resembling mussels of the genus Ischadium, a similarity supported by molecular evidence (Lee and O'Foighil 2004).
Ischadium recurvum
Hooked Mussel- Young specimens are similar, but show strong curvature with growth.
(Sowerby 1914). Gulf Ribbed Mussel- this species had been regarded as a subspecies of G. demissa, but molecular analysis (enzyme electrophoresis) indicates that G. granossisimma and G. demissa are separate species (Sarver et al. 1992; Lee and O'Foighil 2004). Photographs posted by Krisberg (2009) show strong morphological differences between the forms, with a more hooked shape in G. granosissima, resembling mussels of the genus Ischadium, a similarity supported by molecular evidence (Lee and O'Foighil 2004).
Ischadium recurvum
Hooked Mussel- Young specimens are similar, but show strong curvature with growth.
Ecology
General:
Geukensia demissa has separate sexes. Animals mature at about one year of age. Sexes differ in the color of the mantle, with females being yellowish brown, while males are a cream color. Eggs are brooded, but sperm are released into the water column. Fertilized eggs develop into a planktonic trochophore larva, then into a shelled veliger. The larvae settle at 220-300 µm (Chanley and Andrews 1971).
Geukensia demissa larvae settle on rocks, wood, roots of marsh plants, and peat, though they are most abundant in marsh habitats (Abbott 1974; Morris 1975; Gosner 1978; Lippson and Lippson 1997). Marsh populations tolerate water temperatures from -1.8 to 37⁰C (Read and Cumming 1967, cited by Hicks and McMahon 2002), and doubtless survive higher air temperatures. They also tolerate wide ranges of salinity, from 5 to 70 PSU (Smithsonian Marine Station at Fort Pierce 2011).
Food:
Phytoplankton; Detritus
Consumers:
Birds, California Clapper Rail
Trophic Status:
Suspension Feeder
SusFedHabitats
| General Habitat | Unstructured Bottom | None |
| General Habitat | Oyster Reef | None |
| General Habitat | Marinas & Docks | None |
| General Habitat | Salt-brackish marsh | None |
| General Habitat | Vessel Hull | None |
| Salinity Range | Mesohaline | 5-18 PSU |
| Salinity Range | Polyhaline | 18-30 PSU |
| Salinity Range | Euhaline | 30-40 PSU |
| Tidal Range | Low Intertidal | None |
| Tidal Range | Mid Intertidal | None |
| Vertical Habitat | Epibenthic | None |
| Vertical Habitat | Endobenthic | None |
Tolerances and Life History Parameters
| Minimum Temperature (ºC) | -2 | Based on geographical range |
| Maximum Temperature (ºC) | 37 | Experimental, ranges of 35-37 reported by Read and Cumming (1967), cited by Hicks and McMahon (2002) |
| Minimum Salinity (‰) | 5 | Field record (Miller 2000), Experimental, stepwise decrease (Wells 1961) |
| Maximum Salinity (‰) | 70 | Smithsonian Marine Station at Fort Pierce 2011. |
| Minimum Reproductive Temperature | 20 | Field data, North Carolina (Borerro 1987) |
| Maximum Reproductive Temperature | 28 | Field data, North Carolina (Borerro 1987) |
| Minimum Duration | 12 | Lab reared at 22 C (Loosanoff and Davis 1963) |
| Maximum Duration | 43 | Lab reared at 22 C (Loosanoff and Davis 1963) |
| Minimum Length (mm) | 20 | Minimum Adult Size (Brousseau 1984) |
| Maximum Length (mm) | 140 | Maximum Adult Size (Brousseau 1984) |
| Broad Temperature Range | None | Cold temperate-Subtropical |
| Broad Salinity Range | None | Mesohaline-Euhaline |
General Impacts
Geukensia demissa is very abundant in San Francisco Bay, California. Possible economic impacts include structural effects on marsh channels and dikes. Since these mussels constitute a very large biomass, they could have a significant ecological impact by filtering phytoplankton and competing for food with native bivalves. Some of these impacts also appear probable in Estero Puerto Bando, Mexico, based on field studies by Torchin et al. (2005). However, economic and ecological (experimental) studies of G. demissa have not been conducted in its introduced range.Ecological Impacts
Habitat Change- High densities of G. demissa in Estero de Punta Banda, Mexico, appear to facilitate growth of the native Pacific cordgrass Spartina foliosa, based on correlation of density of the two organisms (Torchin et al. 2005). The Ribbed Mussels also have a rather unusual impact on a native, endangered, bird. The rapidly closing shells of the mussels can trap chicks and sever toes of adult California Clapper Rails (Rallus longirostris obsoletus) in salt marshes (Carlton 1979; Cohen and Carlton 1995). Geukensia demissa represents a similar threat to another endangered subspecies, R. l. levipes, (Light-Footed Clapper Rail) in Estero Bando (Torchin et al., 2005).
