Gammarus acherondytes
Encyclopedia
Gammarus acherondytes is a species of crustacean
in family Gammaridae
. It is endemic to the Illinois Sinkhole Plain of Monroe
and St. Clair
counties in southwestern Illinois, including Illinois Caverns State Natural Area
. Historically it was known from six caves, but in a survey in 1995 the species was found at only three of the sites, with one further site inaccessible. This species occurs only in underground streams. It was first collected in 1938 and described as a new species in 1940. It has only been found in six cave streams, all lie within a 10-mile radius circle around Waterloo, Illinois
, making this a very localized species. However, there is no evidence that these cave streams are currently interconnected. The main threat to the species is groundwater contamination.
Crustacean
Crustaceans form a very large group of arthropods, usually treated as a subphylum, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 described species range in size from Stygotantulus stocki at , to the Japanese spider crab with a leg span...
in family Gammaridae
Gammaridae
Gammaridae is a family of amphipods. In North America they are included among the folk taxonomic category of "scuds", and otherwise gammarids is usually used as a common name....
. It is endemic to the Illinois Sinkhole Plain of Monroe
Monroe County, Illinois
Monroe County is a county located in the U.S. state of Illinois. According to the 2010 census, it has a population of 32,957, which is an increase of 19.3% from 27,619 in 2000. Its county seat is Waterloo...
and St. Clair
St. Clair County, Illinois
St. Clair County is a county located in the U.S. state of Illinois. In 1970, the U.S. Census Bureau placed the mean center of U.S. population in St. Clair County. According to the 2010 census, it has a population of 270,056, which is an increase of 5.5% from 256,082 in 2000. Its county seat is...
counties in southwestern Illinois, including Illinois Caverns State Natural Area
Illinois Caverns State Natural Area
Illinois Caverns is a state natural area in the New Design Precinct of Monroe County, Illinois. It features Illinois Caverns which is alternatively known as Mammoth Cave of Illinois . Illinois Caverns is the second-largest cave in Illinois and has more than 9.6 km of passages...
. Historically it was known from six caves, but in a survey in 1995 the species was found at only three of the sites, with one further site inaccessible. This species occurs only in underground streams. It was first collected in 1938 and described as a new species in 1940. It has only been found in six cave streams, all lie within a 10-mile radius circle around Waterloo, Illinois
Waterloo, Illinois
Waterloo is a city in Monroe County, Illinois, United States. The population was 7,614 at the 2000 census. It is the county seat of Monroe County.-Geography:Waterloo is located at ....
, making this a very localized species. However, there is no evidence that these cave streams are currently interconnected. The main threat to the species is groundwater contamination.
Source
- Crandall, K. 2002. Gammarus acherondytes. 2006 IUCN Red List of Threatened Species. Downloaded on 9 August 2007.