Thalassiosira weissflogii (Grunow) G. Fryxell & Hasle, (1896) 1977

Common Name: A centric diatom

Synonyms and Other Names:

Coscinodiscus fallax, Contricribra weissflogii, Micropodiscus weissflogii, Thalassiosira fluviatilis

Gene StoermerCopyright Info

Identification: This cylindrical diatom occurs singly or in groups and may sometimes be found enveloped in a gelatinous matrix. The shape of the valve face varies. There is one labiate process and two or more central processes forming an irregular ring. The number of central processes, as well as the degree of silicification, are believed to vary with salinity. Irregularly shaped areolae, striations, a marginal ring of processes, a marginal ring of spines, and thick radial ribs may also occur on the valve face (Ferrario et al. 1989, Johansen and Theriot 1987, Kiss et al. 1984, Lee and Yoo 1986, Lowe and Busch 1975, Sala 1997, Vrieling et al. 1999).

Thalassiosira weissflogii can measure anywhere from 4–32 µm in diameter (Belcher and Swale 1977, Ferrario et al. 1989, Johansen and Theriot 1987, Kiss et al. 1984, Lee and Yoo 1986, Lomas and Glibert 1999, Lowe and Busch 1975, Richardson and Cullen 1995, Sala 1997).

Size: 4-32 microns in diameter

Native Range: Unclear. Thalassiosira weissflogii is considered widespread. It is known from European and Asian coastal waters and some inland rivers and reservoirs; rivers in North America; inland waters of South America; and Hawaii and the Solomon Islands (Belcher and Swale 1977, 1986; Ferrario et al. 1989; Lee and Yoo 1986; Lowe and Busch 1975; Mills et al. 1993; Sala 1997; Sivasubramanian and Rao 1988).

Map Key
This map only depicts Great Lakes introductions.

Great Lakes Nonindigenous Occurrences: Thalassiosira weissflogii was first recorded in 1962 from the Detroit River, which connects Lake St. Clair to Lake Erie. It was recorded from Lake Michigan in 1967, Lake Erie in the 1970s, and the Portage River in the Lake Erie drainage in 1973. It has also been recorded from Lake Ontario (Millie and Lowe 1981, Mills et al. 1993) and Lake Superior (US EPA 2008).

Table 1. Great Lakes region nonindigenous occurrences, the earliest and latest observations in each state/province, and the tally and names of HUCs with observations†. Names and dates are hyperlinked to their relevant specimen records. The list of references for all nonindigenous occurrences of Thalassiosira weissflogii are found here.

State/ProvinceFirst ObservedLast ObservedTotal HUCs with observations†HUCs with observations†
MI196219983Lake Erie; Lake Michigan; Lake Superior
NY199319982Lake Erie; Lake Ontario
OH197319992Cedar-Portage; Lake Erie
PA199619961Lake Erie
WI199819981Lake Michigan

Table last updated 6/13/2021

† Populations may not be currently present.

* HUCs are not listed for areas where the observation(s) cannot be approximated to a HUC (e.g. state centroids or Canadian provinces).

Ecology: Thalassiosira weissflogii occurs in freshwater, brackish, and marine habitats, especially at salinities above 5‰. Some experiments indicate that it grows best at higher salinities (Ferrario et al. 1989, Mills et al. 1993, Vrieling et al. 1999); this physiological requirement likely limits its distribution in the Great Lakes. It has been found occasionally in water from Lake Michigan subjected to chloride contamination (Stoermer and Yang 1969). It attained 74% phytoplankton abundance by biovolume in Lake Michigan during sampling in 1972-1973, although it only reached 11% abundance by biovolume in this lake during the 1973-1974 sampling period (Lauer 1976, Lauer and McComish 1976). Stoermer (1978) also reported T. weissflogii as a common diatom in the bays of Lakes Erie and Ontario.

Thalassiosira weissflogii is non-toxic but is often associated with assemblages that form blooms in red tides (Bricelj et al. 1991, Yamaoka et al. 1998). It can grow well at concentrations of 10% CO2, but at 20% CO2, its growth significantly decreases (Ishida et al. 2000). Growth rates tend to increase with increasing temperature (Lomas and Glibert 1999). It is also known to grow in waters with relatively high pH, around 8–9.4 (Sala 1997).

This species, like many other diatoms, is capable of a sexual reproduction phase. Moreover, the control of cell size is genetically linked to sexual reproduction. Cell size increases when sexual reproduction occurs and decreases when the asexual cycle begins. Sexual reproduction can be triggered either by reaching minimum cell size or by an external trigger such as changing light intensity (Armbrust 1999, Armbrust et al. 2001, Armbrust and Chisholm 1992, Sorhannus 2003).

Depending on its environment, various nutrients may be growth limiting or have a controlling effect on cell processes. These nutrients include nickel, zinc, iron, nitrogen, and silicon (Berges et al. 1996, De La Rocha and Passow 2004, Lee et al. 1995, Maldonado and Price 1996, Morel et al. 1994, Price and Morel 1991, Tortell and Price 1996).