Food/Prey- However, this abundant mussel is also a major food source for the California Clapper Rail (Moffitt 1941, cited by Cohen and Carlton 1995) and doubtless for other wading birds, raccoons, otters, and other salt-marsh predators.
Regional Impacts
| NEP-V | Northern California to Mid Channel Islands | Ecological Impact | Habitat Change | ||
| Closing shells can trap chicks and sever toes of adult endangered California Clapper Rails (Rallus longirostris obsoletus) in salt marshes (Carlton 1979; Cohen and Carlton 1995). | |||||
| P090 | San Francisco Bay | Ecological Impact | Habitat Change | ||
| Closing shells can trap chicks and sever toes of adult endangered California Clapper Rails (Rallus longirostris obsoletus) in salt marshes (Carlton 1979; Cohen and Carlton 1995). | |||||
| NEP-VI | Pt. Conception to Southern Baja California | Ecological Impact | Habitat Change | ||
| High densities of G. demissa in Estero de Punta Banda, Baja California Norte, Mexico, appear to facilitate growth of the native Pacific cordgrass Spartina foliosa. They also present a hazard to the endangered Light-footed Clapper Rail (Rallus longirostrus levipes), in Estero Puerto Bando, based on the damage seen to the subspecies (R. l. oboletus) in San Francisco Bay (Torchin et al. 2005). | |||||
| NEP-VI | Pt. Conception to Southern Baja California | Ecological Impact | Competition | ||
| Based on the very high biomass seen in Estero de Punta Banda (4 X that of the next most abundant and native species, Tagelus spp.), competition for phytoplankton and other suspended food particles is likely (Torchin et al. 2005). | |||||
| NEP-V | Northern California to Mid Channel Islands | Ecological Impact | Food/Prey | ||
| Geukensia demissa comprised 57% of the diet of the endangered California Clapper Rail (Rallus longirostris obsoletus) (Moffitt 1941, cited by Cohen and Carlton 1995). | |||||
| P090 | San Francisco Bay | Ecological Impact | Food/Prey | ||
| Geukensia demissa comprised 57% of the diet of the endangered California Clapper Rail (Rallus longirostris obsoletus) (Moffitt 1941, cited by Cohen and Carlton 1995). | |||||
| CA | California | Ecological Impact | Food/Prey | ||
| Geukensia demissa comprised 57% of the diet of the endangered California Clapper Rail (Rallus longirostris obsoletus) (Moffitt 1941, cited by Cohen and Carlton 1995)., Geukensia demissa comprised 57% of the diet of the endangered California Clapper Rail (Rallus longirostris obsoletus) (Moffitt 1941, cited by Cohen and Carlton 1995). | |||||
| CA | California | Ecological Impact | Habitat Change | ||
| Closing shells can trap chicks and sever toes of adult endangered California Clapper Rails (Rallus longirostris obsoletus) in salt marshes (Carlton 1979; Cohen and Carlton 1995)., Closing shells can trap chicks and sever toes of adult endangered California Clapper Rails (Rallus longirostris obsoletus) in salt marshes (Carlton 1979; Cohen and Carlton 1995). | |||||
Regional Distribution Map
| Bioregion | Region Name | Year | Invasion Status | Population Status |
|---|---|---|---|---|
| NA-ET1 | Gulf of St. Lawrence to Bay of Fundy | 0 | Native | Estab |
| NA-S3 | None | 0 | Native | Estab |
| NA-ET2 | Bay of Fundy to Cape Cod | 0 | Native | Estab |
| NA-ET3 | Cape Cod to Cape Hatteras | 0 | Native | Estab |
| CAR-VII | Cape Hatteras to Mid-East Florida | 0 | Native | Estab |
| NEP-V | Northern California to Mid Channel Islands | 1894 | Def | Estab |
