Yellow sandshells (Lampsilis teres) are mainly located in the United States, however they do reach northern parts of Mexico as well. Yellow sandshells are native to parts of Mexico such as Coahuila and Nuevo León. In the United States, these mollusks are native from Minnesota to Texas, Nebraska to New York, and Florida to Kansas. This species appears in the Mississippi River drainage and the Gulf drainages as well. Lampsilis teres spans from the Rio Grande to the Withlacoochee River in Florida. (Cummings and Cordeiro, 2013)
The yellow sandshell occupies a variety of aquatic habitats. They have been reported in small streams, large rivers and oxbow lakes. Ponds, sloughs and reservoirs have also been known to provide a suitable environment for L. teres. Yellow sandshells may reside in fine sediments or they may be present in coarse substrates as well. Water conditions may range from clear to turbid, and substrates vary from rocky to muddy. Yellow sandshells may be found in slow or fast moving currents, and their preferred habitat is along the banks of muddy or silty rivers. ("Species profile:Minnesota DNR", 2014; Roe, 2010)
The yellow sandshell's exterior is yellow and shiny. Occasionally they contain green rays, especially in the young ones. The yellow sandshell has a stout, elongate, smooth shell that can reach up to 190 mm long. The posterior end of the shell is pointed in males, and somewhat truncate in females. The differences in structure between males and females clearly show that L. teres is a species that represents sexual dimorphism. The beak sculpture consists of fine and wavy ridges that are spaced very close together. Lampsilis teres has pseudocardinal teeth that elongate and are compressed, with two in the left valve and one in the right. They also have long, straight to slightly curved lateral teeth. The pseudocardinal and lateral teeth are well-developed, and the inner shell is white. Their beak cavity is somewhat deep and their nacre is white and silver.
The yellow sandshell resembles the black sandshell (Ligumia recta), the fat mucket (Lampsilis siliquoidea), and the pondmussel (Liqumia subrostrata). The yellow sandshell's beak sculpture and color distinguish it from the black sandshell, while its has a much narrower shell than the fat mucket. Yellow sandshells can be distinguished from the pondmussel by their color, size, and thickness. (Johnson, et al., 2001; "Species profile:Minnesota DNR", 2014; "Lampsilis teres (Rafinesque, 1820) Yellow Sandshell", 2014)
In the wild, male yellow sandshells (Lampsilis teres) release sperm into the water column and it flows downstream for the females to filter. The sperm are drawn into the female as she filters water for food. Once the eggs of L. teres are fertilized, they sit within pouches of the modified gills and eventually develop into larvae termed glochidia. The mother of the glochodia needs to attach them to a host fish as soon as possible. These larvae are parasitic and they must find a suitable fish host in order to complete their life cycle. It is her job to make sure that the glochidia gets close enough to the fish in order to make a cyst on the fish. In order for this to occur, the mother uses her mantle to resemble fish food. After a fish goes for the bait, the yellow sandshell traps the host fish and the glochodia will become attached. Once the mother has successfully attached her offspring to the gills or fins of a host fish, they will remain there for 3 days to 10 months depending on the water temperature. After the glochidia have gone through metamorphosis, they will come out of the cyst as a small freshwater mussel. The little freshwater mussel will then fall to the bottom of the stream or lake and grow into a mature freshwater mussel. (O'Brien and Tignor, 2014; "Freshwater Mussels of the Upper Mississippi River System", 2006)
The mating system of freshwater mussels such as yellow sandshells is relatively simple. In the summer, male mussels release sperm into the water column and it flows downstream for the females to siphon the sperm and fertilize the eggs. ("Freshwater Mussels of the Upper Mississippi River System", 2006)
Yellow sandshells spawn in the summer and females store the glochidia until the following spring when the larvae will be released. Once the eggs of L. teres are fertilized, they sit within pouches of the modified gills and eventually develop into larvae called glochidia. The glochodia are released the following spring, and are very small when they attach to a host, at an average length and height of of 191 and 258μm. (O'Brien and Tignor, 2014; Roe, 2010)
Females provide parental care, as they brood the eggs and glochidia in pouches in their gills for almost a year. The glochidia remain there until they must attach to a host fish. The female parent also helps with this, by using her mantle as a lure to attract a fish. When the fish comes close to investigate the lure, the female releases the glochidia, ensuring that they will have a host. Once the glochidia are released, they are independent and parental care stops. (O'Brien and Tignor, 2014; Roe, 2010)
The lifespan of freshwater mussels such as the yellow sandshell is variable; however many mussels live very long lives. For example, some species may live for only 10 years and others may live for as long as 100 years. ("Freshwater Mussels of the Upper Mississippi River System", 2006)
The yellow sandshell is usually found in mussel beds along with many different species of mussels. These mussels spend most of their lives buried in the bottom sediments of rivers and lakes. They do not move around much as they are sedentary, though they do have a muscular foot that comes out their mantle which allows them to move and migrate if need be. Lampsilis teres may be sedentary; however they do make seasonal migrations. These seasonal migrations are at the greatest potential during the glochidial stage on fish. Also, some passive movement downstream takes place during high flows. Although these mollusks may migrate, none of them migrate farther than 200 km.