Means of Introduction: Thalassiosira weissflogii was very likely introduced in ballast water to the Great Lakes basin (Mills et al. 1993).

Status: Established where recorded.

Great Lakes Impacts:

There is little or no evidence to support that Thalassiosira weissflogii has significant environmental impacts in the Great Lakes.

Outside the Great Lakes, T. weissflogii is one of several species that has been associated with red tides (Yamaoka et al 1998). In California, Thalassiosira sp. was reported to clog the gills of fish during these red tide events, which led to a reduction in fish populations (Núñez-Vázquez et al. 2011).

There is little or no evidence to support that Thalassiosira weissflogii has significant socio-economic impacts in the Great Lakes.

There is little or no evidence to support that Thalassiosira weissflogii has significant beneficial effect in the Great Lakes.
Thalassiosira weissflogii has a high lipid content, which makes it a viable option for mariculture (Ishida et al. 2000). Thalassiosira weissflogii also has a high tolerance for CO2, making it a good candidate for eliminating CO2 during treatment of emissions from industrial factories (Ishida et al. 2000).


Regulations (pertaining to the Great Lakes region)
There are no known regulations for this species.

Note: Check federal, state/provincial, and local regulations for the most up-to-date information.

There are no known biological control methods for this species.

There are no known physical control methods for this species.

Thalassiosira weissflogii struggles to grow or reproduce at salinities below 5‰ (Stoermer 1978). The reduction of  pollution from road salt run-off could decrease the viable habitat for T. weissflogii.

Note: Check state and local regulations for the most up-to-date information regarding permits for control methods. Follow all label instructions.

References: (click for full references)

Armbrust, E.V. 1999. Identification of a new gene family expressed during the onset of sexual reproduction in the centric diatom Thalassiosira weissflogii. Applied and Environmental Microbiology 65(7): 3121-3128.

Armbrust, E.V., and H.M. Galindo. 2001. Rapid evolution of a sexual reproduction gene in centric diatoms of the genus Thalassiosira. Applied and Environmental Microbiology 67(8): 3501-3513.

Armbrust, E.V., and S.W. Chisholm. 1992 Patterns of cell size change in a marine centric diatom: variability evolving from clonal isolates. Journal of Phycology 28: 146-156.

Belcher, J.H., and E.M.F. Swale. 1977. Species of Thalassiosira diatoms (Bacillariophyceae) in the plankton of English rivers. British Phycological Journal 12(3): 291-296.

Belcher, J.H., and E.M.F. Swale. 1986. Notes on some small Thalassiosira species (Bacillariophyceae) from the plankton of the lower Thames and other British estuaries identified by transmission electron microscopy. British Phycological Journal 21(2): 139-146.

Berges, J.A., D.O. Charlebois, D.C. Mauzerall, and P.G. Falkowski. 1996. Differential effects of nitrogen limitation on photosynthetic efficiency of photosystems I and II in microalgae. Plant Physiology (Rockville) 110(2): 689-696.

Bricelj, V.M., J.H. Lee, and A.D. Cembella. 1991. Influence of dinoflagellate cell toxicity on uptake and loss of paralytic shellfish toxins in the northern quahog Mercenara mercenaria. Marine Ecology Progress Series 74(1): 33-46.

De La Rocha, C.L., and U. Passow. 2004. Recovery of Thalassiosira weissflogii from nitrogen and silicon starvation. Limnology and Oceanography 49(1): 245-255.

Ferrario, M.E., R.G. Godina, and M.C. Domorenea. 1989. About some freshwater centric diatoms from Argentina. Iheringia Serie Botanica 39: 55-68. (in Spanish)

Ishida, Y., N. Hiragushi, H. Kitaguchi, A. Mitsutani, S. Nagai, and M. Yoshimura. 2000. A highly CO2 tolerant diatom, Thalassiosira weissflogi H1, enriched from coastal sea, and its fatty acid composition. Fisheries Science (Tokyo) 66(4): 655-659.

Johansen, J.R., and E. Theriot. 1987. The relationship between valve diameter and number of central fultoportulae in Thalassiosira weissflogii (Bacillariophyceae). Journal of Phycology 23: 663-665.

Kiss, K.T., K. Kovacs, and E. Dobler. 1984. The fine structure of some Thalassiosira spp. (Bacillariophyceae) in the Danube and the Tisza Rivers, Hungary. Archiv für Hydrobiologie Supplement 67(4): 409-415.

Lauer, T.E. 1976. Principal components ordination of southern Lake Michigan USA phytoplankton. Journal of Phycology 12(suppl.): 8-9.

Lauer, T.E., and T.S. McComish. 1976. Phyto plankton population dynamics of the inshore waters of southern Lake Michigan near Michigan City, Indiana, USA, from June 1973 to May 1974. Proceedings of the Indiana Academy of Science 85: 151.