| NEP-VI | Pt. Conception to Southern Baja California | 1955 | Def | Estab |
| CAR-III | None | 1994 | Def | Estab |
| P040 | Newport Bay | 1955 | Def | Estab |
| P050 | San Pedro Bay | 1968 | Def | Estab |
| P090 | San Francisco Bay | 1894 | Def | Estab |
| P110 | Tomales Bay | 2001 | Def | Estab |
| P093 | _CDA_P093 (San Pablo Bay) | 1894 | Def | Estab |
| P070 | Morro Bay | 1986 | Def | Unk |
| P029 | _CDA_P029 (Newport Bay) | 1944 | Def | Estab |
| P058 | _CDA_P058 (San Pedro Channel Islands) | 2011 | Def | Unk |
Occurrence Map
| OCC_ID | Author | Year | Date | Locality | Status | Latitude | Longitude |
|---|---|---|---|---|---|---|---|
| 7876 | Carlton 1992 | 1997 | 1979-01-01 | Bolsa Chica Lagoon | Def | 33.6922 | -118.0398 |
| 7877 | Torchin et al. 2005 | 1985 | 1985-01-01 | Estero de Punta Banda | Def | 31.7500 | -116.6167 |
| 7878 | Romero et al. 2003 | 2002 | 2002-01-01 | Lake Maracaibo | Def | 10.9000 | -71.8000 |
| 7879 | Baez et al. 2005) | 2001 | 2001-01-01 | El Mojan | Def | 10.9167 | -71.7500 |
| 7880 | Bousfield 1960 | None | 9999-01-01 | Chaleur Bay | Native | 48.0000 | -66.0000 |
| 7881 | Bousfield 1960) | None | 9999-01-01 | Cape Breton Island | Native | 46.0000 | -61.5000 |
| 7882 | Academy of Natural Sciences of Philadelphia 2003 | None | 9999-01-01 | Charlottetown | Native | 46.2400 | -63.1399 |
| 7883 | Academy of Natural Sciences of Philadelphia 2003 | None | 9999-01-01 | Random Island | Native | 48.1167 | -53.7333 |
| 7884 | Bousfield 1960 | None | 9999-01-01 | St. Marys Bay | Native | 44.4167 | -66.1000 |
| 7889 | Bousfield 1960 | None | 9999-01-01 | Minas Basin | Native | 45.2500 | -64.1667 |
| 7890 | U.S. National Museum of Natural History 2012) | None | 9999-01-01 | Glen Haven, SW Of Halifax | Native | 44.5833 | -64.0000 |
| 7891 | U.S. National Museum of Natural History 2012 | None | 9999-01-01 | Bluff Hill Cove | Native | 41.3845 | -71.5012 |
| 7892 | U.S. National Museum of Natural History 2012 | None | 9999-01-01 | New Rochelle, Colony Beach Club | Native | 40.9115 | -73.7824 |
| 7893 | U.S. National Museum of Natural History 2012 | None | 9999-01-01 | Lewes, At Henlopen Flats | Native | 38.8032 | -75.0946 |
| 7894 | U.S. National Museum of Natural History 2012 | None | 9999-01-01 | Lockwoods Folly Inlet | Native | 33.9200 | -78.2300 |
| 7895 | U.S. National Museum of Natural History 2012 | None | 9999-01-01 | off Georgia | Native | 31.3933 | -80.8867 |
| 7896 | U.S. National Museum of Natural History 2012 | None | 9999-01-01 | Off Florida | Def | 25.7561 | -83.7036 |
| 7897 | Academy of Natural Sciences oif Philadelphia 2012 | None | 9999-01-01 | Woodland Beach | Native | 39.3334 | -75.4746 |
| 7898 | Academy of Natural Sciences of Philadelphia | None | 9999-01-01 | Benedict | Native | 38.5333 | -76.7167 |
| 7899 | Academy of Natural Sciences of Philadelphia 2012 | None | 9999-01-01 | Brigantine Island | Native | 39.4833 | -74.3333 |
| 7900 | Academy of Natural Sciences of Philadelphia 2012 | None | 9999-01-01 | Saint Augustine | Native | 29.7000 | -81.2167 |
| 7901 | Yale Peabody Museum 2012 | None | 9999-01-01 | Oyster Creek | Native | 44.0987 | -69.4920 |
References
Abbott, R. Tucker (1974) American Seashells, Van Nostrand Reinhold, New York. Pp. <missing location>Academy of Natural Sciences of Philadelphia 2002-2024a Malacology Collection Search. <missing URL>
Baez, Maria, de Severyn, Yajaira; Severyn, Hector (2005) Reproductive cycle of Geukensia demissa (Bivalvia : Mytilidae) on a beach at Nazaret, El Mojan, Zulia State, Venezuela, Ciencias Marinas 31: 111-118
