''Chirostoma attenuatum'' – also known as slender silverside – was featured in the 2009

IUCN Red List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biol ...

of Threatened Species and the

American Fisheries Society The American Fisheries Society (established 1870 in New York City), is the "world’s oldest and largest organization dedicated to strengthening the fisheries profession, advancing fisheries science, and conserving fisheries resources." It is a mem ...

. They are found in Patzcuaro, Central

Mexico Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...

. The

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

is at risk of being extinct. Eight helminth species, type of parasitic worms, including Posthodiplostomum minimum, Allocreadium mexicanum, Bothriocephalus acheilognathi, a cyclophyllidean cysticercoid, Arhythmorhynchus brevis, Spinitectus carolini, Capilaria patrcuarensis, and Eustrongylides sp., were discovered in 195 Chirostoma attenuatum fish from Lake Patzcuaro from October 1989 to December 1990. Posthodiplostomum minimum had the highest frequency and intensity; it had the most impact in harming the Chirostoma attenuatum fish.

References

attenuatum {{Atheriniformes-stub