Lee, J.G., S.B. Roberts, and F.M.M. Morel. 1995. Cadmium: a nutrient for the marine diatom Thalassiosira weissflogii. Limnology and Oceanography 40(6): 1056-1063.

Lee, J.H., and K.I. Yoo. 1986. A study on the fine structure of the marine diatoms of Korean coastal waters, genus Thalassiosira. Journal of the Korean Society of Oceanography 21(3): 184-192.

Lomas, M.W., and P.M. Glibert. 1999. Interactions between NH4+ and NO3- uptake and assimilation: comparison of diatoms and dinoflagellates at several growth temperatures. Marine Biology 133: 541-551.

Lowe, R.L., and D.E. Busch. 1975. Morphological observations on two species of the diatom genus Thalassiosira from fresh-water habitats in Ohio. Transactions of the American Microscopical Society 94(1): 118-123.

Maldonado, M.T., and N.M. Price. 1996. Influence of N substrate on Fe requirements of marine centric diatoms. Marine Ecology Progress Series 141: 161-172.

Millie, D.F., and R.L. Lowe. 1981. Diatoms new to Ohio and the Laurentian Great Lakes. Ohio Journal of Science 81(5): 195-206.

Mills, E.L., J.H. Leach, J.T. Carlton, and C.L. Secor. 1993. Exotic species in the Great Lakes: a history of biotic crises and anthropogenic introductions. Journal of Great Lakes Research 19(1): 1-54.

Morel, F.M.M., J.R. Reinfelder, S.B. Roberts, C.P. Chamberlain, J.G. Lee, and D. Yee. 1994. Zinc and carbon co-limitation of marine phytoplankton. Nature (London) 369(6483): 740-742.

Núñez-Vázquez, E.J., I. Gárate-Lizarraga, C.J. Band-Schmidt, A. Cordero-Tapia, D.J. Lopez-Cortes, F.E. Hernandez-Sandoval, A. Heredia-Tapia, and J.J. Bustillos-Guzman. 2011. Impact of harmful algal blooms on wild and cultured animals in the Gulf of California. Journal of Environmental Biology 32(4): 413-423.

Price, N.M., and F.M.M. Morel. 1991. Colimitation of phytoplankton growth by nickel and nitrogen. Limnology and Oceanography 36(6): 1071-1077.

Richardson, T.L., and J.J. Cullen. 1995. Changes in buoyancy and chemical composition during growth of a coastal marine diatom: ecological and biogeochemical consequences. Marine Ecology Progress Series 128(1-3): 77-90.

Sala, S.E. 1997. Diatom flora of Paso de las Piedras impounding, Buenos Aires Province IV: Order Centrales. Gayana Botanica 54(1): 1-14. (in Spanish)

Sivasubramanian, V., and V.N.R. Rao. 1988. Uptake and assimilation of nitrogen by marine diatoms I. Kinetics of nitrogen uptake. Proceedings of the Indian Academy of Sciences, Plant Sciences 98(2): 71-88.

Sorhannus, U. 2003. The effect of positive selection on a sexual reproduction gene in Thalassiosira weissflogii (Bacillariophyta): results obtained from maximum-likelihood and parsimony-based methods. Molecular Biology and Evolution 20(8): 1326-1328.

Tortell, P.D., and N.M. Price. 1996. Cadmium toxicity and zinc limitation in centric diatoms of the genus Thalassiosira. Marine Ecology Progress Series 138(1-3): 245-254.
U.S. Environmental Protection Agency (US EPA). 2008. EPA Great Lakes National Program Office. EPA Monitoring Data.

Vrieling, E.G., L. Poort, T.P.M. Beelen, and W.W.C. Gieskes. 1999. Growth and silica content of the diatoms Thalassiosira weissflogii and Navicula salinarum at different salinities and enrichments with aluminium. European Journal of Phycology 34: 307-316.

Yamaoka, Y., O. Takimura, H. Fuse, K. Murakami, S. Kitao, M. Saeki, S. Watanuki, and M. Aihara. 1998. Growth of red tide phytoplankton using glass powder containing nutrients. Technical note. Seibutsu-Kogaku Kaishi 76(4): 153-157.

Author: Kipp, R.M., M. McCarthy, and A. Fusaro

Contributing Agencies:

Revision Date: 9/12/2019

Citation for this information:
Kipp, R.M., M. McCarthy, and A. Fusaro, 2021, Thalassiosira weissflogii (Grunow) G. Fryxell & Hasle, (1896) 1977: U.S. Geological Survey, Nonindigenous Aquatic Species Database, Gainesville, FL, and NOAA Great Lakes Aquatic Nonindigenous Species Information System, Ann Arbor, MI,, Revision Date: 9/12/2019, Access Date: 6/23/2021

This information is preliminary or provisional and is subject to revision. It is being provided to meet the need for timely best science. The information has not received final approval by the U.S. Geological Survey (USGS) and is provided on the condition that neither the USGS nor the U.S. Government shall be held liable for any damages resulting from the authorized or unauthorized use of the information.