Bertness, Mark D. (1999) <missing title>, Sinauer Associates, Sunderland MA. Pp. 417
Borrero, Francisco J. (1987) Tidal height and gametogenesis: reproductive variation among populations of Geukensia demissa, Biological Bulletin 173: 160-168
Bousfield, E. L. (1960) Canadian Atlantic Sea Shells, In: (Eds.) . , Ottawa. Pp. <missing location>
Bousfield, E. L. (1969) New records of Gammarus (Crustacea: Amphipoda) from the Middle Atlantic region, Chesapeake Science 10: 1-17
Brousseau, Diane J. (1984) Age and growth rate determinations for the Atlantic ribbed mussel, Geukensia demissa Dillwyn (Bivalvia: Mytilidae), Estuaries 7(3): 233-241
Burnaford, Jennifer L.; Henderson, Scottie Y. Pernet, Bruno (2011) Assemblage shift following population collapse of a non-indigenous bivalve in an urban lagoon, Marine Biology 158: 1915-1927
California Department of Fish and Wildlife (2014) Introduced Aquatic Species in California Bays and Harbors, 2011 Survey, California Department of Fish and Wildlife, Sacramento CA. Pp. 1-36
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. (1992) Introduced marine and estuarine mollusks of North America: An end-of-the-20th-century perspective., Journal of Shellfish Research 11(2): 489-505
Castagna, M.; Chanley, P. (1973) Salinity tolerance of some marine bivalves from inshore and estuarine environments in Virginia waters on the western mid-Atlantic coast., Malacologia 12(1): 47-96
Chanley, Paul; Andrews, J. D. (1971) Aids for identification of bivalve larvae of Virginia, Malacologia 11(1): 45-119
Coan, Eugene V.; Valentich-Scott, Paul (2007) The Light and Smith Manual: Intertidal Invertebrates from Central California to Oregon, University of California Press, Berkeley CA. Pp. 807-859
Coan, Eugene V.; Valentich-Scott, Paul; Bernard, Frank R. (2000) Bivalve Seashells of Western North Ameira, Santa Barbara Museum of Natural history, Santa Barbara CA. Pp. <missing location>
Cohen, A. N. and 11 authors (2005) Rapid assessment survey for exotic organisms in southern California bays and harbors, and abundance in port and non-port areas., Biological Invasions 7: 995-1002
Cohen, Andrew N. 2005-2024 Exotics Guide- Non-native species of the North American Pacific Coat. https://www.exoticsguide.org/
Cohen, Andrew N. and 10 authors (2005) <missing title>, San Francisco Estuary Institute, Oakland CA. Pp. <missing location>
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>
Fairey, Russell; Dunn, Roslyn; Sigala, Marco; Oliver, John (2002) Introduced aquatic species in California's coastal waters: Final Report, California Department of Fish and Game, Sacramento. Pp. <missing location>
Garthwaite, Ronald (1986) The genetics of California populations of Geukensia demissa: further evidence on selective importance of leucine aminopeptidase in salinity acclimation, Biological Journal of the Linnean Society 28: 343-358
Gedan, Keryn B.; Kellogg, Lisa; Breitburg, Denise L. (2014) Accounting for multiple foundation species in oyster reef restoration benefits, Restoration Ecology 22(4): 517-524
Gosner, Kenneth L. (1978) A field guide to the Atlantic seashore., In: (Eds.) . , Boston. Pp. <missing location>
Hicks, D. W.; McMahon, R. F. (2002) Temperature acclimation of upper and lower thermal limits and freeze resistance in the nonindigenous brown mussel, Pern perna (L.), from the Gulf of Mexico., Marine Biology 140: 1167-1179