When yellow sandshells are only glochidia, they are parasitic on fish, though their female parent must first attract the fish host. Female yellow sandshells use their mantles to look like a minnow or fish food. This "bait" attracts the attention of a host fish. When the host fish bites the mantle, L. teres clamps down on the fish and the glochodium becomes attached. This behavior sets the cycle for the next generation of yellow sandshells. ("Lampsilis teres - (Rafinesque, 1820)", 2013; Hove, 2014; "Species profile:Minnesota DNR", 2014; O'Brien and Tignor, 2014)
Yellow sandshells do have the capacity to move using their large muscular foot for locomotion, however once they reach adulthood, they are sedentary creatures and do not stray far from where they successfully settled. ("Freshwater Mussels of the Upper Mississippi River System", 2006)
There is little information available about the communication and perception of Lampsilis teres. Most freshwater mussels are able to orient themselves, as well as detect changes in water temperature, changes in light, and physical touch. ("Lampsilis teres - (Rafinesque, 1820)", 2013)
The yellow sandshell has a diet similar to other bivalves. They mostly consume algae and decaying organic matter. Mussels eat by filtering bacteria, protozoans, algae, and other organic matter out of the water. Yellow sandshells draw water into their body through their incurrent siphon, remove food and oxygen with their gills, and then expel the filtered water through their excurrent siphon. Food particles are carried to the mussel's mouth by tiny hairlike cilia located on the gills. Waste is expelled through the excurrent siphon. Glochidia are parasitic and gain nutrients from the fish species that are acting as their hosts. ("Lampsilis teres - (Rafinesque, 1820)", 2013; "Species profile:Minnesota DNR", 2014)
Lampsilis teres is prey to a variety of mammals, waterfowl, and fish. Its only defense from predators is its hard shell, and the ability to burrow in the sediment to hide. ("Lampsilis teres - (Rafinesque, 1820)", 2013; "Species profile:Minnesota DNR", 2014)
Yellow sandshells are very important for the ecosystems in which they reside because they filter particles out of the water. They act as "nature's vacuum cleaners", and do a great job in cleansing the waters. They are also an excellent indicator of water quality. They are an important food source for other species that live in the aquatic environment. There are a number of fish that act as hosts for these mussels when they are in the larvae stage. The yellow sandshell acts as a parasitic organism as it is taking nutrients from whichever fish is acting as the host. Although they are parasitic as larvae, they do not seem to harm the fish at all. ("Yellow Sandshell", 2014; Roe, 2010)
One way that people benefit from the yellow sandshell is through the pearls that they contain. Pearls are of monetary value, and many people have exploited these organisms in order to make money from their pearls. Also, the shells that protect these organisms are economically important for humans as they are used for the button industry. These mussels have undergone significant pressure due to the wants of humans. The shells that protect the yellow sandshell are also used by humans for inlay work.
Other than being economically important, yellow sandshells also act as great indicators of water quality. This is important, because humans use these organisms in order to determine the quality of a stream, river, or a lake. They are great indicators of water quality because they live long and they are relatively immobile. They accumulate contaminants in the water which may be analyzed further by humans. ("Yellow Sandshell", 2014)
There are no known adverse affects of Lampsilis teres on humans.
Federally, the yellow sandshell (Lampsilis teres) is classified as Least Concern (LC) and P5 on the IUCN Red list. However, they are listed as endangered in several Midwestern states. These Midwestern states include Minnesota, Iowa, Wisconsin and Ohio. They have also been classified as regionally extinct in some states such as Oklahoma, South Dakota, Tennessee, Texas and West Virginia. There have been various studies conducted in many states in order to provide conservation efforts for the yellow sandshell, particularly in Minnesota. A ten year study was conducted in 1999 in order to get a better understanding of the yellow sandshell. Also, there have been efforts underway to propagate juvenile yellow sandshells for restocking into areas where habitat conditions have improved. (Hove, 2014; "Species profile:Minnesota DNR", 2014; Roe, 2010; "Lampsilis teres (Rafinesque, 1820) Yellow Sandshell", 2014)
Matt Steele (author), Minnesota State University Mankato, Robert Sorensen (editor), Minnesota State University, Mankato, Angela Miner (editor), Animal Diversity Web Staff.
living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.