Kim, Daemin; Taylor, Andrew T.; Near, Thomas J. (2022) Phylogenomics and species delimitation of the economically important Black Basses (Micropterus), Scientific Reports 12(9113): Published online
https://doi.org/10.1038/s41598-022-11743-2
Krisberg, Marlo F. 2009 Let's talk seashells- <i>Geukensia granosissima</i>. <missing URL>
Lee, Harry 2001-2015 Harry Lee's Florida Mollusca Checklists. <missing URL>
Lee. T. ; Ó Foighil, D. (2004) Hidden Floridian biodiversity: mitochondrial and nuclear gene trees reveal four cryptic species within the scorched mussel, Brachidontes exustus, species complex, Molecular Ecology 13: 3527-3542
Loosanoff, V. L. (1955) The European oyster in American waters, Science 121: 119-121
Low-Pfeng, Antonio; Recagno, Edward M. Peters (2012) <missing title>, Geomare, A. C., INESEMARNAT, Mexico. Pp. 236
Miller, A. Whitman; Ruiz, Gregory M.; Minton, Mark S.; Ambrose, Richard F. (2007) Differentiating successful and failed molluscan invaders in estuarine ecosystems., Marine Ecology Progress Series 332: 41-51
Morris, Percy A. (1975) A field guide to shells of the Atlantic, Houghton-Mifflin, Boston. Pp. <missing location>
Needles, Lisa A. (2007) <missing title>, M.S. Thesis, California Polytechnic State University, San Luis Obispo. Pp. <missing location>
Needles, Lisa A.; Wendt, Dean E. (2013) Big changes to a small bay: Introduced species and long-term compositional shifts to the fouling community of Morro Bay (CA), Biological Invasions 15(6): 1231-1251
Reish, Donald J.; Kauwling, Thomas J.; Schreiber, Traynor C. (1975) Annotated checklist of the marine invertebrates of Anaheim Bay, California Department of Fish and Game Fish Bulletin 165: 41-51
Robinson, April; Cohen, Andrew N.; Lindsey, Brie; Grenier, Letitia (2011) Distribution of macroinvertebrates across a tidal gradient, Marin County, California, San Francisco Estuary and Watershed Science 9(3): published online
Romero, J.; Severeyn, H.; García de Severeyn, Y. (2003) Geukensia demissa, new species for the Venezuelan malacological fauna, Revista de Biologia Tropical 51(1): published online
Sarver, S. K.; Landrum, M. C.; Foltz, D. W. (1992) Genetics and taxonomy of ribbed mussels (Geukensia spp., Marine Biology 113: 385-390
Scribano, Giovanni ; Marchini, Agnese; Ros, Macarena (2021) Population dynamics and life history traits of the non-indigenous Paranthura japonica,/em> Richardson (1909) in a recently invaded Mediterranean site, Regional Studies in Marine Science 46(101883): Published
Smithsonian Marine Station at Fort Pierce 2007-2022 Indian River Species Inventory. https://www.irlspecies.org/index.php
Sylvester, Francisco and 8 authors (2011) Hull fouling as an invasion vector: can simple models explain a complex problem?, Journal of Applied Ecology 48: 415-423
Torchin, Mark E.; Hechinger, Ryan F.; Huspeni, Todd C.; Whitney, Kathleen L.; Lafferty, Kevin D. (2005) The introduced ribbed mussel (Geukensia demissa) in Estero de Punta Banda, Mexico: interactions with the native cord grass, Spartina foliosa., Biological Invasions 7: 607-614
U.S. National Museum of Natural History 2002-2021 Invertebrate Zoology Collections Database. http://collections.nmnh.si.edu/search/iz/
Wells, Harry W. (1961) The fauna of oyster beds, with special reference to the salinity factor, Ecological Monographs 31: 239-266
Yale Peabody Museum of Natural History 2008-2016 YPM Invertebrate Zoology - Online Catalog. <missing URL>