Referring to an animal that lives on or near the bottom of a body of water. Also an aquatic biome consisting of the ocean bottom below the pelagic and coastal zones. Bottom habitats in the very deepest oceans (below 9000 m) are sometimes referred to as the abyssal zone. see also oceanic vent.
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
an animal that mainly eats decomposed plants and/or animals
particles of organic material from dead and decomposing organisms. Detritus is the result of the activity of decomposers (organisms that decompose organic material).
animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature
union of egg and spermatozoan
a method of feeding where small food particles are filtered from the surrounding water by various mechanisms. Used mainly by aquatic invertebrates, especially plankton, but also by baleen whales.
mainly lives in water that is not salty.
An animal that eats mainly plants or parts of plants.
having a body temperature that fluctuates with that of the immediate environment; having no mechanism or a poorly developed mechanism for regulating internal body temperature.
fertilization takes place within the female's body
A large change in the shape or structure of an animal that happens as the animal grows. In insects, "incomplete metamorphosis" is when young animals are similar to adults and change gradually into the adult form, and "complete metamorphosis" is when there is a profound change between larval and adult forms. Butterflies have complete metamorphosis, grasshoppers have incomplete metamorphosis.
makes seasonal movements between breeding and wintering grounds
having the capacity to move from one place to another.
the area in which the animal is naturally found, the region in which it is endemic.
an organism that obtains nutrients from other organisms in a harmful way that doesn't cause immediate death
photosynthetic or plant constituent of plankton; mainly unicellular algae. (Compare to zooplankton.)
breeding is confined to a particular season
remains in the same area
reproduction that includes combining the genetic contribution of two individuals, a male and a female
uses touch to communicate
that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).
uses sight to communicate
animal constituent of plankton; mainly small crustaceans and fish larvae. (Compare to phytoplankton.)
U.S. Fish and Wildlife Service. 2006. "Freshwater Mussels of the Upper Mississippi River System" (On-line). Life History. Accessed April 22, 2014 at http://www.fws.gov/midwest/mussel/life_history.html.
2013. "Lampsilis teres - (Rafinesque, 1820)" (On-line). NatureServe Explorer. Accessed April 23, 2014 at http://explorer.natureserve.org/servlet/NatureServe?searchName=Lampsilis+teres.
University of Illinois Board of Trustees. 2014. "Lampsilis teres (Rafinesque, 1820) Yellow Sandshell" (On-line). Illinois Natural History Survey Prairie Research Institute. Accessed April 21, 2014 at http://wwx.inhs.illinois.edu/collections/mollusk/publications/guide/index/148.
Geological Survey of Alabama. Results of Analysis of The Freshwater Mussel Fauna in The Alabama River Downstream of Claiborne and Millers Ferry Locks and Dams, 2006-07. OPEN-FILE REPORT 0708. Tuscaloosa, Alabama: Geological Survey of Alabama. 2007. Accessed March 25, 2014 at http://www.gsa.state.al.us/gsa/eco/pdf/ofr_0708.pdf.
MN DNR. 2014. "Species profile:Minnesota DNR" (On-line). Lampsilis teres Yellow Sandshell. Accessed April 21, 2014 at http://www.dnr.state.mn.us/rsg/profile.html?action=elementDetail&selectedElement=IMBIV21240.
Conservation Commission of Missouri. 2014. "Yellow Sandshell" (On-line). mdconline Missouri Department of Conservation. Accessed April 14, 2014 at http://mdc.mo.gov/discover-nature/field-guide/yellow-sandshell.
Cummings, K., J. Cordeiro. 2013. "Lampsilis teres" (On-line). The IUCN Red List of Threatened Species. Accessed April 21, 2014 at http://www.iucnredlist.org/details/188908/0-.
Hove, M. 2014. "Encyclopedia of Life" (On-line). Yellow sandshell-Morphology. Accessed April 07, 2014 at http://eol.org/pages/449587/details.
Johnson, P., K. Lellis, W. Michener, M. Freeman, C. Pringle. 2001. "Mussels (Family: Unionidae) of the Lower Flint River Basin with 1999 Stream Habitat and Mussel Community Survey Methods" (On-line). Accessed April 04, 2014 at http://www.jonesctr.org/education_and_outreach/educator_resources/mussel_manual.pdf.
O'Brien, C., B. Tignor. 2014. "Attracting a host fish is hard work" (On-line). Accessed April 22, 2014 at http://www.uvm.edu/~pass/tignor/mussels/attract.htm.
Roe, K. 2010. "Conservation Assessment The Yellow Sandshell, Lampsilis teres (Rafinesque, 1820)" (On-line). Accessed April 08, 2014 at http://www.fs.usda.gov/Internet/FSE_DOCUMENTS/fsm91_054368.pdf.